NO770428L - ACYLOXY-2, N-ACYLACETAMIDES AND PROCEDURES FOR THEIR PREPARATION. - Google Patents

Description

2-acyloxy-N-acylacetamides and process for their preparation.

The invention relates to new multifunctional compounds, namely 2-acyloxy-N-acylacetamides and a method for their preparation by reacting one or more acid anhydrides with one cyanohydrin f. in the presence of an acid catalyst.

2-acyloxy-N-acylacetamides according to the invention have the formula: . 5

where R-^ and R^> which may be the same or different, are selected from linear or branched alkyl groups with 1 to 11 C atoms and hydrocarbon groups with 6 to 12 C atoms containing at least one aromatic nucleus, : Rp and R^ which may be the same or different, are selected from H, linear alkyl groups of 1 to 12 C atoms, branched alkyl groups or cycloalkyl groups of 3 to 12 C atoms, hydrocarbon groups of 6 to 12 C atoms and containing at least one aromatic nucleus, or together form a linear or branched alkyl group with 3 to 11 C atoms, said groups may optionally be substituted with groups such as ethylene, chlorine, bromine, fluorine, iodine, nitro, hydroxy, alkoxy, acid groups, esters or amide carboxyl, ether oxide , primary amine, sec. or tart. amine, amine oxide, acetal, epoxy, sulfoxide, sulfone, acid sulfone. It has long been known that cyanohydrins can be esterified with carboxylic acid anhydrides to produce oc-acyl-oxynitriles.

It is also known that N-substituted amides can be prepared by reacting carboxylic acids with nitriles. However, this reaction requires high temperatures even in the presence of catalysts.

However, the applicant has now surprisingly discovered that the two reactions can be carried out at the same time at low temperature by the action of one or more carboxylic acid anhydrides on

a cyanohydrin in the presence of one acid catalyst and is then led to arrive at a new class of compounds, namely 2-acyloxy-N-acylacet-amide.

Cyanohydrins which are suitable for carrying out the present invention can, for example, be cyanohydrins of the following carbonyl compounds: formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, n-pentanal, pivalaldehyde, oenantal, 2-ethylhexanal, A-3 tetrahydrobenzaldehyde, hexahydrobenzaldehyde, 5-norbornene carboxaldehyde, tetrahydropyran 2-carboxaldehyde, benzaldehyde, monochlorobenzaldehyde, p-nitrobenzaldehyde, p-chloroprop-pioJialdehyde, p-methoxypropionaldehyde, 4~cyano-2,2-dimethyl-butyraldehyde, acetone, 2-butanone, 2-Pentanone, 3-Pentanone, methyliso-propylacetone, methylisobutylacetone, ethylamylketone, methylcyclohexylketone, acetophenone, benzophenone, cyclobutanone, cyclopentanone, cyclohexanone, 2-^methyl-cyclohexanone, 3-methyl-cyclohexanone, 4~methyl-cyclohexanone, 2,4 -diethyl-cyclohexanone, 3»'3».5'-trimethyl-cyclohexanone, tsophorone, cycloheptanone, cyclooctanone, cyclodecahon, cyclododecanone.

Carboxylic anhydrides can e.g. be of the following acids: acetic acid, propioric acid, butyric acid, isobutyric acid, valerian acid, caproic acid, heptanoic acid:, caprylic acid, capric acid, -lauric acid, benzoic acid.

The acid catalysts used according to the invention can be, for example*: sulfuric acid, hydrochloric acid, hydrobromic acid, perchloric acid, paratoluenesulfonic acid, phosphoric acid, zinc chloride, aluminum chloride, boron trifluoride.

For practical implementation of the invention is considered

two cases:

A) and R^ are equal:

The reactants are mixed in a liquid in the desired order.

The reaction is as follows:

where R - R^ R^ and Rg and have the indicated meaning.

However, the catalyst is preferably dissolved in the anhydride and the cyanohydrin is then gradually added.

■6

f

B) When R1 and R^ are mutually exclusive, one can proceed

as above using a mixture 'of anhydrides.

It is advantageous to carry out the turnover in two stages and convert them. two anhydrides R = R^ and then R R^with the cyanohydrin .

It is also possible to react a mixed anhydride

The reaction temperature is between 0 and 50°C and the optimum temperature which can be easily found by the person skilled in the art may vary depending on the reactivity of the reactants and the catalyst used.

