DE10354396A1 - Production of di-, oligo- and polymers of dicarbonyl compounds as aqueous formulation or powder, used for tanning and as preservative, involves acid-catalyzed condensation of 2-substituted heterocyclic compound in water - Google Patents

Abstract

Production of aqueous formulations comprises heating 2-organyl-oxy-, -thio- or -amino-dihydrofuran, dihydropyran, tetrahydrooxepin and tetrahydrooxocin compound(s) in the presence of water and an acid catalyst and (partly) removing the hydroxy, thio or amine compound during or at the end of heating. Production of aqueous formulations comprises heating 2-organyl-oxy-, -thio- or -amino-dihydrofuran, dihydropyran, tetrahydrooxepin and tetrahydrooxocin compound(s) of formula (I) in the presence of water and an acid catalyst and (partly) removing H-X-R 3> during or at the end of heating. [Image] X : O, S or N-R 6>; R 3>, R 6>R, formyl or CO-R or may be combined to a ring if X is N-R 6>' R : 1-12 C alkyl or an optionally substituted 3-23 C cycloalkyl, 7-13 C aralkyl or 6-14 C aryl group; R 1>, R 2>, R 4>H or R or 2 adjacent groups may be combined to a ring; n : 1-4; and R 5>H or R or R 4> and R 5> or 2 adjacent R 5> groups may be combined to a ring. Independent claims are also included for the following: (A) aqueous formulations prepared by this process; and (B) mixtures of dimers, oligomers and polymers of dicarbonyl compound(s) of formula (III). [Image].

Description

in Gegenwart von Wasser und von einem sauren Katalysator erhitzt und während des oder im Anschluss an das Erhitzen H-X-R³ zumindest partiell abtrennt, wobei in Formel I die Variablen wie folgt definiert sind:
X ausgewählt aus Sauerstoff, Schwefel und N-R⁶,
R³, R⁶ gleich oder verschieden und ausgewählt aus C₁-C₁₂-Alkyl, C₃-C₁₂-Cycloalkyl, substituiert oder unsubstituiert, C₇-C₁₃-Aralkyl, C₆-C₁₄-Aryl, substituiert oder unsubstituiert, Formyl, CO-C₁-C₁₂-Alkyl, CO-C₃-C₁₂-Cycloalkyl, substituiert oder unsubstituiert, CO-C₇-C₁₃-Aralkyl, CO-C₆-C₁₄-Aryl, wobei für den Fall, dass X für N-R⁶ steht, R³ und R⁶ unter Bildung eines Rings miteinander verbunden sein können;
R¹, R², R⁴ gleich oder verschieden und ausgewählt aus Wasserstoff, C₁-C₁₂-Alkyl, C₃-C₁₂-Cycloalkyl, substituiert oder unsubstituiert, C₇-C₁₃-Aralkyl, C₆-C₁₄-Aryl, substituiert oder unsubstituiert, wobei jeweils zwei benachbarte Reste unter Bildung eines Rings miteinander verbunden sein können;
n eine ganze Zahl im Bereich von 1 bis 4;
R⁵ gleich oder verschieden und ausgewählt aus Wasserstoff, C₁-C₁₂-Alkyl, C₃-C₁₂-Cycloalkyl, substituiert oder unsubstituiert, C₇-C₁₃-Aralkyl, C₆-C₁₄-Aryl, substituiert oder unsubstituiert, wobei R⁵ mit R⁴ oder auch jeweils zwei benachbarte Reste R⁵ miteinander unter Bildung eines Rings verbunden sein können.The present invention relates to a process for the preparation of aqueous formulations, characterized in that at least one cyclic compound of the general formula I

heated in the presence of water and of an acidic catalyst and at least partially separated during or after the heating HXR ³ , wherein in the formula I, the variables are defined as follows:
X is selected from oxygen, sulfur and NR ⁶ ,
R ³ , R ^{6 are the} same or different and selected from C ₁ -C ₁₂ alkyl, C ₃ -C ₁₂ cycloalkyl, substituted or unsubstituted, C ₇ -C ₁₃ aralkyl, C ₆ -C ₁₄ aryl, substituted or unsubstituted , Formyl, CO-C ₁ -C ₁₂ -alkyl, CO-C ₃ -C ₁₂ -cycloalkyl, substituted or unsubstituted, CO-C ₇ -C ₁₃ -aralkyl, CO-C ₆ -C ₁₄ -aryl, wherein for the Case that X is NR ⁶ , R ³ and R ⁶ may be linked together to form a ring;
R ¹ , R ² , R ^{4 are} identical or different and selected from hydrogen, C ₁ -C ₁₂ -alkyl, C ₃ -C ₁₂ -cycloalkyl, substituted or unsubstituted, C ₇ -C ₁₃ -aralkyl, C ₆ -C ₁₄ - Aryl, substituted or unsubstituted, wherein each two adjacent radicals may be connected together to form a ring;
n is an integer in the range of 1 to 4;
R ^{5 is} identical or different and selected from hydrogen, C ₁ -C ₁₂ -alkyl, C ₃ -C ₁₂ -cycloalkyl, substituted or unsubstituted, C ₇ -C ₁₃ -aralkyl, C ₆ -C ₁₄ -aryl, substituted or unsubstituted, wherein R ⁵ with R ⁴ or also two adjacent radicals R ⁵ may be connected to each other to form a ring.

The The present invention further relates to aqueous formulations prepared according to the method of the invention, as well as the use of the aqueous formulations according to the invention for the preparation semi-finished or leather and powdered formulations containing in turn for the production of leather and as a preservative can be used. After all relates to the present invention leather and semi-finished products produced according to the invention.

For over 100 years For many years, chrome tanning in leather production is an important one chemical treatment, see for example Ullmann's Encyclopedia of Industrial Chemistry, Volume A15, pages 259 to 282 and in particular Page 268 ff., 5th edition, (1990), Verlag Chemie Weinheim. From ecological establish However, it is looking for alternatives to chrome tanning.

Known Further, there are methods in which the chromium is wholly or partially was replaced by organic tanning agents. Called the use the so-called syntans, which are sulfonated condensation products formaldehyde and phenol or sulfonated naphthalene-formaldehyde condensation products. Also mentioned is the use of so-called vegetable tanning agents. However, both classes of tanning agents provide for an increased COD value of the effluents and are for environmental reasons also not safe. In addition, it has been proven that the light fastness of the leather when using sulfonated phenol / formaldehyde condensation products often leaves something to be desired (Ullmann's Encyclopedia of Industrial Chemistry, Volume A15, pages 259-282 and in particular Page 270 ff., 5th edition, (1990), Verlag Chemie Weinheim).

Farther is tanning using aldehydes, especially dialdehydes such as glutaric dialdehyde, see, for example H. Herfeld, Library of the Leather, Volume III, page 191, Umschau Publisher Frankfurt / Main, 1984. The disadvantage, however, is that at low Amounts of glutaric dialdehyde, for example, 0.5 to 0.9 wt .-% based on the pelt weight), the shrinkage temperatures do not exceed 70 ° C and that Therefore, the semifinished products produced can only be insufficiently dewatered. During the Falzens occurs a glue on the meat side of the leather and influences the quality of the leather disadvantageous.

glutaraldehyde is often referred to in the literature as glutaraldehyde, In the following, both expressions become equivalent uses.

With larger amounts of glutaric dialdehyde used, occupational safety problems can arise of the toxic properties of glutaric dialdehyde. In addition, it is observed that leather is generally obtained in leathery tones and that subsequent variable processing, as many tanneries desire, is no longer possible.

It is known, glutaraldehyde in partially or completely acetalized Use form for tanning, for example as methyl acetal (Ullmann's Encyclopedia of Industrial Chemistry, Volume A15, pages 259-282 and in particular Page 273 ff., 5th edition, (1990), Verlag Chemie Weinheim). The However, tanned semifinished products tend to generally quickly to yellowing.

In DE-C 38 11 267 discloses that acetalization of glutaric dialdehyde or other dialdehydes having 2 to 8 C atoms, with short chain Alkyl glycols, alkyl polyglycols, aliphatic alcohols, glycerol or saccharides brings beneficial effects. However, the vapor pressure is dialdehydes, which are easily obtained from very hydrolysis-sensitive acetals degenerated be, still noticeable. Also, the application technology can be Properties of the leather thus obtained further improve.

Out EP-A 0 066 224 is a process for the preparation of a precursor known by glutaric dialdehyde. By heating 2-alkoxy-3,4-dihydropyrans with acid and water becomes a mixture of 2-hydroxy-6-alkoxytetrahydropyran, Obtained 2,6-dialkoxytetrahydropyran and glutaric dialdehyde, wherein the amount of unwanted resulting oligomeric and polymeric by-products only small is (page 2, line 33 ff.). In the presence of water put the described tetrahydropyran derivatives glutaraldehyde free.

Out US 2,546,018 a process for the preparation of glutaraldehyde and C-substituted glutaraldehydes is known, which is characterized by hydrolysis of glutaraldehyde in an aqueous, optionally aqueous acidic medium. The by the in US 2,546,018 The disclosed processes obtainable glutaraldehyde and C-substituted dialdehydes are purified by fractional distillation.

For the according to EP-A 0 066 224, DE-A 44 44 709 and US 2,546,018 available glutaraldehyde or its derivatives are the same gerbereite disadvantages as listed above.

