IL43480A - Pyrocatechol mono-ethers and their production - Google Patents

Description

and their production BASF 4163 The present invention relates to and valuable chol ethers and processes for their German Patent discloses that alcoholic or phenol hydroxyl groups are capable of reacting with vinyl or ethers with the formation of acetals which are stable to alkali also organischen volume pages 186 and 229 It is also known example from US Patent 202 573 that in an attempt to carry out a partia alkylation of only one hydroxyl group of pyrocatechol this latter and the alkylating agent are lost in considerable quantities due to the as of the We have found that the valuable new ethers of pyrocatechol having the formula for compounds in which R2 is ethyl or is hydrogen or lower alkyl to R2 is lower alkyl R3 substituted by halogen or is to cycloalkyl to or 1 3 7 lower alkenyl to lower alkynyl to 1 2 or lower or R and R together with the carbon atom whose substituents they denote a or 2 3 saturated or R and R together with the carbon and oxygen atom whose substituents they denote a or six membered saturated ring which is optionally substituted with methyl la are obtained in a sample manner and excellent yields when catechol is reacted with preferably the amount required for ification hydroxy1 group o a excess or deficiency of this of a vinyl ether of the where R is vinyl or vinyl bearing lower alkyl to as a and has the above with or without the addition of a substance such as an reacting a mineral acid organic organic or inorganic acid an ion exchanger or a Lewis for example and the in a temperature range of from to and preferably at to ith the addition of a solvent or diluent which is inert to the for example an ether te a hydrocarbon example toluene or halohydrocarbon or The new compounds are important intermediates for the production of active ingredients for plant protection agents and pharmaceutical and veterinary for Israel Patent Specification 42564 discloses the use of certain compounds of formula as intermediates in the of pesticidal If pyrocatechol is reacted with vinyl methyl the reaction may be illustrated by the following 8 ί The abovementioned compounds are preferably used as The products according to the invention may also be prepared by reaction of preferably equimolar amounts or an excess or ficiency of up to about of an of the 3 R 1 where Hal is Br or I and the radicals R R and have the above with a salt of pyrocatechol or with pyrocatechol in the presence of an organic or inorganic base example an alkali metal alkaline earth metal hydroxide or suitable or a substance having an alkaline such as an alkali or alkaline earth metal The following equation illustrates the 1 2 The radicals R R and have the above It is preferred to dilute the reactants with a for example from 5 to by weight of an ether or an hydrocarbon The vinyl ethers and used for the reaction are known from the literature and are also readily prepared industrially for example Reppe et 601 Depending on the excess of vinyl ether or used in the processes there are formed corresponding amounts of new bisethers of the formula The radicals R R and R have the above The bisethers may be prepared in quantitative yields preferably by reaction of pyrocatechol with at least twice the molar amount of a vinyl The catalysts and reaction conditions as regards temperature and solvents are analogous to those given for the production of compounds of formula Another process for the of compounds of the formula consists in reacting a bisether of the formula with catechol according to the following The radicals R2 and the catalysts and the conditions are the same as in the production of compounds of the formula from vinyl The new pyrocatechol derivatives of the formula and the pyrocatechol derivatives of the formula are obtained in the form of colorless oils which after stabilization with organic or inorganic bases can be distilled in vacuo without Compounds ich may be prepared by the process of the invention are listed Formula H CH 3 CH 3 H CH 3 to 81 H 3 7 H CH 3 9 H CH 3 C0C Hc 5 905 H H H H H 2 H CH2C1 H H CH2C1 H H H H H H H CH 2 3 3 H 2 3 3 H CH 2 2 5 3 0 to 95 bp 95 to 100 3 3 CH2C1 CH2Br 3 CH5 3 H bp 2 to 108 H bp 15 97 to 108 H bp 98 to 105 3 Formula II bp H 99 to 105 H to 102 The new compounds of great importance as precursors for plant protection agents and pharmaceutical For example by reaction of compounds of formula with methyl active substances may be prepared which have a good insecticidal action both on biting and sucking insects and outstanding e fectiveness against red spiders and At the same time they have only slight phytotoxicity The action is rapid and For this reason the active substances may be used successfully in plant protection for injurious sucking and biting insects and Diptera and for combatting mites both this and the veterinary In this context emphasis may be placed on the excellent effectiveness of the active stances against of red spiders which are resistant to phosphoric The following examples illustrate the EXAMPLE 1 parts by weight of pyrocatechol is suspended in 100 parts by weight of At 64 parts by weight of vinyl methyl ether which has a temperature of is poured in all at once and then 1 drop of concentrated hydrochloric acid is The whole is heated to about while whereupon the reaction commences and the temperature of the contents of the flask rises to about External coolin with ice may be applied if The whole is kept for half an hour at and then 5 parts by weight df caustic soda solution is The whole is and dried by means of sodium and the solvent is evaporated in a rotary The product is distilled in The yield is 155 parts by The boiling point is to at 168 C H C pyrocatechol bis 1 The reaction described under is repeated but with twice the amount 128 parts by of vinyl methyl 122 parts by weight of a colorless oil is obtained having a boiling point of to at C H C H 1 parts of S0C12 is added to 113 parts by weight of ether and 55 parts by weight of pyrocatechol at and the whole is stirred at this temperature for half an It is then allowed to cool and 2 parts by volume of by weight aqueous caustic soda solution is The product is separated and dried over sodium sulfate and the solvent is There remains 168 parts of the tioned compound having a boiling point of to at EXAMPLE 2 220 parts by weight of pyrocatechol is suspended in 200 parts by weight of After 2 drops of concentrated hydrochloric acid have added 150 parts by weight of ethyl vinyl ether is dripped in The internal temperature is prevented from rising above by external cooling with All of the pyrocatechol has dissolved completion of the 5 parts by weight of caustic soda solution is the whole is allowed to and dried over sodium the solvent is removed and the product is distilled in The yield is almost boiling point to at 1 C H C H Pyrocatechol bis The method of is except that parts by weight of ethyl vinyl ether is used instead of 150 parts by 248 parts by weight of a colorless oil is obtained having a boiling point of to at C H C H 127 parts by weight of pyrocatechol ether and 55 parts by weight of pyrocatechol are reacted and processed as described in Example The yield is 179 parts of the phenol The boiling point is at 1 insufficientOCRQuality