The reaction participants are preferably used in stoichiometric conditions, but one or the other reactant can be added in excess or deficit. E.g. the carboxylic anhydride can be used in a molar ratio of 1:10 in relation to added cyanohydrin.

The catalyst used is used in an amount of 0.001 to 1$ on the basis of the total reaction mixture, preferably

0.01 to 0.1$.

The 2-acyloxy,N-acyl-acetamide compounds produced are solids which can be isolated by evaporation of reactant excess and purification in a known manner, e.g. omfcrystallization.

The new compounds form intermediates in organic synthesis, but can also find use as bleaching agents, where they act as low-temperature activators for persalts, particularly perborates and percarbonates.

The following examples illustrate the invention without limitation.

Example 1.

102 g of acetic anhydride (1 mol) and 0.1 g of sulfuric acid are filled into a container with a volume of 250 ml equipped with a stirrer. The temperature is kept at 10°C and 28.5 g of formaldehyde-cyanohydrin or -glyconitrile (0.5 mol) is gradually added over 25 minutes. Incubate for one hour at 10°C and leave the mixture for 24 hours at room temperature. The precipitated white solid is filtered and washed twice with 100 ml of ether. After drying, one has 69.6 g (yield = 87$) of 2-acetoxy-N-acetyl-acetamide, with melting point 3 rfSQ°G) The structure is confirmed by mass spectrometry, infrared analysis and NMR analysis.

Mass spectrometry: molecular peak M = 159

IR (CCl^): tfcnT<1>= 3420, 3000, 2950, 176O, 173O NMR 60mHz (CDCl^): 2.15~2.25PP» (6H), 4.87 ppm

(2H), 9.6 ppm (IH)

reference: TMS

Example 2

You go. proceed as in Example 1 and add 6.3 g of glyconitrile (0.1 mol) to 20.4 g of acetic anhydride (0.2 mol), containing 0.3 ml. perchloric acid. Moon isolate after treatment of the reaction mixture, 12.7 g of 2-acetoxy-N-acetyl-acetamide

(yield : 80$)

Example 3

One works as in Example 2 and reacts 21.36 lactonitrile (0.3 mol) and 61.2 g of acetic anhydride (0.6 mol) in the presence of 0.2 ml of perchloric acid. You get 5.2 g of 2-methyl-2-acetoxy-N-acetyl-acetamide (yield: 10%) with a melting point equal to 74°C and confirm the structure by IR and mass spectrometry.

Mass spectrometry: molecular peak M — 173

IR (CCL4) : Vcm"1 3420, 3000, 295O, I75O, 1720

Example, 4

One works as in Example 2, but replaces the glyconitrile with 42.5 g of acetone cyanohydrin (0.5 mol). You get 78 g of 2,2-dimethyl, 2-acetoxy-N-acetylacetamide (yield = 84$) with a melting point of 81°C and confirm the structure with mass spectrometry and NMR analysis*

Mass spectrometry: molecular peak M = 187

. NMR 60 mHz (acetone dg) ref.. HMDS

1.5 ppm (6H singlet) & = 2 ppm (3H, singlet) % " 2'3PPm (3H singlet) =9.7 ppm(lH singlet)

Example 5

Proceed as described in Example and add 5.7 g of glycolnitrile (0.1 mol) to 11.9 g of acetic anhydride (0.116 mol) containing 0.03 ml of perchloric acid. After the addition is finished, the acetic acid and the excess of acetic anhydride are removed by distillation (approx. 50°C, 10 mm Hg). 13 g of propionic anhydride (0.1 mol), 0.03 ml of perchloric acid are added to the evaporation residue and the mixture is reacted for 60 hours at room temperature. One can isolate 10.4 g (0.06 mol) of 2-acetoxy-N-propionyl-acetamide (yield = 50%). Melting point 101°G - NMR 60 mHz (acetone dg), ref. HMDS :

& 1 ppm (3H, triplet), 2.03 ppm (3H, singlet), '2.5 ppm

(2H, quadruple), 4.86 ppm (2H, singlet), 9.7 ppm (1H,

single).

Mass spectrum: molecular peak M = 173

IR (CCl^) : Cf cm"<1><=>3400, 2920, 1760, 1720

Example 6.

You work as described in Example 1. From propionic anhydride and glycolnitrile, you get 2-propionoxy^N-propionylacetamide (yield = 66.5$). Melting point 80°C, NMR , 60 mHz acetone dg, (ref. HMDS): = 4.9 ppm (2H, singlet)

h = 2.4 ppm (4H, quadruple) ^ 1.1 ppm (6 H triplet).