It It was therefore the object to provide a method by the versatile watery Formulations can be provided. Furthermore, the Task, watery To provide formulations that are versatile reagents for the production of semi-finished products and leather are suitable and avoid the disadvantages known from the prior art. Farther the task was watery To provide formulations suitable as preservatives are. After all The task was to prepare uses for aqueous formulations to deliver.

in denen die Variablen wie folgt definiert sind.
X ist ausgewählt aus Sauerstoff, Schwefel oder N-R⁶, wobei Sauerstoff bevorzugt ist.
R³ und R⁶ sind gleich oder verschieden und ausgewählt aus
C₁-C₁₂-Alkyl, wie Methyl, Ethyl, n-Propyl, iso-Propyl, n-Butyl, iso-Butyl, sec.-Butyl, tert.-Butyl, n-Pentyl, iso-Pentyl, sec.-Pentyl, neo-Pentyl, 1,2-Dimethylpropyl, iso-Amyl, n-Hexyl, iso-Hexyl, sec.-Hexyl, n-Heptyl, iso-Heptyl, n-Octyl, n-Nonyl, n-Decyl, und n-Dodecyl; bevorzugt C₁-C₆-Alkyl wie Methyl, Ethyl, n-Propyl, iso-Propyl, n-Butyl, iso-Butyl, sec.-Butyl, tert.-Butyl, n-Pentyl, iso-Pentyl, sec.-Pentyl, neo-Pentyl, 1,2-Dimethylpropyl, iso-Amyl, n-Hexyl, iso-Hexyl, sec.-Hexyl, besonders bevorzugt C₁-C₄-Alkyl wie Methyl, Ethyl, n-Propyl, iso-Propyl, n-Butyl, iso-Butyl, sec.-Butyl und tert.-Butyl, ganz besonders bevorzugt Methyl;
C₃-C₁₂-Cycloalkyl wie Cyclopropyl, Cyclobutyl, Cyclopentyl, Cyclohexyl, Cycloheptyl, Cyclooctyl, Cyclononyl, Cyclodecyl, Cycloundecyl und Cyclododecyl; bevorzugt sind Cyclopentyl, Cyclohexyl und Cycloheptyl;
unter substituierten Cycloalkylgruppen seien beispielhaft genannt: 2-Methylcyclopentyl, 3-Methylcyclopentyl, cis-2,4-Dimethylcyclopentyl, trans-2,4-Dimethylcyclopentyl 2,2,4,4-Tetramethylcyclopentyl, 2-Methylcyclohexyl, 3-Methylcyclohexyl, 4-Methylcyclohexyl, cis-2,5-Dimethylcyclohexyl, trans-2,5-Dimethylcyclohexyl, 2,2,5,5-Tetramethylcyclohexyl, 2-Methoxycyclopentyl, 2-Methoxycyclohexyl, 3-Methoxycyclopentyl, 3-Methoxycyclohexyl, 2-Chlorcyclopentyl, 3-Chlorcyclopentyl, 2,4-Dichlorcyclopentyl, 2,2,4,4-Tetrachlorcyclopentyl, 2-Chlorcyclohexyl, 3-Chlorcyclohexyl, 4-Chlorcyclohexyl, 2,5-Dichlorcyclohexyl, 2,2,5,5-Tetrachlorcyclohexyl, 2-Thiomethylcyclopentyl, 2-Thiomethylcyclohexyl, 3-Thiomethyl-cyclopentyl, 3-Thiomethylcyclohexyl;
C₇-C₁₃-Aralkyl, bevorzugt C₇- bis C₁₂-Phenylalkyl wie Benzyl, 1-Phenethyl, 2-Phenethyl, 1-Phenyl-propyl, 2-Phenyl-propyl, 3-Phenyl-propyl, Neophyl (1-Methyl-1-phenylethyl), 1-Phenyl-butyl, 2-Phenyl-butyl, 3-Phenyl-butyl und 4-Phenyl-butyl, besonders bevorzugt Benzyl,
C₆-C₁₄-Aryl, beispielsweise Phenyl, 1-Naphthyl, 2-Naphthyl, 1-Anthryl, 2-Anthryl, 9-Anthryl, 1-Phenanthryl, 2-Phenanthryl, 3-Phenanthryl, 4-Phenanthryl und 9-Phenanthryl, bevorzugt Phenyl, 1-Naphthyl und 2-Naphthyl, besonders bevorzugt Phenyl, unsubstituiert
oder substituiertes C₆-C₁₄-Aryl, beispielsweise Phenyl, 1-Naphthyl, 2-Naphthyl, 1-Anthryl, 2-Anthryl, 9-Anthryl, 1-Phenanthryl, 2-Phenanthryl, 3-Phenanthryl, 4- Phenanthryl und 9-Phenanthryl, bevorzugt Phenyl, 1-Naphthyl und 2-Naphthyl, besonders bevorzugt Phenyl, substituiert durch eine oder mehrere

• – C₁-C₁₂-Alkylgruppen, wie Methyl, Ethyl, n-Propyl, iso-Propyl, n-Butyl, iso-Butyl, sec.-Butyl, tert.-Butyl, n-Pentyl, iso-Pentyl, sec.-Pentyl, neo-Pentyl, 1,2-Dimethylpropyl, iso-Amyl, n-Hexyl, iso-Hexyl, sec.-Hexyl, n-Heptyl, iso-Heptyl, n-Octyl, n-Nonyl, n-Decyl, und n-Dodecyl; bevorzugt C₁-C₆-Alkyl wie Methyl, Ethyl, n-Propyl, iso-Propyl, n-Butyl, iso-Butyl, sec.-Butyl, tert.-Butyl, n-Pentyl, iso-Pentyl, sec.-Pentyl, neo-Pentyl, 1,2-Dimethylpropyl, iso-Amyl, n-Hexyl, iso-Hexyl, sec.-Hexyl, besonders bevorzugt C₁-C₄-Alkyl wie Methyl, Ethyl, n-Propyl, iso-Propyl, n-Butyl, iso-Butyl, sec.-Butyl und tert.-Butyl;
• – Halogene wie Fluor, Chlor, Brom und Jod, wobei Chlor und Brom bevorzugt sind,
• – C₁-C₁₂-Alkoxygruppen, bevorzugt C₁-C₆-Alkoxygruppen wie Methoxy, Ethoxy, n-Propoxy, iso-Propoxy, n-Butoxy, iso-Butoxy, sec.-Butoxy, tert.-Butoxy, n-Pentoxy, iso-Pentoxy, n-Hexoxy und iso-Hexoxy, besonders bevorzugt Methoxy, Ethoxy, n-Propoxy und n-Butoxy;

