CS196248B2 - Process for preparing pyrocatechinetheres - Google Patents

Abstract

1444967 Pyrocatechol ethers BASF AG 24 Oct 1973 [25 Oct 1972] 49403/73 Heading C2C The invention comprises a pyrocatechol ether of formula wherein R<SP>1</SP> is hydrogen or lower alkyl, R<SP>2</SP> is hydrogen or, lower alkyl which is unsubstituted or substituted by halogen, methoxy, ethoxy or benzyl; R<SP>3</SP> is lower alkyl, cycloalkyl, phenyl, #-chloroethyl, alkoxyalkyl, lower alkenyl, lower alkynyl or acyl; or R<SP>1</SP> and R<SP>2</SP> together with the carbon atom whose substituents they are or R<SP>1</SP> and R<SP>3</SP> together with the carbon and oxygen atoms whose substituents they are denote a five-membered or six-membered ring, 'lower' denoting radical containing up to 4 carbon atoms. These compounds may be obtained by reacting a compound of formula wherein Hal is Cl, Br or I, and R<SP>1</SP>, R<SP>2</SP> and R<SP>3</SP> are as specified above with a salt of pyrocatechol, or with pyrocatechol in the presence of a base. Depending upon the quantities of the reactants the reaction may proceed in two stages: in the first stage the intermediate compounds of the formula are produced which may be converted to the compounds of Formula I by reaction with a further amount of catechol.

Description

(54) Process for preparing pyrocatechin ethers

The invention relates to processes for the preparation of novel pyrocatechin ethers.

It is known from German Patent Specification No. 568 033 that alcoholic or phenolic hydroxy groups can react with vinyl, theryl or halogeneters to form alkali-stable acetates (see also Höuben-Weyl, Methoden der organlschen Chemie, Band 6/3, pp. 186-229).

It is further known (e.g., Ji Chem. S.oc. 1927, 1664; U.S. Patent No. 3,202,573) that, when attempting to partially alkalinize only one OH group of pyrocatechin, using pyrocatechin and an alkylating agent, it is obtained mostly unusable by-product diether.

It has now been found that the novel pyrocatechethyl ether of the formula I can be prepared in a simple manner in an excellent yield

OH

QJT (I) wherein R ¹ is hydrogen or C 1 -C 4 alkyl, R ² is hydrogen or, after 196248, halogen, methoxy or ethoxy substituted alkyl of 1 to 3 carbon atoms or benzyl, R ^{3 is} alkyl; 1-4 carbon atoms, cyclohexyl, β-chloroethyl, methoxyethyl, ethoxyethyl, alkenyl or alkynyl containing up to 4 carbon atoms, acetyl, for ¹ pionyl or phenyl, or R ¹ and R ² together with the carbon atom to which they are attached form cyclopentyl or cyclohexyl, or R ² and R ³ together with a carbon atom, respectively. the oxygen to which they are attached forms an optionally methyl substituted tetrahydrofuranyl or tetrahydropyranyl ring, such that the pyrocatechin is reacted with an ether of formula II

R - O - R ³ (II), wherein R is vinyl optionally substituted with 1 to 3 carbon atoms or a radical of formula

R ¹ —C — Hal,

R ² wherein Hal is a chlorine, bromine or iodine atom

R ¹ , R ² and R ³ are as defined above, at room temperature, up to 80 ° C in an inert solvent in the presence of an acid catalyst in the reaction with vinyl ether, respectively. in the presence of a base in the reaction are! _{-halogenethe-:} rem. : -..................... —- ......

The catalysts used are acidic reactants such as; mineral acids, sholf acids, organic acids, α-haloether, organic and inorganic acid chlorides, ion exchangers, Lewis acids such as AlCl 3, FeCl 3, BF 3 and the like. The reaction is optionally carried out with the addition of a solvent or diluent inert to the reaction compo. nents such as ethers such as diethyl ether; tetrahydrofuran, dioxane, hydrocarbon, such as n-hexane, benzene, toluene, xylene, halogenated hydrocarbons, such as dichloro. . . methane, chloroform and carbon tetrachloride.

The novel compounds are important intermediates for the preparation of active substances for plant protection and pharmaceutical applications. of veterinary products.

An example of the reaction of pyrocatechin with vinyl methyl ether is the reaction according to the following equation:

OCoh ⁺ ^ ^'0 - ^EHA

Preferably, one of the above compounds is used as the catalyst.