Example 7

Proceed as described in Example 5. Glyconitrile is reacted first with propionic anhydride and then with acetic anhydride to obtain 2-propionoxy-N-acetylacetamide (yield* 69$). Melting point 58°C 59°C, NMR 60 mHz acetone dg(ref. HMDS) å 5=5 4>9PPm (2H singlet) 3"2.2 ppm (5 H, massive)

& 1.1 ppm (3 H, triplet).

Claims (8)

1.. 2-acyloxy-N-acylacetamides with formula: where R^ and R^ which may be the same or different, are selected from linear or branched alkyl groups with 1 to 11 C atoms and hydrocarbon groups with 6 to 12 C atoms containing at least one aromatic nucleus, Rg and R^ can be the same or different and are selected from H, linear alkyl groups with 1 to 12 C atoms, branched alkyl groups or cycloalkyl groups with 3 to 12 C atoms, hydrocarbon groups with 6 to 12 C atoms and containing at least one aromatic nucleus or together form a linear or branched alkylene group with 3 to 11 C atoms, which groups may optionally be substituted with radicals such as ethylene, chlorine, bromine, fluorine, iodine, nitro, hydroxy alkoxy, acid, ester or carboxylic acid amide, ether oxide, primary, sec . or tart. amine, amine oxide, acetal, epoxy, sulf.oxide, sulfone, sulfonic acid. 2. Process for the preparation of compounds as stated in claim 1, where R-^ and R^ are equal by reaction, of an anhydride of formula: where R = R^ - R^ with a cyanohydrin of formula where R 2 and R 1 have the same meaning as in claim 1, in the presence of an acid catalyst. 3* Process for the production of compounds according to claim 1, where R-^ and R^ are different, by simultaneous or subsequent reaction of anhydrides of formula ; with a cyanohydrin of the form] ; where R^, Rg, R^ and R ^ had the same meaning as in claim 1, in the presence of an acid catalyst. 4. Process for the preparation of compounds as stated in claim 1, where R, and Ry. are different in turnover of a mixed anhydride of the form* D g a cyan hydrin .with formula where R^, Rg, R^ and R^ have the same meaning as in claim 1, in the presence of an acid catalyst. 5. Method as stated in claims 2-4, characterized in that the cyanohydrin is selected from cyanohydrins of the following compounds: formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, isobutyraldehyde, n-pentanal, pivalaldehyde, oenantal, 2-ethylhexanal, & -3 tetrahydrobenzaldehyde , hexahydrobenzaldehyde, 5-norDornen 2-carboxaldehyde, tetrahydropyran-2- carboxaldehyde, benzaldehyde, monochlorobenzaldehydes, p-nitro-benzaldehyde, p-chloropropionaldehyde, f?-methoxypropionaldehyde,- 4-cyah^-dimethyl-butyraldehyde, acetone, 2-butanone, 2-pentanone, 3-pentanone, methylisopropylketone, methylisobutylketone, ethylamyl -ketone, methyl cyclohexyl ketone, acetophenone, benzophenone, cyclobutanone, cyclopentanone, cyclohexanone, 2-methyl-cyclohexanone, 3_methyl- cyclohexanone, 4-methyl-cyclohexanone, 2,4-dimethyl-cyclohexanone, 3,3»5" trimethyl-cyclohexanone, isophorone, cycloheptanone, cyclooctanone, cycloacecanone, cyclododecanone, and said carboxylic acid anhydrides are selected from anhydrides of the following acids: acetic acid, propionic acid, butyric acid, isobutyric acid, valerian acid, caproic acid, heptanoic acid, f caprylic acid, capric acid, lauric acid, benzoic acid, and that the acid catalyst is selected from: sulfuric acid, hydrochloric acid, hydrobromic acid, perchloric acid, paratoluenesulfonic acid, phosphoric acid, zinc chloride, aluminum chloride and boron trifluoride. 6. Method as stated in claims 1 to 5, characterized in that the reaction is carried out at a temperature of 0 to 50°C. 7" Process as stated in claims 1 to 6,' characterized in that the catalyst is added in an amount of 0.001 to 1 by weight of the overall reaction mixture. 8. Method as stated in claim 6, characterized in that the catalyst is added in an amount of 0.01 to 0.1 weight-$ of the overall reaction mixture.