Formyl,
CO-C₁-C₁₂-Alkyl wie Acetyl, Propionyl, n-Butyryl, iso-Butyryl, sec.-Butyryl, tert.-Butyryl, n-Valeroyl, iso-Valeroyl, sec.-Valeroyl, n-Capryl, n-Dodecanoyl; bevorzugt CO-C₁-C₄-Alkyl wie Acetyl, Propionyl, n-Butyryl, iso-Butyryl, sec.-Butyryl, tert.-Butyryl, ganz besonders bevorzugt Acetyl;
CO-C₃-C₁₂-Cycloalkyl wie Cyclopropylcarbonyl, Cyclobutylcarbonyl, Cyclopentylcarbonyl, Cyclohexylcarbonyl, Cycloheptylcarbonyl, Cyclooctylcarbonyl, Cyclononylcarbonyl, Cyclodecylcarbonyl, Cycloundecylcarbonyl und Cyclododecylcarbonyl; bevorzugt sind Cyclopentylcarbonyl, Cyclohexylcarbonyl und Cycloheptylcarbonyl;
unter substituierten Cycloalkylgruppen seien beispielhaft genannt: 2-Methylcyclopentylcarbonyl, 3-Methylcyclopentylcarbonyl, 2-Methylcyclohexylcarbonyl, 3-Methylcyclohexylcarbonyl, 4-Methylcyclo-hexylcarbonyl, cis-2,5-Dimethylcyclohexylcarbonyl, trans-2,5-Dimethyl-cyclohexylcarbonyl, 2-Methoxycyclopentylcarbonyl, 2-Methoxycyclo-hexylcarbonyl, 3-Methoxycyclopentylcarbonyl, 3-Methoxycyclohexyl-carbonyl, 2-Chlorcyclopentylcarbonyl, 3-Chlorcyclopentylcarbonyl, 2,4-Dichlorcyclopentylcarbonyl, 2-Chlorcyclohexylcarbonyl, 3-Chlorcyclo-hexylcarbonyl, 4-Chlorcyclohexylcarbonyl, 2,5-Dichlor cyclohexylcarbonyl, 2-Thiomethylcyclopentylcarbonyl, 2-Thiomethylcyclohexylcarbonyl, 3-Thiomethyl-cyclopentylcarbonyl, 3-Thiomethylcyclohexyl;
CO-C₇-C₁₃-Aralkyl, bevorzugt CO-C₇-C₁₂-Phenylalkyl wie Phenylacetyl, ω-Phenylpropionyl, besonders bevorzugt Phenylacetyl,
CO-C₆-C₁₄-Aryl, beispielsweise Benzoyl, 1-Naphthoyl, 2-Naphthoyl, 1-Anthroyl, 2-Anthroyl, 9-Anthroyl, 1-Phenanthroyl, 2-Phenanthroyl, 3-Phenanthroyl, 4-Phenanthroyl und 9-Phenanthroyl, bevorzugt Benzoyl, 1-Naphthoyl und 2-Naphthoyl, besonders bevorzugt Benzoyl.
R¹, R², R⁴ gleich oder verschieden und ausgewählt aus Wasserstoff,
C₁-C₁₂-Alkyl, wie Methyl, Ethyl, n-Propyl, iso-Propyl, n-Butyl, iso-Butyl, sec.-Butyl, tert.-Butyl, n-Pentyl, iso-Pentyl, sec.-Pentyl, neo-Pentyl, 1,2-Dimethylpropyl, iso-Amyl, n-Hexyl, iso-Hexyl, sec.-Hexyl, n-Heptyl, iso-Heptyl, n-Octyl, n-Nonyl, n-Decyl, und n-Dodecyl; bevorzugt C₁-C₆-Alkyl wie Methyl, Ethyl, n-Propyl, iso-Propyl, n-Butyl, iso-Butyl, sec.-Butyl, tert.-Butyl, n-Pentyl, iso-Pentyl, sec.-Pentyl, neo-Pentyl, 1,2-Dimethylpropyl, iso-Amyl, n-Hexyl, iso-Hexyl, sec.-Hexyl, besonders bevorzugt C₁-C₄-Alkyl wie Methyl, Ethyl, n-Propyl, iso-Propyl, n-Butyl, iso-Butyl, sec.-Butyl und tert.-Butyl, ganz besonders bevorzugt Methyl;
C₃-C₁₂-Cycloalkyl, substituiert oder unsubstituiert, wie Cyclopropyl, Cyclobutyl, Cyclopentyl, Cyclohexyl, Cycloheptyl, Cyclooctyl, Cyclononyl, Cyclodecyl, Cycloundecyl und Cyclododecyl; bevorzugt sind Cyclopentyl, Cyclohexyl und Cycloheptyl;
unter substituierten Cycloalkylgruppen seien beispielhaft genannt: 2-Methylcyclopentyl, 3-Methylcyclopentyl, cis-2,4-Dimethylcyclopentyl, trans-2,4-Dimethylcyclopentyl 2,2,4,4-Tetramethylcyclopentyl, 2-Methylcyclohexyl, 3-Methylcyclohexyl, 4-Methylcyclohexyl, cis-2,5-Dimethylcyclohexyl, trans-2,5-Dimethylcyclohexyl, 2,2,5,5-Tetramethylcyclohexyl, 2-Methoxycyclopentyl, 2-Methoxycyclohexyl, 3-Methoxycyclopentyl, 3-Methoxycyclohexyl, 2-Chlorcyclopentyl, 3-Chlorcyclopentyl, 2,4-Dichlorcyclopentyl, 2,2,4,4-Tetrachlorcyclopentyl, 2-Chlorcyclohexyl, 3-Chlorcyclohexyl, 4-Chlorcyclohexyl, 2,5-Dichlorcyclohexyl, 2,2,5,5-Tetrachlorcyclohexyl, 2-Thiomethylcyclopentyl, 2-Thiomethylcyclohexyl, 3-Thiomethyl-cyclopentyl, 3-Thiomethylcyclohexyl;
C₇-C₁₃-Aralkyl, bevorzugt C₇- bis C₁₂-Phenylalkyl wie Benzyl, 1-Phenethyl, 2-Phenethyl, 1-Phenyl-propyl, 2-Phenyl-propyl, 3-Phenyl-propyl, Neophyl (1-Methyl-l-phenylethyl), 1-Phenyl-butyl, 2-Phenyl-butyl, 3-Phenyl-butyl und 4-Phenyl-butyl, besonders bevorzugt Benzyl,
C₆-C₁₄-Aryl, beispielsweise Phenyl, 1-Naphthyl, 2-Naphthyl, 1-Anthryl, 2-Anthryl, 9-Anthryl, 1-Phenanthryl, 2-Phenanthryl, 3-Phenanthryl, 4-Phenanthryl und 9-Phenanthryl, bevorzugt Phenyl, 1-Naphthyl und 2-Naphthyl, besonders bevorzugt Phenyl,
unsubstituiert oder substituiertes
C₆-C₁₄-Aryl, beispielsweise Phenyl, 1-Naphthyl, 2-Naphthyl, 1-Anthryl, 2-Anthryl, 9-Anthryl, 1-Phenanthryl, 2-Phenanthryl, 3-Phenanthryl, 4-Phenanthryl und 9-Phenanthryl, bevorzugt Phenyl, 1-Naphthyl und 2-Naphthyl, besonders bevorzugt Phenyl, unsubstituiert oder substituiert durch eine oder mehrere

• – C₁-C₁₂-Alkylgruppen, wie Methyl, Ethyl, n-Propyl, iso-Propyl, n-Butyl, iso-Butyl, sec.-Butyl, tert.-Butyl, n-Pentyl, iso-Pentyl, sec.-Pentyl, neo-Pentyl, 1,2-Dimethylpropyl, iso-Amyl, n-Hexyl, iso-Hexyl, sec.-Hexyl, n-Heptyl, iso-Heptyl, n-Octyl, n-Nonyl, n-Decyl, und n-Dodecyl; bevorzugt C₁-C₆-Alkyl wie Methyl, Ethyl, n-Propyl, iso-Propyl, n-Butyl, iso-Butyl, sec.-Butyl, tert.-Butyl, n-Pentyl, iso-Pentyl, sec.-Pentyl, neo-Pentyl, 1,2-Dimethylpropyl, iso-Amyl, n-Hexyl, iso-Hexyl, sec.-Hexyl, besonders bevorzugt C₁-C₄-Alkyl wie Methyl, Ethyl, n-Propyl, iso-Propyl, n-Butyl, iso-Butyl, sec.-Butyl und tert.-Butyl;
• – Halogene wie Fluor, Chlor, Brom und Jod, wobei Chlor und Brom bevorzugt sind,
• – C₁-C₁₂-Alkoxygruppen, bevorzugt C₁-C₆-Alkoxygruppen wie Methoxy, Ethoxy, n-Propoxy, iso-Propoxy, n-Butoxy, iso-Butoxy, sec.-Butoxy, tert.-Butoxy, n-Pentoxy, iso-Pentoxy, n-Hexoxy und iso-Hexoxy, besonders bevorzugt Methoxy, Ethoxy, n-Propoxy und n-Butoxy;

wobei jeweils zwei benachbarte Reste unter Bildung eines Rings miteinander verbunden sein können. So können beispielsweise R¹ und R² beispielsweise gemeinsam C₁-C₈-Alkylen, unsubstituiert oder substituiert mit z.B. C₁-C₁₂-Alkyl oder C₆-C₁₄-Aryl, sein. Beispielhaft seien genannt: -CH₂-, -CH(CH₃)-, -(CH₂)₂-, -CH₂-CH(CH₃)-, -CH₂-CH(C₂H₅)-, -(CH₂)₃-, -(CN₂)₂-CH(CH₃)-, -(CH₂)₂-CH(C₂H₅)-, -(CH₂)₂-CH(C₆H₅)-, -(CH₂)₄-, -(CH₂)₅-, -(CH₂)₆-, -(CH₂)₇-, -CH(CH₃)-CH₂-CH₂-CH(CH₃)-, -CH(CH₃)-CH₂-CH₂-CH₂-CH(CH₃)-, vorzugsweise C₃-C₅-Alkylen wie beispielsweise -(CH₂)₃-, -(CH₂)₄-, -(CH₂)₅-.
n eine ganze Zahl im Bereich von 1 bis 4, insbesondere 2 oder 3;
R⁵ gleich oder verschieden und ausgewählt aus Wasserstoff,
C₁-C₁₂-Alkyl, wie Methyl, Ethyl, n-Propyl, iso-Propyl, n-Butyl, iso-Butyl, sec.-Butyl, tert.-Butyl, n-Pentyl, iso-Pentyl, sec.-Pentyl, neo-Pentyl, 1,2-Dimethylpropyl, iso-Amyl, n-Hexyl, iso-Hexyl, sec.-Hexyl, n-Heptyl, iso-Heptyl, n-Octyl, n-Nonyl, n-Decyl, und n-Dodecyl; bevorzugt C₁-C₆-Alkyl wie Methyl, Ethyl, n-Propyl, Iso-Propyl, n-Butyl, iso-Butyl, sec.-Butyl, tert.-Butyl, n-Pentyl, iso-Pentyl, sec.-Pentyl, neo-Pentyl, 1,2-Dimethylpropyl, iso-Amyl, n-Hexyl, iso-Hexyl, sec.-Hexyl, besonders bevorzugt C₁-C₄-Alkyl wie Methyl, Ethyl, n-Propyl, iso-Propyl, n-Butyl, iso-Butyl, sec.-Butyl und tert.-Butyl, ganz besonders bevorzugt Methyl;
C₃-C₁₂-Cycloalkyl, substituiert oder unsubstituiert, wie Cyclopropyl, Cyclobutyl, Cyclopentyl, Cyclohexyl, Cycloheptyl, Cyclooctyl, Cyclononyl, Cyclodecyl, Cycloundecyl und Cyclododecyl; bevorzugt sind Cyclopentyl, Cyclohexyl und Cycloheptyl; unter substituierten Cycloalkylgruppen seien beispielhaft genannt: 2-Methylcyclopentyl, 3-Methylcyclopentyl, cis-2,4-Dimethylcyclopentyl, trans-2,4-Dimethylcyclopentyl 2,2,4,4-Tetramethylcyclopentyl, 2-Methylcyclohexyl, 3-Methylcyclohexyl, 4-Methylcyclohexyl, cis-2,5-Dimethylcyclohexyl, trans-2,5-Dimethylcyclohexyl, 2,2,5,5-Tetramethylcyclohexyl, 2-Methoxycyclopentyl, 2-Methoxycyclohexyl, 3-Methoxycyclopentyl, 3-Methoxycyclohexyl, 2-Chlorcyclopentyl, 3-Chlorcyclopentyl, 2,4-Dichlorcyclopentyl, 2,2,4,4-Tetrachlorcyclopentyl, 2-Chlorcyclohexyl, 3-Chlorcyclohexyl, 4-Chlorcyclohexyl, 2,5-Dichlorcyclohexyl, 2,2,5,5-Tetrachlorcyclohexyl, 2-Thiomethylcyclopentyl, 2-Thiomethylcyclohexyl, 3-Thiomethyl-cyclopentyl, 3-Thiomethylcyclohexyl;
C₇-C₁₃-Aralkyl, bevorzugt C₇- bis C₁₂-Phenylalkyl wie Benzyl, 1-Phenethyl, 2-Phenethyl, 1-Phenyl-propyl, 2-Phenyl-propyl, 3-Phenyl-propyl, Neophyl (1-Methyl-1-phenylethyl), 1-Phenyl-butyl, 2-Phenyl-butyl, 3-Phenyl-butyl und 4-Phenyl-butyl, besonders bevorzugt Benzyl,
C₆-C₁₄-Aryl, substituiert oder unsubstituiert, wobei substituierte und unsubstituierte C₆-C₁₄-Arylreste wie oben stehend definiert sind.Accordingly, the method defined above was found. The inventive method is based on compounds of the general formula I.

