Patent GB-637724-A (GB)
Title: Improvements in or relating to the preparation of beta-aroxy carboxylic acid compounds
IPC: C07C51/09
Filed: 1946-08-29
Abstract: Polymeric compounds are obtained by polymerizing unsaturated alcohol esters of betaaroxy polycarboxylic acids which contain an aroxy radical in a beta position to each of a plurality of carboxyl groups. Allyl esters are mentioned.  The above polycarboxylic acids and esters thereof may be used as plasticizers for resinous materials, e.g. vinyl resins or polyvinyl chloride.  Acids of the formula <FORM:0637724/IV (a)/1> where Ar represents a divalent aromatic radical, e.g. an arylene hydrocarbon radical or a halogenated arylene radical, and A represents an alkylidene radical, and esters thereof, e.g. esters derived from 2-ethylhexanol, ethyleneglycol monobutyl ether, ethylene glycol and ethyl, lauryl and benzyl alcohols, are particularly mentioned.  Specifications 635,347, [Group IV (b)], and 649,028 are referred to.ALSO:Beta-aroxy carboxylic acids are prepared by reacting a b -lactone and a phenol under substantially neutral or alkaline conditions, preferably in an inert medium having a pH less than 7.  The phenol may be dissolved in an aqueous solution of an inorganic base such as an alkali metal hydroxide or ammonium hydroxide, then adding the b -lactone to form a salt of the beta-aroxy carboxylic acid from which the free acid is liberated by the addition of mineral acid.  Any phenol may be used such as phenol itself, cresols, xylenols, o-, m-, and p-hydroxy styrenes, cumerol, naphthols, monohydroxy diphenyls, monohydroxy naphthalenes, monohydroxy anthracenes, monohydroxy di- and triphenyl methanes, polyhydric unsubstituted pyrocatechol, phloroglucinol, pyrogallol, p-tert.-butyl catechol, polyhydroxy diphenyls, naphthalenes and anthracenes, alkylidene bis phenols, substituted phenols analogous to the above phenols and containing substituents such as chloro, bromo, iodo, nitro, oxy, cyano, keto, azo, nitrilo, thio, thiono, sulphonyl, amino, mercapto or carboxyl groups.  Specified phenols are o- and p-chloro, 2 : 4-dichloro-, pentachloro-, 2 : 6-dichloro-4-nitro-, 2 : 4-diiodo-, p-bromo-, m-nitro-, o-methoxy-, p-octyloxy-, 2-methoxy-4-methyl-, o-azo-, p-amino-, m-diethylamino- and o-anilino-phenol, 2 : 4 - dichloro - and 2 - aceto - 1 - naphthol, 1 - nitroso - 2 - naphthol, 1 : 2 - dihydroxy - 4-chloro - and 1 : 4 - dihydroxy - 2 : 3 - dichlorobenzene, 5 - chloro - 2 : 3 - dicyanohydroquinone, 1 : 4 - dihydroxy - 2 : 3 - dichloronaphthalene, pyrogallol monoacetate, 3-chloro-4 : 41 - dihydroxy - and 3 : 5 : 31 : 51 - tetra bromo - 4 : 41 - dihydroxy - diphenyl, 2 : 21-dihydroxy diphenyl ether, bis-(2-hydroxy naphthyl - 1) - sulphide, 4 : 41 - dihydroxydiphenyl disulphide, 4 : 41 - dihydroxydiphenyl sulphoxide, 2 : 5 - dehydroxy - diphenyl sulphone, 4 : 41 - dihydroxy - 3 : 5 : 31 : 51 - tetrachlorodiphenyl methane, bis - (4 - hydroxy - 2 : 6-dimethyl - 3 - methoxyphenyl) - methane, bis-(3 - chloro - 4 - hydroxyphenyl) - dimethyl methane, 4 : 41 - dihydroxy - 3 : 5 : 31 : 51-tetrabromostilbene, 1 : 2 - dihydroxy - anthraquinone, salicylic acid, 4 : 41 - dihydroxy-diphenylamine, 2 : 3 - dihydroxy - terephthalic acid and esters thereof, 3 : 5-dinitro-2 : 4-dihydroxy benzoic acid and esters thereof, phenolphthalein, 1 - phenol - 2 - sulphonic acid, and p-hydroxy- and 2 : 3 : 4-trihydroxy-benzophenone. Specified b -lactones are b -propio-, b -butyro-, b -isobutyro-, b -valero-, b -isovalero, b -n-capro-, a -ethyl-b -propio-, a -isopropyl - b  - propio - a  - butyl - b  - propio-, a -methyl - b - butyro - a  - ethyl - b  - butyro and b  - methyl - b  - valero - lactone, lactones of beta - hydroxy - monocarboxylic acids containing cycloalkyl, aryl and aralkyl substituents such as b -cyclohexyl-b -propio-, b -phenyl-b -propio-, a  - phenyl - b  - propio - and b  - benzyl-b -propiolactone, lactones of unsaturated beta-hydroxy-carboxylic acids, mono-b -lactones of dicarboxylic acids and dilactones of dicarboxylic acids in which at least one of the lactone groups is a b -group, e.g. a -dimethyl-b  - propiolactone - b - carboxylic acid, trimethyl - b  - propiolactone - b  - carboxylic acid, b  : b  - dimethyl - b  - propiolactone - a  - carboxylic acid and trimethyl-b -propiolactone-a -carboxylic acid.  The lactones are of the general formula <FORM:0637724/IV (b)/1> wherein R is hydrogen or a hydrocarbon group free from aliphatic unsaturation.  They may be prepared by the method of Specification 649,028.  R may also represent groups containing elements other than or in addition to carbon and hydrogen such as oxygen, nitrogen, sulphur and halogen whether in unreactive structure such as nitro or etho groups or in groups containing reactive hydrogen such as amino and hydroxy groups, e.g. a - or b -nitrophenyl-b -propiolactone, b  - (o - nitro - m - chlorophenyl)-b  - propiolactone, b  - (o - nitro - m - methoxyphenyl) - b  - propiolactone, a  - hydroxy - b -phenyl - b  - propiolactone and a  - bromo-b ,b  - dimethyl - b  - propiolactone - a  - carboxylic acid.  In examples: b -phenoxy-, b -o-chlorophenoxy-, b  - p - chlorophenoxy -, b  - 2 : 4-dichlorophenoxy, b -, o, m- and p-nitrophenoxy-, b  - (2 - naphthoxy) -, b  - (m - cresoxy) -, and b -(o-methoxy-phenoxy)-propionic acids and bis-(3 - chloro - 4 - b  - carboxyethoxyphenyl)-diphenyl methone are prepared.  The betaaroxy polycarboxylic acids which contain an aroxy radical in the beta position to each of a plurality of carboxyl groups may be esterified by the conventional methods, e.g. by forming esters of the formula <FORM:0637724/IV (b)/2> from an alkylidene bis phenol and beat propiolactone and esterifying, wherein Ar is a divalent aromatic radical, preferably on arylene hydrocarbon radical or a halogenated arylene radical in which the connecting valencies are directly attached to the aromatic ring, A is an alkylidene radical and X is the alcohol radical.  Suitable alcohols from which the esters may be prepared are monohydric alcohols such as allyl ethanol, 2-ethylhexanol, lauryl alcohol, benzyl alcohol or ethylene glycol mono-butyl ether and polyhydric alcohols such as ethylene glycol. 4-Chromanone and its derivatives are obtained by heating beta-aryloxy propionic acids with phosphoric acid or other dehydrating agents. Specification 635,347 is referred to.  The Specification as open to inspection under Sect. 91 refers to the use of an alcohol as a solvent for the reaction between a beta-lactone and a phenol whereby an ester of the resulting beta-aroxy carboxylic acid is obtained. The use of thiophenols in place of phenols for the reaction with beta-lactones is also referred to.  This subject-matter does not appear in the Specification as accepted.ALSO:Synthetic rubber is plasticized with a betaaroxy polycarboxylic acid containing an aroxy radical in the beta position to each of a plurality of carboxyl groups, or esters thereof.  Acids of the formula <FORM:0637724/V/1> where Ar represents a divalent aromatic radical e.g., an arylene hydrocarbon radical or a halogenated arylene radical and A represents an alkylidene radical, and esters thereof are particularly mentioned. Specifications 635,347 and 649,028, [both in Group IV (b)], are referred to.