GB445263A - Manufacture of trichloromethyloxyaryl carbinols and of oxy-acids and oxy-aldehydes therefrom - Google Patents

Abstract

Trichloromethyloxyarylcarbinols, oxyarylglycollic acids and aromatic oxyaldehydes are manufactured by condensing an oxyaryl compound with chloral or chloral hydrate at a raised temperature in the presence of an alkaline reacting salt of a non-volatile acid or an alkali salt of a phenol or phenol derivative, and, if desired, subjecting the product to saponification, or to saponification and oxidation simultaneously or successively. The saponification is advantageously conducted in the presence of an agent which binds hydrogen chloride, e.g. calcium carbonate, whilst the oxidation may be effected by means of oxygen or gases containing oxygen, if desired in the presence of a small proportion of a heavy metal compound capable of undergoing reduction, e.g. a cupric compound, and if desired under pressure. In examples: (1) phenol and chloral hydrate are melted together with the addition of anhydrous secondary sodium phosphate, to produce trichloromethyl-4-oxyphenylcarbinol, which is boiled with water to yield 4-oxyphenylglycollic acid; (2) p-cresol and chloral are melted together with anhydrous tertiary sodium phosphate, to produce trichloromethyl-3-oxy-6-methylphenylcarbinol; (3) molten chloral hydrate is added to a mixture of molten guaiacol and anhydrous sodium guaiacolate, and the product is boiled with water with the addition of prepared chalk and, if desired, copper sulphate, while passing air through the mixture, yielding vanillin; (4) pyrocatechol and chloral are reacted at 70--75 DEG C. in the presence of anhydrous molten borax, producing trichloromethyl-3 : 4-dioxyphenylcarbinol; (5) chloral is added to a mixture of o-chlorophenol and anhydrous sodium o-chlorophenolate, yielding trichloromethyl - 3 - chloro - 4- oxyphenylcarbinol. The potassium salts corresponding to the sodium salts used in (1), (2) and (4) are also specified as condensing agents. Specifications 219,676, [Class 2 (iii)], and 344,675 are referred to. The Specification as open to inspection under Sect. 91 comprises also the reaction of halogen substitution products of phenols with chloral or chloral hydrate in the cold in the presence of anhydrous potassium carbonate. In examples: (a) o-chlorophenol yields trichloromethyl - 3 - chloro - 4 - oxyphenylcarbinol which is saponified with caustic soda and oxidized by adding cupric chloride and passing in oxygen under pressure, producing 3-chloro-4-oxybenzaldehyde; (b) p-chlorophenol is similarly converted to 5 - chloro - 2 - oxybenzaldehyde. Reference is also made to the oxidation of the product of (1) above to 4-oxybenzaldehyde, the saponification and oxidation of the product of (2) to 5-oxy-2-methylbenzaldehyde, and the saponification and oxidation of the product of (4) to protocatechuic aldehyde. Naphthols are additionally referred to as starting materials. This subject-matter does not appear in the Specification as accepted.