where the variables are defined as follows.
X is selected from oxygen, sulfur or NR ⁶ , with oxygen being preferred.
R ³ and R ⁶ are the same or different and selected from
C ₁ -C ₁₂ -alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec. Pentyl, neo-pentyl, 1,2-dimethylpropyl, iso-amyl, n-hexyl, iso -hexyl, sec-hexyl, n-heptyl, iso-heptyl, n-octyl, n-nonyl, n-decyl, and n-dodecyl; preferably C ₁ -C ₆ -alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec. Pentyl, neo-pentyl, 1,2-dimethylpropyl, iso-amyl, n-hexyl, iso-hexyl, sec-hexyl, more preferably C ₁ -C ₄ alkyl such as methyl, ethyl, n-propyl, iso-propyl , n-butyl, iso-butyl, sec-butyl and tert-butyl, most preferably methyl;
C ₃ -C ₁₂ cycloalkyl such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl and cyclododecyl; preferred are cyclopentyl, cyclohexyl and cycloheptyl;
Examples of substituted cycloalkyl groups are: 2-methylcyclopentyl, 3-methylcyclopentyl, cis-2,4-dimethylcyclopentyl, trans-2,4-dimethylcyclopentyl 2,2,4,4-tetramethylcyclopentyl, 2-methylcyclohexyl, 3-methylcyclohexyl, 4- Methylcyclohexyl, cis-2,5-dimethylcyclohexyl, trans-2,5-dimethylcyclohexyl, 2,2,5,5-tetramethylcyclohexyl, 2-methoxycyclopentyl, 2-methoxycyclohexyl, 3-methoxycyclopentyl, 3-methoxycyclohexyl, 2-chlorocyclopentyl, 3-chlorocyclopentyl, 2,4-dichlorocyclopentyl, 2,2,4,4-tetrachlorocyclopentyl, 2-chlorocyclohexyl, 3-chlorocyclohexyl, 4-chlorocyclohexyl, 2,5-dichlorocyclohexyl, 2,2,5,5-tetrachlorocyclohexyl, 2-thiomethylcyclopentyl, 2-thiomethylcyclohexyl, 3-thiomethyl-cyclopentyl, 3-thiomethylcyclohexyl;
C ₇ -C ₁₃ aralkyl, preferably C ₇ - to C ₁₂ phenylalkyl such as benzyl, 1-phenethyl, 2-phenethyl, 1-phenyl-propyl, 2-phenyl-propyl, 3-phenyl-propyl, neophyl (1- Methyl-1-phenylethyl), 1-phenyl-butyl, 2-phenyl-butyl, 3-phenyl-butyl and 4-phenyl-butyl, more preferably benzyl,
C ₆ -C ₁₄ aryl, for example phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl and 9-phenanthryl , Preferably phenyl, 1-naphthyl and 2-naphthyl, more preferably phenyl, unsubstituted
or substituted C ₆ -C ₁₄ aryl, for example phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl and 9 Phenanthryl, preferably phenyl, 1-naphthyl and 2-naphthyl, most preferably phenyl substituted by one or more

• C ₁ -C ₁₂ -alkyl groups, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec. Pentyl, neo-pentyl, 1,2-dimethylpropyl, iso-amyl, n-hexyl, iso-hexyl, sec-hexyl, n-heptyl, iso-heptyl, n-octyl, n-nonyl, n-decyl, and n-dodecyl; preferably C ₁ -C ₆ -alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec. Pentyl, neo-pentyl, 1,2-dimethylpropyl, iso-amyl, n-hexyl, iso-hexyl, sec-hexyl, more preferably C ₁ -C ₄ alkyl such as methyl, ethyl, n-propyl, iso-propyl , n-butyl, iso-butyl, sec-butyl and tert-butyl;
• Halogens such as fluorine, chlorine, bromine and iodine, chlorine and bromine being preferred,
• C ₁ -C ₁₂ -alkoxy groups, preferably C ₁ -C ₆ -alkoxy groups, such as methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, n- Pentoxy, iso-pentoxy, n-hexoxy and iso-hexoxy, more preferably methoxy, ethoxy, n-propoxy and n-butoxy;

formyl,
CO-C ₁ -C ₁₂ -alkyl, such as acetyl, propionyl, n-butyryl, isobutyryl, sec-butyryl, tert-butyryl, n-valeroyl, iso-valeroyl, sec-valeroyl, n-capryl, n -Dodecanoyl; preferably CO-C ₁ -C ₄ -alkyl, such as acetyl, propionyl, n-butyryl, isobutyryl, sec-butyryl, tert-butyryl, very particularly preferably acetyl;
CO-C ₃ -C ₁₂ cycloalkyl such as cyclopropylcarbonyl, cyclobutylcarbonyl, cyclopentylcarbonyl, cyclohexylcarbonyl, cycloheptylcarbonyl, cyclooctylcarbonyl, cyclononylcarbonyl, cyclodecylcarbonyl, cycloundecylcarbonyl and cyclododecylcarbonyl; preferred are cyclopentylcarbonyl, cyclohexylcarbonyl and cycloheptylcarbonyl;
Examples of substituted cycloalkyl groups include 2-methylcyclopentylcarbonyl, 3-methylcyclopentylcarbonyl, 2-methylcyclohexylcarbonyl, 3-methylcyclohexylcarbonyl, 4-methylcyclohexylcarbonyl, cis-2,5-dimethylcyclohexylcarbonyl, trans-2,5-dimethylcyclohexylcarbonyl, 2-methoxycyclopentylcarbonyl , 2-methoxycyclohexylcarbonyl, 3-methoxycyclopentylcarbonyl, 3-methoxycyclohexylcarbonyl, 2-chlorocyclopentylcarbonyl, 3-chlorocyclopentylcarbonyl, 2,4-dichlorocyclopentylcarbonyl, 2-chlorocyclohexylcarbonyl, 3-chlorocyclohexylcarbonyl, 4-chlorocyclohexylcarbonyl, 2,5-dichloro cyclohexylcarbonyl, 2-thiomethylcyclopentylcarbonyl, 2-thiomethylcyclohexylcarbonyl, 3-thiomethylcyclopentylcarbonyl, 3-thiomethylcyclohexyl;
CO-C ₇ -C ₁₃ -aralkyl, preferably CO-C ₇ -C ₁₂ -phenylalkyl, such as phenylacetyl, ω-phenylpropionyl, particularly preferably phenylacetyl,
CO-C ₆ -C ₁₄ aryl, for example, benzoyl, 1-naphthoyl, 2-naphthoyl, 1-anthroyl, 2-anthroyl, 9-anthroyl, 1-phenanthroyl, 2-phenanthroyl, 3-phenanthroyl, 4-phenanthroyl and 9 Phenothroyl, preferably benzoyl, 1-naphthoyl and 2-naphthoyl, more preferably benzoyl.
R ¹ , R ² , R ^{4 are} identical or different and selected from hydrogen,
C ₁ -C ₁₂ -alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec. Pentyl, neo-pentyl, 1,2-dimethylpropyl, iso-amyl, n-hexyl, iso -hexyl, sec-hexyl, n-heptyl, iso-heptyl, n-octyl, n-nonyl, n-decyl, and n-dodecyl; preferably C ₁ -C ₆ -alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec. Pentyl, neo-pentyl, 1,2-dimethylpropyl, iso-amyl, n-hexyl, iso-hexyl, sec-hexyl, more preferably C ₁ -C ₄ alkyl such as methyl, ethyl, n-propyl, iso-propyl , n-butyl, iso-butyl, sec-butyl and tert-butyl, most preferably methyl;
C ₃ -C ₁₂ cycloalkyl, substituted or unsubstituted, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl and cyclododecyl; preferred are cyclopentyl, cyclohexyl and cycloheptyl;
Examples of substituted cycloalkyl groups are: 2-methylcyclopentyl, 3-methylcyclopentyl, cis-2,4-dimethylcyclopentyl, trans-2,4-dimethylcyclopentyl 2,2,4,4-tetramethylcyclopentyl, 2-methylcyclohexyl, 3-methylcyclohexyl, 4- Methylcyclohexyl, cis-2,5-dimethylcyclohexyl, trans-2,5-dimethylcyclohexyl, 2,2,5,5-tetramethylcyclohexyl, 2-methoxycyclopentyl, 2-methoxycyclohexyl, 3-methoxycyclopentyl, 3-methoxycyclohexyl, 2-chlorocyclopentyl, 3 Chlorocyclopentyl, 2,4-dichlorocyclopentyl, 2,2,4,4-tetrachlorocyclopentyl, 2-chlorocyclohexyl, 3-chlorocyclohexyl, 4-chlorocyclohexyl, 2,5-dichlorocyclohexyl, 2,2,5,5-tetrachlorocyclohexyl, 2-thiomethylcyclopentyl, 2-thiomethylcyclohexyl, 3-thiomethyl-cyclopentyl, 3-thiomethylcyclohexyl;
C ₇ -C ₁₃ aralkyl, preferably C ₇ - to C ₁₂ phenylalkyl such as benzyl, 1-phenethyl, 2-phenethyl, 1-phenyl-propyl, 2-phenyl-propyl, 3-phenyl-propyl, neophyl (1- Methyl-1-phenylethyl), 1-phenyl-butyl, 2-phenyl-butyl, 3-phenyl-butyl and 4-phenyl-butyl, more preferably benzyl,
C ₆ -C ₁₄ aryl, for example phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl and 9-phenanthryl , preferably phenyl, 1-naphthyl and 2-naphthyl, more preferably phenyl,
unsubstituted or substituted
C ₆ -C ₁₄ aryl, for example phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl and 9-phenanthryl Preferably, phenyl, 1-naphthyl and 2-naphthyl, more preferably phenyl, unsubstituted or substituted by one or more