Claims (10)

CLAIMS 23.x..72 1. A pyrocatechol ether of the formula: except for R compounds of Claim 2 where 1 2 R is hydrogen or lower alkyl (C^ to C4) ; R is lower alkyl (C^ to C4) which may be substituted by halogen or is benzyl; R is lower alkyl (C^ to C4), cyeloalkyl (C3 to C^) , phenyl, β-chloroethyl , lower alkenyl (up to C^) , lower alkynyl (up to

1. 2 C^) or lower alkanoyl; or R and R together with the carbon atom whose substituents they are, denote a five-membered or 2 3 six-membered saturated ring, or R and R together with the carbon and oxygen atom whose substituents they are, denote a five-membered or six membered saturated ring 25.3.76 which is optionally substituted with methyl.

2. A pyrocatechol ether of formula (I) in Claim 1 in 1 5 · χ· 73 which R is hydrogen or lower alkyl; R is methyl, ethyl or lower haloalkyl (C± to C4); and R3 is lower alkyl (^ to C3), 3-chloroethyl or acetyl.

3. A pyrocatechol ether as claimed in claim 1 and specified in any of the foregoing Examples, except those claimed in Claims 5 to 8.

4. . 4. A process for the production of a pyrocatechol ether as claimed in claim 1 wherein pyrocatechol is reacted, in the presence of a base, with a vinyl ether of the formula ROR^, where R is a vinyl group which may be substituted by lower alkyl and R^ has the meanings given in claim 1, or with an J-haloether of the for- R1 mula: I ., 43480/3 1 2 where Hal is CI, Br or I and R , R and have the meanings given in claim 1.

5. A process as claimed in claim 4 wherein any bisether obtained having the formula: R1 ■ . l2 R 1 2 · ~*> in which R , R and have the above meanings is reacted with pyrocatechol .

6. o- (1 -methoxyethoxy) -phenol.

7. o-(l-ethoxyethoxy) -phenol.

8. o-(2-methoxyisopropoxy) -phenol.

9. A process as claimed in claim or 5 when carried out substantially as described in any of the foregoing Examples.

10. Pyrocatechol ethers when obtained by the process as claimed in claim 4, 5 or 9· ND:dn