Further, the compounds of the present invention can be prepared by reacting preferably equimolar amounts or up to 50% excess or deficiency of the α-haloether of the formula

R 1 hal — C — OR ³

AND

R2> and ^oH / ^s ...

wherein hal is Cl, Br or J and the radicals R ¹ , R ² and R ³ are as defined above, with the pyroca salt. techine or with pyrocatechin in the presence of an organic or inorganic base (e.g. an alcoholate, an alkali metal hydroxide or an alkaline earth metal or a suitable amine), or an alkaline-acting compound such as an alkali metal or alkaline earth metal carbonate. ~ - - - -Reaction is represented by the following equation:

R <

• »Ct ~ C-OR ³ -HCt * +: 'Л ² *

Residues Ri. R ² : a, R ³ are as defined above, and is preferably carried out with dilution of reagents / solvents with solvents such as 5 to 80 rays; % of an ether such as diethyl ether, tetrahydrofuran, or an aromatic hydrocarbon such as benzene, toluene or xylene. The wool ethers or α-halo ethers used for the reaction are known in the literature and are technically readily available [see, e.g., W. Reppe et al., Ann. 601, 98 (1956)].

In the above process, depending on the excess of ether used, respectively. α-haloether corresponding to the new bisethers of formula III

R ⁴ -C or ³ k *

-c- ° R ^ (H)

wherein the radicals R ¹ -R ² and R ³ are as defined above. ¹ ·;,. , '- +.

In quantitative yield, the abovementioned bisethers can be prepared preferably by reacting pyrocatechin with at least twice the amount of vinyl ether.

In this method, catalysts and reaction conditions such as temperature and solvent are used in the same manner as in the preparation of the compounds of formula I. ;

The novel pyrocatechin derivatives of formula I are colorless oils which, after stabilization with organic or inorganic bases, can be distilled under vacuum without decomposition. The following table gives an overview of the prepared compounds.

Formula I:

R ¹ R ² R ³ H н СНз H н С2Н5 H СНз СНз H СНз С2Н5 H СНз П-СЗН7 H СНз I-C3H7 H СНз 1-С4Н9 H СНз Ή СНз H СНз СОСНз H СНз СОС2Н5 H СНз —СН2 — СН = СНг H СНз —СНг — С = СН СНз / H СНз —Сн. 7: * '' к * ·  '·' С ^ СН ·· H СНз -СН2-СН2 — ОСНз H СНз - СН2 — СН2 — ОС2Й5 H CH2Cl —СНз H CH2Cl —С2Н5 H CH2Cl —CH2 --CH2 Cl H CH2Č1 • СОСНз H СНгВг • СНз H CH2J СНз H С2Н5 снз: · H С2Н5 C2H5 H С2Н5 СН2 — CsCH H СН2 — СН2С1 С Из H —СН2 — CHCI — СНз СНЗ H СН2 — СНВг — СНз СНз H —С Hz — CHCI — С2Н5 сПз H П-СЗН7 СНз ^: H I-C 5 H 7 СНз H СН = СЦ2 СНз H С ^ СН СНз H СН 2 - С = СН СНз H СНз СНз СНз СНз СНз СНз С2Н5 СНз CH2Cl СНз СНз CH2Cl С2Н5 СНз СНгВг СНз СНз СНгВг С2Н5 СНз?: ·· • С2Н5 СНз СНз П-С3Н7 СНз СНз i-C3H7 СНз С2Н5 С2Н5 СНз

Mp ° C; n _p 25

t. V.53.5Pa · 89-93

tv _n , 3P _a : 90-100

tv ₆₆ , ₇ p _a : 85-90

V-1333p _and 78-81

t. ⁱⁿ -i33,3p _and ⁹⁶ to 98

tvi33 _; 3p _a : 89-94

tv ₂ 6.7p _a : 94-98

tv ₂₆ .7p _a : 128 to 135 t · v.s33,3p _a : 132 to 136 n _D ²⁵ : 1.5075 n _D ²⁵ : 1.4905 n _D ²⁵ : 1.5135 n _D ²⁵ : 1.5146 no ²⁵ : 1.4975

По ²⁵ '· 1.5012 n _D ²⁵ : 1.5340'

tv ₂ oop _a : 105 to 113

t. in _6-6?, 7? _and: 100-103 n _D ^25: 1.5023

tv ₅ 3.3p _a : 80 to 95

TV _{40 and} p: 95-100 n _D ^25: 1.5024

Rl

R ²

H, n-CsH7

Η n-CdHg

Η ί-ΟΐΗθ

Formula III:.

R ³

CH3

CH3

CH3

GH3

CH3

Λ. O ~ C ~ OR * cC

Q-C-OR * R

Mp ° C; n _D ²⁵

tv ₆ · ^: 115 -up. 118 _{t. ^V-} 26,7p _{<and 95 and 1} 08 t. V.2opa: 97 to 108 tons. Vmax: 98-105

V-24.7Pa · 108 to 111 nD25; 1.5239 • nD 5: 1.5169 n _B 25: 1.5158

HH

HCH3

HCH3

HCH3

СЙзCH3

C2H5-C4H9

- Y * 53.3Pa · 105 to 109

tv _a6 9p _a : 99 to 105

tv4op _and : 97 to 102

t. V. * »»: 124 'to 128

The novel compounds are of great importance as starting materials. substances for the preparation of plant protection products and pharmaceutical preparations.