• C ₁ -C ₁₂ -alkyl groups, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec. Pentyl, neo-pentyl, 1,2-dimethylpropyl, iso-amyl, n-hexyl, iso-hexyl, sec-hexyl, n-heptyl, iso-heptyl, n-octyl, n-nonyl, n-decyl, and n-dodecyl; preferably C ₁ -C ₆ -alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec. Pentyl, neo-pentyl, 1,2-dimethylpropyl, iso-amyl, n-hexyl, iso-hexyl, sec-hexyl, more preferably C ₁ -C ₄ alkyl such as methyl, ethyl, n-propyl, iso-propyl , n-butyl, iso-butyl, sec-butyl and tert-butyl;
• Halogens such as fluorine, chlorine, bromine and iodine, chlorine and bromine being preferred,
• C ₁ -C ₁₂ -alkoxy groups, preferably C ₁ -C ₆ -alkoxy groups, such as methoxy, ethoxy, n-propoxy, isopropoxy, n-butoxy, isobutoxy, sec-butoxy, tert-butoxy, n- Pentoxy, iso-pentoxy, n-hexoxy and iso-hexoxy, more preferably methoxy, ethoxy, n-propoxy and n-butoxy;

wherein each two adjacent radicals may be connected together to form a ring. Thus, for example, R ¹ and R ² may be, for example, together C ₁ -C ₈ -alkylene, unsubstituted or substituted by, for example, C ₁ -C ₁₂ -alkyl or C ₆ -C ₁₄ -aryl. Examples include: -CH ₂ -, -CH (CH ₃ ) -, - (CH ₂ ) ₂ -, -CH ₂ -CH (CH ₃ ) -, -CH ₂ -CH (C ₂ H ₅ ) -, - (CH ₂ ) ₃ -, - (CN ₂ ) ₂ -CH (CH ₃ ) -, - (CH ₂ ) ₂ -CH (C ₂ H ₅ ) -, - (CH ₂ ) ₂ -CH (C ₆ H ₅ ) -, - (CH ₂ ) ₄ -, - (CH ₂ ) ₅ -, - (CH ₂ ) ₆ -, - (CH ₂ ) ₇ -, -CH (CH ₃ ) -CH ₂ -CH ₂ -CH ( CH ₃ ) -, -CH (CH ₃ ) -CH ₂ -CH ₂ -CH ₂ -CH (CH ₃ ) -, preferably C ₃ -C ₅ -alkylene such as - (CH ₂ ) ₃ -, - (CH ₂ ) ₄ -, - (CH ₂ ) ₅ -.
n is an integer in the range of 1 to 4, in particular 2 or 3;
R ^{5 is the} same or different and selected from hydrogen,
C ₁ -C ₁₂ -alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec. Pentyl, neo-pentyl, 1,2-dimethylpropyl, iso-amyl, n-hexyl, iso -hexyl, sec-hexyl, n-heptyl, iso-heptyl, n-octyl, n-nonyl, n-decyl, and n-dodecyl; preferably C ₁ -C ₆ -alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec. Pentyl, neo-pentyl, 1,2-dimethylpropyl, iso-amyl, n-hexyl, iso-hexyl, sec-hexyl, more preferably C ₁ -C ₄ alkyl such as methyl, ethyl, n-propyl, iso-propyl , n-butyl, iso-butyl, sec-butyl and tert-butyl, most preferably methyl;
C ₃ -C ₁₂ cycloalkyl, substituted or unsubstituted, such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl and cyclododecyl; preferred are cyclopentyl, cyclohexyl and cycloheptyl; Examples of substituted cycloalkyl groups are: 2-methylcyclopentyl, 3-methylcyclopentyl, cis-2,4-dimethylcyclopentyl, trans-2,4-dimethylcyclopentyl 2,2,4,4-tetramethylcyclopentyl, 2-methylcyclohexyl, 3-methylcyclohexyl, 4- Methylcyclohexyl, cis-2,5-dimethylcyclohexyl, trans-2,5-dimethylcyclohexyl, 2,2,5,5-tetramethylcyclohexyl, 2-methoxycyclopentyl, 2-methoxycyclohexyl, 3-methoxycyclopentyl, 3-methoxycyclohexyl, 2-chlorocyclopentyl, 3 Chlorocyclopentyl, 2,4-dichlorocyclopentyl, 2,2,4,4-tetrachlorocyclopentyl, 2-chlorocyclohexyl, 3-chlorocyclohexyl, 4-chlorocyclohexyl, 2,5-dichlorocyclohexyl, 2,2,5,5-tetrachlorocyclohexyl, 2-thiomethylcyclopentyl, 2-thiomethylcyclohexyl, 3-thiomethyl-cyclopentyl, 3-thiomethylcyclohexyl;
C ₇ -C ₁₃ aralkyl, preferably C ₇ - to C ₁₂ phenylalkyl such as benzyl, 1-phenethyl, 2-phenethyl, 1-phenyl-propyl, 2-phenyl-propyl, 3-phenyl-propyl, neophyl (1- Methyl-1-phenylethyl), 1-phenyl-butyl, 2-phenyl-butyl, 3-phenyl-butyl and 4-phenyl-butyl, more preferably benzyl,
C ₆ -C ₁₄ aryl, substituted or unsubstituted, wherein substituted and unsubstituted C ₆ -C ₁₄ aryl radicals are as defined above.

In one embodiment of the present invention, R ⁵ with R ² or R ⁵ with R ⁴ or R ⁵ with R ³ or, in the case where n is greater than 1, in each case two adjacent radicals R ^{5 may be joined} together to form a ring. Thus, for example, R ⁵ and R ² together may be C ₁ -C ₈ -alkylene, unsubstituted or substituted by C ₁ -C ₁₂ -alkyl or C ₆ -C ₁₄ -aryl. Examples include: -CH ₂ -, -CH (CH ₃ ) -, - (CH ₂ ) ₂ -, -CH ₂ -CH (CH ₃ ) -, -CH ₂ -CH (C ₂ H ₅ ) -, - (CH ₂ ) ₃ -, - (CH ₂ ) ₂ -CH (CH ₃ ) -, - (CN ₂ ) ₂ -CH (C ₂ H ₅ ) -, - (CH ₂ ) ₂ -CH (C ₆ H ₅ ) -, - (CH ₂ ) ₄ -, - (CH ₂ ) ₅ -, - (CH ₂ ) ₆ , - (CH ₂ ) ₇ , -CH (CH ₃ ) -CH ₂ -CH ₂ -CH (CH ₃ ) -, -CH (CH ₃ ) -CH ₂ -CH ₂ -CH ₂ -CH (CH ₃ ) -, preferably C ₃ -C ₅ -alkylene such as - (CH ₂ ) ₃ -, - (CH ₂ ) ₄ -, - (CH ₂ ) ₅ -.

Most preferably, the radicals R ² to R ^{5 are} each hydrogen. Very particularly preferred is chosen as the compound of general formula I 2-methoxy-2,3-dihydro-4H-pyran (formula I.1).

Heated according to the invention one cyclic compound of general formula I in the presence of Water. The amount of water can be chosen within wide ranges, preferably are 20 to 1000 vol .-%, based on cyclic compound of the general Formula I, more preferably 50 to 500 vol .-%, especially 60 to 200% by volume are preferred.

The inventive method is practiced in Presence of an acid catalyst consisting of one or more acidic compounds can exist.

Suitable acidic catalysts are, for example, phosphoric acid, in particular orthophosphoric acid, formic acid, acetic acid, acidic silica gels, acidic aluminum oxide, sulfuric acid, sulfonic acids, for example methanesulfonic acid or para-toluenesulfonic acid. Also suitable are mixtures of, for example, sulfuric acid and phosphoric acid. If you work in non-aqueous solvents, then the application of P ₂ O ₅ or molecular sieve is conceivable. It is possible to use from 0.1 to 20% by weight of catalyst, based on the cyclic compound of the general formula I. Of course, you can still dilute the catalyst or catalysts before use in the process according to the invention, for example with water.

In an embodiment of the present invention the process according to the invention at acidic pH, i. for example, at a pH, in the range of 0 to 6.8, preferably 0.1 to 4 and especially preferably 0.5 to 4 lies.

In an embodiment of the present invention the process according to the invention at temperatures of 40 to 120 ° C, in particular 50 to 85 ° C out.

you can the inventive method at any pressure from 0.1 to 100 bar, preferably at atmospheric pressure.

When time for the heating is useful for 10 minutes to 24 hours, preferably one to three hours.

According to the invention you can in the presence of an organic solvent or a mixture of organic solvents, for example Toluene, petroleum ether or n-heptane, but the addition of solvent is not necessary. wishes one solvent is an amount in the range of 10 to 100% by volume, based on cyclic compound of general formula I, suitable.

In a preferred embodiment of the present invention the process according to the invention without adding ketone or monoaldehydes. Examples of ketones are acetone, methyl ethyl ketone or methyl isobutyl ketone, examples for monoaldehydes are acetaldehyde, benzaldehyde, crotonaldehyde and propionaldehyde.

During or after the heating, HXR ³ formed during heating is at least partially separated.

While carrying out the process according to the invention, HXR ^{3 is} formed, namely up to one equivalent per cyclic compound of the general formula I.

In one embodiment of the present invention, during the heating, ie during the reaction, HXR ^{3 is separated} off, for example by distillation, whereby the separated stream which contains HXR ³ and may further contain solvent only partially or not at all admixed.

In another embodiment of the present invention, first, without separating HXR ³ , it is heated, for example, to reflux or to a slightly lower temperature than the reflux, and after some time it begins to separate HXR ³ .

If HXR ^{3 is obtained} in crystalline form, it can be separated by filtration, preferably after completion of the reaction and cooling the reaction mixture to room temperature, for example.

It is also possible to heat in the context of the present invention first, without separating HXR ³ , and then at least partially separate HXR ³ by applying reduced pressure.

In the context of the present invention, at least partial removal of HXR ³ is to be understood as meaning that at least 30 mol%, preferably at least 85 mol% and particularly preferably at least 95 mol% of the HXR ³ formed during the process according to the invention are separated off. It is possible to remove HXR ³ quantitatively, which is particularly preferred when HXR ^{3 has} toxicologically harmful properties.

In a variant of the process according to the invention, up to 99.5 mol% of the HXR ³ formed during the heating is separated off, in another variant up to 99.8 mol%.

In the separation of HXR ³ and water can be partially separated with. However, a quantitative separation of water is avoided in the context of the present invention.

By the inventive method receives one watery Formulations, which are also the subject of the present invention are and hereinafter also referred to as inventive aqueous formulations become.

Before, during or after the at least partial removal of HXR ³ according to the invention, the usually acidic aqueous formulations according to the invention can be completely or partially neutralized. For neutralizing, for example, basic alkali metal salts are suitable, such as alkali metal hydroxides, alkali metal carbonates and alkali metal hydrogencarbonates. Particularly suitable are basic salts of sodium and potassium. Also suitable are basic salts of magnesium such as magnesium oxide.

In some cases is during the implementation the method according to the invention observed the formation of a multiphase mixture. In the mentioned make Is it possible, the respective aqueous Phase by, for example, decantation or other known per se Methods to remove.

wobei in Formel II die Variablen wie folgt definiert sind:
R⁷ sind verschieden oder vorzugsweise gleich und gewählt aus
C₁-C₄-Alkyl, Methyl, Ethyl, n-Propyl, iso-Propyl, n-Butyl, iso-Butyl, sec.-Butyl und tert.-Butyl, ganz besonders bevorzugt Methyl,
und insbesondere Wasserstoff.
x ist eine ganze Zahl im Bereich von 1 bis 250, bevorzugt 3 bis 50, besonders bevorzugt 5 bis 20.
y wird gewählt aus Null oder 1.In a preferred embodiment of the present invention, cyclic compound of the general formula I is heated in the presence of at least one compound of the general formula II

where in formula II the variables are defined as follows:
R ⁷ are different or preferably the same and selected from
C ₁ -C ₄ -alkyl, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl, very particularly preferably methyl,
and especially hydrogen.
x is an integer in the range of 1 to 250, preferably 3 to 50, more preferably 5 to 20.
y is chosen from zero or 1.

Examples of compounds of the general formula II are ethylene glycol, propylene glycol, glycerol, diethylene glycol, dipropylene glycol, diglycerol (R ⁷ = hydrogen, x = 2, y = 1), triethylene glycol, tetraethylene glycol and polyethylene glycols, for example polyethylene glycols having on average 8 to 25 ethylene oxide units ( Number average), further mixed polyalkylene oxides, which are obtainable for example by reaction of mixtures of ethylene oxide and propylene oxide and optionally butylene oxide. Polyethylene glycol having on average 7 to 12 (number average) ethylene oxide units and glycerol are particularly preferred.

Do you wish according to the invention in the presence of at least one compound of the general formula II to heat, so you can in the range of 3 to 300 wt .-%, preferably 5 to 200 Wt .-% and particularly preferably 10 to 50 wt .-% compound of the general Choose Formula II, based on cyclic compound of general formula I.

One Another object of the present invention are aqueous formulations, available according to the inventive method.

Aqueous formulations according to the invention can have a water content of 5 to 80 wt .-%, preferably 20 to 50% by weight. The 100 wt .-% missing remainder of the formulations of the invention is in the context of the present invention also as active ingredient content the formulations according to the invention called from the reaction of the invention described above resulting reaction products, optionally in a mixture with unreacted cyclic compound of general formula I and optionally in admixture with compound of the general formula II, as active ingredients.

Aqueous formulations according to the invention can have a pH of 2 to 9, preferably from 3 to 7, especially preferably 4 to 6.

beispielsweise bis zu 10 Gew.-%, und im Wesentlichen beispielsweise durch Aldolkondensation gebildete Dimere, Oligomere und Polymere von Dicarbonylverbindung der allgemeinen Formel III. It can be demonstrated, for example by mass spectrometry, that aqueous formulations according to the invention contain only small amounts of dicarbonyl compound of the general formula III

for example, up to 10% by weight, and dimers, oligomers and polymers of dicarbonyl compound of general formula III, formed essentially for example by aldol condensation.

Another object of the present invention are mixtures of dimers, oligomers and polymers of compound of general formula III, which may be contaminated by small amounts, for example up to 10 wt .-% of compound of general formula III. Mixtures of dimers, oligomers and polymers according to the invention can be obtained by the preparation process according to the invention and subsequent isolation according to methods known per se, for example removal, in particular evaporation of water. Mixtures of dimers, oligomers and polymers of compound III according to the invention can have a broad molecular weight distribution, the average molecular weight M _{n can be} in the range from 100 to 100,000 g / mol, preferably from 200 to 10,000 g / mol, and the quotient M _w / M _{n is} in the range from 2 to 20, preferably from 2.1 to 10.

Inventive mixtures of dimers, oligomers and polymers of compound of the general Formula III can be used without further processing or as an aqueous formulation for the production of semi-finished and of leather and as a preservative use, directly or as a powdered formulation.

One Another object of the present invention is the use the aqueous according to the invention Formulations for the production of semi-finished products and of leather. Another object of the present invention is a method for the manufacture of semi-finished or leather using at least an aqueous according to the invention Formulation.

In an embodiment The present invention aqueous formulations in the Pre-tanning, tanning or retanning used by animal skins.

Further objects The present invention relates to the use of aqueous formulations according to the invention for retanning, tanning or retanning animal skins and a method for Pre-tanning, tanning or retanning animal hides using aqueous according to the invention Formulations.

The inventive method for pretanning, tanning or retanning animal skins, hereinafter also tanning method according to the invention called, starts from pretreated by conventional methods flay from animals such as cattle, pigs, goats or deer. It is for the tanning process according to the invention not essential if the animals were killed, for example, by slaughtering or natural Causes have died. To the conventional methods of pretreatment belong for example, the limp, deliming, Pickling and pimples as well as mechanical work steps, for example for defloaming the skins.