Thus, for example, active compounds which are good insecticides and which can be prepared by reaction with the compounds of the formula I with methyl isocyanate. they are excellent against both voracious, so-sucking insects, as well as against mites and ticks. At the same time, these compounds show very low phytotoxicity. The effect comes quickly and has a long duration. Thus, these compounds can be used to protect plants and combat harmful absorbent and voracious insects

Claims (1)

and fly, then - - also. in the veterinary medicine sector - against. mites (Acarina). Especially excellent effect of these substances is in mites strains that are resistant to phosphoric acid esters. Example 10-o- (1-methoxy) -ethoxyphenyl-N- -methylcarbamate 34 parts by weight of -o- (1-methoxy) -ethoxyphenol are dissolved in 100 parts by weight of toluene and 12 parts by weight of methyl isocyanate are added in one portion. -After. addition of 2 drops of trlethylamine. The reaction mixture is allowed to stand overnight, then concentrated and the oily residue is mixed with 100 parts by weight of a mixture of equal parts of toluene. and petroleum ether. ' By cooling, 33 parts of colorless crystals are separated. The product was obtained after recrystallization. mp 97-99 ° C. ^: ' Example 1 ' 2 ' -flo- (1-ethoxy) -ethoxyphenyl-N-methylcarbamate 33.4 pbw of pyrocatechin mono-N-methylcarbamate are suspended in 100 pbw of toluene. After '3' drops of concentrated 'hydrochloric acid' was added, 15 parts by weight of the wine were added dropwise over a period of 10 minutes. The reaction mixture was then stirred at 80 ° C for one hour. After cooling, the mixture was washed with 50 parts by weight of a 3% solution. NaHCO 3, dried over Na 2 SO 4. Evaporation of the solvent 'gave a colorless oil which was ^dissolved,' 100 'materials, parts, mixture of equal parts of toluene and petroleum ether. 31 parts by weight of carbamate crystallize in the freezer. After recrystallization, the product should be 62-63 ° C. AT For example, the compounds listed in the following table were prepared in a corresponding manner: J ⁴ CH ₃ . .. ^ jTO-CR *. · O r ⁶ :; R7 R ⁴  - 'R5 / ; ·. R6. 'T. 't. ⁰ Č''S H ’CH5  · H. ' •. , i-C3H7 40 to 45 H C2H5 h GH3 88 to '90 H C2H5 , 'H C2H5 52 to 54; H C3H7 H . 'CH 3 -. H C3H7 H C2H5 -, H . n-C4Hg H CH3 H ... . П-С4Й9 H . C2H5 H I-C 4 H 9 H CH3 H n-C 5 H 11 H CH3 H CH5 CH3 CH3 80 to '82 H . CH3 CH3 C2H5. H C2H5 . CH3 : CH3 CH3 OH3 . H CH3 · - ' Next new of the active compound they are e.g. pos: о ~ со ‰> ³ Aro-c; ^: QR ^e R7. R4 R5 R6 Mp ° С (^ 25) H H CH2Cl C2H5 (1,5125) H H CH2C1 ' COCH3 (1,5119) CH3 H CH2Cl C2H5 (1,5205) CH3 H · CHžBr CH3 (1,5310) H . H CHzBr  CH3 70 to 72 H H CH2J CH5 (1,5465) CH3 H CH2J CH3 . . ··· '...? H ' H CH 2 —CH 2 Cl CHs 65 to '66' CH3 H CH 2 —CH 2 Cl CHs - '' · · ''''' ^: 6 'H H CHCl-CH3 CH3 H H CHBrCH3 CH3O H H CH 2 —CH 2 Br CH3 19В248 9 10 R ^{7 R} 4 R ⁵ ··· R « Mp ° C (n _D 25) H H .-- GH2OGH3 GH3- · -. ·. . . .. GHs H GH2 — OGH3 ČH3 H H GH — GH — OGHs GH3 (1,5184) H H GH (OGHs) —GHJ GHs · · H H GOGH3 GH3 H '- ·· GH3 GHžGl GH3 106 to 108 CHj: GH3 GHžGl GH3 H GH3 GHzBr GH3 GH3 GH3 GHzBr · - GH3 H H CH2-SGH3 GH3 P-1 adjl · Example 3 (a) o- (1-methoxyethoxy) -phenol -