The Tanning process according to the invention becomes common in the presence of water.

The Tanning process according to the invention is practiced, for example such that one or more inventive aqueous formulations in a Portion or in several portions immediately before or during one Tanning step added.

The Tanning process according to the invention is preferably carried out at a pH of 2.5 to 4, wherein you often observed that the pH during the implementation the tanning process according to the invention increases by about 0.3 to three units. You can change the pH by Increase addition of blunting agent by about 0.3 to three units.

The Tanning process according to the invention is practiced in Generally at temperatures in the range of 10 to 45 ° C, preferred in the range of 20 to 30 ° C out. proven has a duration of 10 minutes to 12 hours, are preferred one to 3 hours. The tanning process according to the invention can be found in any tannery usual Carry out vessels, for example by walking in barrels or in rotatable drums with internals.

In a variant of the tanning process according to the invention one or more aqueous formulations according to the invention together with one or more conventional ones Tannins, for example, with chrome tannins, mineral Tannins, syntans, polymer tanning or vegetable tannins, as described for example in Ullmann's Encyclopedia of Industrial Chemistry, Volume A15, pages 259-282 and in particular Page 268 ff., 5th edition, (1990), Verlag Chemie Weinheim. The weight ratio of the formulation according to the invention conventional Tanning or sum of conventional Gerbstoffe is expedient of 0.01: 1 to 100: 1. In an advantageous variant of the method according to the invention If you set only a few ppm of conventional tanning the formulations of the invention to. However, it is particularly advantageous to the admixture conventional Tanning agents for formulations according to the invention completely to renounce.

In a variant of the tanning process according to the invention one sets one or more aqueous formulations of the invention in one Portion or in several portions before or during pre-tanning, in a special variant already in the pimple.

In Another variant of the tanning process according to the invention is used one or more aqueous formulations according to the invention in one portion or in several portions before or during one Retanning step to. This variant will also be explained below as Nachgerbverfahren invention designated. The retanning process according to the invention comes from pre-tanned skins, which are also referred to as semi-finished products. This one treats with the aqueous according to the invention Formulations.

you can the Nachgerbverfahren invention under otherwise usual Perform conditions. You choose appropriate one or more, for example 2 to 6 action steps and can between the Flush the reaction steps with water. The temperature at the individual action steps is in each case from 5 to 60 ° C, preferably 20 to 45 ° C. It is advisable to add more, while retannation is commonly used Medium, for example fatliquors, leather dyes or emulsifiers.

One Another aspect of the present invention are semi-finished and Leather produced by the tanning process according to the invention. Leather according to the invention and semifinished products according to the invention be using at least one aqueous according to the invention Formulated. Leather and semi-finished products according to the invention are characterized by an overall advantageous quality, for example, smooth Scars, more homogeneous tanning over the cross-section, improved tear strength and fullness as well less tendency to discolour, especially for yellowing.

In a special embodiment the tanning process according to the invention If one sets formulations of the invention in the form of powdered Formulations. Further objects of the present invention are therefore the use of aqueous formulations of the invention Production of powdery Formulations and a process for the preparation of powdered formulations using aqueous formulations according to the invention.

For the preparation of pulverulent formulations according to the invention, the procedure is, for example, such that at least one aqueous formulation according to the invention is dried, for example by Ver evaporation of the water and more preferably by spray drying.

In a particular embodiment In the present invention, at least one aqueous formulation according to the invention is mixed with one or more additives and then dried, for example by evaporation of the water and in particular by spray drying.

suitable Aggregates are usually solid particulate matter. To be favoured she chose from strength, Silica, for example in the form of silica gel, in particular in the form of spheroidal silica gels, Phyllosilicates, alumina and mixed oxides of silicon and Aluminum.

In a specific embodiment of the present invention, the procedure is as follows:
It has proven useful to first concentrate inventive aqueous formulations to a residual water content of 50 wt .-% or less. Furthermore, it is - so it is desired - one or more additives to. Then remove the remaining volatile components. Preference is given to spraying the resulting liquid, solid or oily concentrated formulations in a spray dryer, preferably in a spray tower. Spray dryers are known to the person skilled in the art and are described, for example, in Vauck / Müller, Basic Operations of Chemical Process Engineering, VCH Weinheim, 1988, 7th Edition, pp. 638-740 and pp. 765-766, and in the literature cited therein.

Another object of the present invention relates to powdered formulations containing
From 10 to 100% by weight, preferably from 40 to 90% by weight of active compound,
and 0 to 90 wt .-%, preferably 10 to 60 wt .-% of one or more additives.

The powdery formulations according to the invention can of fine particles with a mean particle diameter of 100 nm to 0.1 mm exist. The particle diameters follow a particle diameter distribution that can be narrow or wide. Also bimodal particle size distributions are conceivable. The particles themselves can become irregular or more spherical Be in shape, being spherical Particle forms are preferred. The powdered formulations of the invention leave in the tanning process according to the invention Dosing and becoming very hygienic instead of inventive aqueous Formulations used.

It it was furthermore found that aqueous formulations according to the invention and pulverulent formulations according to the invention have biocidal activity.

One Another aspect of the present invention relates to the use the aqueous according to the invention Formulations and the pulverulent formulations according to the invention for preservation as well as preservatives, containing inventive powdery or aqueous Formulation. The preservatives of the invention are suitable for the preservation of products, such as cosmetic Products, and of surfaces.

The Invention is illustrated by examples.

1. Preparation of the aqueous according to the invention Formulations 1.1 to 1.3

The molecular weight determinations were made by gel permeation chromatography.
Stationary phase: poly (2-hydroxyethyl methacrylate) gel mixed with ethylene glycol dimethacrylate, commercially available as HEMA BIO from PSS, Mainz, Germany.
Eluent: Mixture of 30 wt .-% tetrahydrofuran (THF), 10 wt .-% acetonitrile, 60 wt .-% 0.1 molar aqueous NaNO ₃ solution
Internal standard: 0.001% by weight of benzophenone
Flow: 1.5 ml / min
Concentration: 1% by weight in eluent with internal standard
Detection: UV / vis at 254 nm
Calibration with polystyrene sulfonate calibration part of the company PPS.

1.1. Preparation of aqueous Formulation 1.1

In a 2-liter three-necked flask with condenser, stirrer and thermometer was added 200 g of 2-methoxy-2,3-dihydro-4H-pyran (Formula I.1, 2 moles), 30 g of polyethylene glycol having an average molecular weight M _n of 400 g / mol, 200 ml of water and 6.5 g of a 50 wt .-% aqueous sulfuric acid and 3 hours at 77 ° C. heated. The pH was 1.

Subsequently was at 35 ° C chilled and then with 25 wt .-% aqueous Sodium hydroxide adjusted to a pH of 5. Subsequently was at 56 ° C heated and stirred at a pressure of 150 mbar for 3 hours and aqueous Separated methanol.

400 g of aqueous formulation 1.1 according to the invention were obtained.
M _n : 580 g / mol, M _w : 1363 g / mol, M _w / M _n : 2.58

1.2. Preparation of aqueous Formulation 1.2

In a 1 liter three-necked flask with condenser, stirrer and thermometer 300 g of 2-methoxy-2,3-dihydro-4H-pyran (Formula I.1, 2.9 mol), 200 ml of water and 4.2 g of 50 wt .-% sulfuric acid mixed and 1 hour at 80 ° C heated. The pH was 1.

Subsequently was at 35 ° C chilled and then with 18 g 10 wt .-% aqueous Sodium hydroxide adjusted to a pH of 6. Subsequently was at 35 ° C up to 45 ° C and a pressure of 80 to 100 mbar for 3 hours and stirred aqueous Separated methanol.

370 g of aqueous formulation 1.2 according to the invention were obtained
M _{n w} 326 g / mol, M: 660 g / mol, M _w / M _n: 2.02

1.3. Preparation of aqueous Formulation 1.3

In a 1 liter three-necked flask equipped with condenser, stirrer and thermometer were added 300 g of 2-methoxy-2,3-dihydro-4H-pyran (Formula I.1, 2.9 moles), 200 ml of water and 6.7 g of 50 Wt .-% sulfuric acid and heated to 80 ° C for 1 hour. The pH was maintained at 0.5 during the reaction by addition of further sulfuric acid. The mixture was then cooled to 30 ° C and then adjusted to a pH of 6 with 33 g of 10 wt .-% aqueous sodium hydroxide solution. The mixture was then stirred at 30 ° C and a pressure of 60 to 70 mbar for 3 hours and separated off aqueous methanol. 300 g of aqueous formulation 1.3 according to the invention were obtained
M _n : 400 g / mol, M _w : 455 g / mol, M _w / M _n : 2.39

2. Gerbversuche invention 2.1 to 2.3 and comparative experiment

information in% by weight refers to the pickle weight, if not otherwise specified.

strip each weighing 2500 g of barked beef with one split thickness of 2.5 mm were at a pH of 3.0-3.2 and 25 ° C in one 10-liter drum with 750 ml of water and, based on the Pickelblöße, 3 wt .-% an aqueous according to the invention Formulation according to example 1.1. offset to 1.3. After a walk time of 60 minutes were 2% by weight of the sulfone tanning agent from EP-B 0 459 168, Example K1 added and another 2 hours. Subsequently, with 0.5 wt .-% magnesium oxide within 6 hours the pH is set to 4.9-5.1. The fleet was drained and the skin washed with 300 ml of water. To the wilting became the skins folded to 1.6-1.8 mm. The semi-finished products according to the invention were obtained 2.1 to 2.3.

The Foldability was determined by tests on a folding machine. The folding machine works with rotating knives. In worse Folding smeared the knives across the surface, it came to a temperature increase on the surface the leather, so that a horn-like melting irreversibly damaged the skin. The Grading was graded from 1 (very good) to 5 (inadequate).

Of the Comparative experiment V2.4 was carried out analogously, but the adduct according to the invention by 3 wt .-% glutaraldehyde (50 wt .-% aqueous solution) replaced.

The shrinking temperatures were determined according to the procedure of DIN 53 336 (year 1977), the procedure being modified as follows:
Point 4.1: The specimens had the dimensions 3 cm x 1 cm; the thickness was not determined.
Point 4.2: only one instead of 2 samples per leather sample was tested.
Point 6: accounted for
Point 7: the drying in the vacuum desiccator was omitted.
Item 8: When the pointer dropped, the shrinkage temperature was measured.

The Grading of the hilt and the yellowing was as in the School: 1 very good, 2 good, 3 satisfactory, 4 adequate.

Table 1: Result of tanning and analytical evaluation of the semi-finished products according to the invention

3. Preparation of leather according to the invention and comparative experiment

information % by weight refers to the shaved weight, unless stated otherwise.

3.1. Production of the leather 3.1 semi-finished product 2.1

1800 g semifinished product 2.1 was drummed together with the following agents for 20 minutes:
120 Gew. -% water, 5 Gew. -% of the Sulfongerbstoffs from EP-B 0 459 168, example K1 and
4% of a 30 wt .-% aqueous, partially neutralized NaOH solution of a methacrylic acid homopolymer having the following analytical data: M _n about 10,000; K value according to Fikentscher: 12 (determined as 1% by weight aqueous solution), viscosity of the 30% by weight solution: 65 mPa · s (DIN EN ISO 3219, 23 ° C.), pH 5.1.

Then, 6 wt .-% were of the vegetable Tara ^® (BASF Aktiengesellschaft) and 2 wt .-% of the resin tanning agent Relugan ^® S (BASF Aktiengesellschaft) and 2 wt .-% dose of an aqueous solution of dyes, whose solids had the following composition :
70 parts by weight of dyestuff from EP-B 0 970 148, Example 2.18,
30 parts by weight of Acid Brown 75 (iron complex), Color Index 1.7.16.
dosed and the mixture drummed. After two hours, the pH was adjusted to 3.6 with formic acid. As fatliquoring 6 wt .-% were of a fatliquoring agent (s. 4) and 1 wt .-% Lipamin OK ^® (BASF Aktiengesellschaft) were added. After a drumming time of a further 60 minutes, the pH was adjusted to 3.2 with formic acid. Before draining the fleet, a sample of the fleet was drawn. The fleet was abandoned.

The thus obtained leather was washed twice with 100 wt .-% water, overnight stored damp and dried after Abwalken on the tenter at 50 ° C. Leather 3.1 was obtained. After the tunnel, leather 3.1 was like below assessed standing.

The Rating was based on a grading system from 1 (very good) to 5 (inadequate). The evaluation of fleet consumption was done visually according to the criteria residual dye (extinction) and turbidity (fatliquoring agent), from which the mean was formed.

Examples 3.2 to 3.3, Comparative Example V3.4

The The above example was repeated, but in each case with the semifinished products according to the invention 2.2 to 2.3. For Comparative Example V3.4 became the semifinished product of Comparative Example V2.4 further processed. The evaluation of the application technology Properties can be found in Table 2.

Table 2

The Tensile strength was determined according to DIN 53328.

The stitch tear was determined according to DIN 53331.

4. Preparation of the fatliquoring agent for the Examples 2.1 to 2.3 and V2.4

In a 2-liter kettle were mixed:
230 g of a polyisobutene with M _n = 1000 g / mol and M _w = 2000 g / mol,
30 g of nC ₁₈ H ₃₇ O- (CH ₂ CH ₂ O) ₂₅ -OH
5 g of nC ₁₈ H ₃₇ O- (CH ₂ CH ₂ O) ₈₀ -OH
40 g of oleic acid
230 g sulfited oxidized triolein

The mixture was heated with stirring to 60 ° C and 470 g of water and 10 g of nC ₁₆ H ₃₃ O- (CH ₂ CH ₂ O) ₇ -OH added. The resulting emulsion was then passed through a gap homogenizer. A finely divided, stable emulsion was obtained.

Claims (19)

Process for the preparation of aqueous formulations, characterized in that at least one cyclic compound of general formula I

heated in the presence of water and of an acidic catalyst and at least partially separated during or after the heating HXR ³ , wherein in the formula I, the variables are defined as follows: X selected from oxygen, sulfur and NR ⁶ , R ³ , R ^{6 are the} same or different and selected from C ₁ -C ₁₂ -alkyl, C ₃ -C ₁₂ -cycloalkyl, substituted or unsubstituted, C ₇ -C ₁₃ -aralkyl, C ₆ -C ₁₄ -aryl, substituted or unsubstituted, formyl, CO -C ₁ -C ₁₂ alkyl, CO-C ₃ -C ₁₂ cycloalkyl, substituted or unsubstituted, CO-C ₇ -C ₁₃ aralkyl, CO-C ₆ -C ₁₄ aryl, wherein in the event that X is NR ⁶ , R ³ and R ⁶ may be linked together to form a ring; R ¹ , R ² , R ^{4 are} identical or different and selected from hydrogen, C ₁ -C ₁₂ -alkyl, C ₃ -C ₁₂ -cycloalkyl, substituted or unsubstituted, C ₇ -C ₁₃ -aralkyl, C ₆ -C ₁₄ - Aryl, substituted or unsubstituted, wherein each two adjacent radicals may be connected together to form a ring; n is an integer in the range of 1 to 4; R ^{5 is} identical or different and selected from hydrogen, C ₁ -C ₁₂ -alkyl, C ₃ -C ₁₂ -cycloalkyl, substituted or unsubstituted, C ₇ -C ₁₃ -aralkyl, C ₆ -C ₁₄ -aryl, substituted or unsubstituted, wherein R ⁵ with R ⁴ or also two adjacent radicals R ⁵ may be connected to each other to form a ring. Method according to claim 1, characterized in that that you do it without adding ketone or monoaldehyde. Method according to claim 1 or 2, characterized that X means oxygen. Method according to one of claims 1 to 3, characterized in that R ¹ , R ² , R ⁴ and R ^{5 are} each hydrogen. Method according to one of claims 1 to 4, characterized that n = 2 is chosen becomes. Method according to one of claims 1 to 5, characterized in that the heating in the presence of at least one compound of general formula II

where in formula II the variables are defined as follows: R ^{7 is the} same or different and selected from hydrogen and C ₁ -C ₄ -alkyl, x is an integer in the range from 1 to 250, y is selected from zero or 1. aqueous Formulations, available according to a method according to one of claims 1 to 6. Mixtures of dimers, oligomers and polymers of at least one dicarbonyl compound of the general formula III

wherein the variables are defined as follows: R ¹ , R ² , R ^{4 are} identical or different and selected from hydrogen, C ₁ -C ₁₂ -alkyl, C ₃ -C ₁₂ -cycloalkyl, substituted or unsubstituted, C ₇ -C ₁₃ - Aralkyl, C ₆ -C ₁₄ aryl, substituted or unsubstituted, wherein each two adjacent radicals may be connected together to form a ring; n is an integer in the range of 1 to 4; R ^{5 is} identical or different and selected from hydrogen, C ₁ -C ₁₂ -alkyl, C ₃ -C ₁₂ -cycloalkyl, substituted or unsubstituted, C ₇ -C ₁₃ -aralkyl, C ₆ -C ₁₄ -aryl, substituted or unsubstituted, wherein R ⁵ with R ⁴ or also two adjacent radicals R ⁵ may be connected to each other to form a ring. Mixtures according to claim 8, obtainable by a process according to one the claims 1 to 6 and then Removing water. Use of aqueous Formulations according to Claim 7 or mixtures according to Claim 8 or 9 for the production of semi-finished products and leather. Process for the production of semifinished products or Leather using watery Formulations or mixtures according to claim 8 or 9 according to claim 7th Use of aqueous Formulations according to claim 7 for the preparation of powdered formulations. Process for the preparation of powdered formulations using aqueous Formulations according to claim 7. Method according to claim 13, characterized in that that you have at least one aqueous A formulation according to claim 7 and optionally one or more Aggregates mixed together and then dried. The method of claim 14, wherein the one or more Aggregates selected be made of strength, Silica, phyllosilicates, alumina and mixed oxides of silicon and aluminum. Process for the preparation of powdered formulations according to claim 14 or 15, characterized in that they are passed through Spray drying wins. powdery Formulations, available according to one of the claims 13 to 16. Semi-finished and leather, manufactured using of at least one aqueous A formulation according to claim 7 or at least one powdered formulation according to claim 17. Use of powdered formulations according to Claim 17 or of aqueous Formulations or mixtures according to claim 8 or 9 according to claim 7 as a preservative.