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US 5,221,762 AGranted
Preparation of E-oxime ethers of phenylglyoxylic esters
AssigneeBASF SE
InventorsHorst Wingert, Bernd Wolf, Remy Benoit, Hubert Sauter, Michael Hepp, Wassilios Grammenos, Thomas Kuekenhoehner
Life of this patent
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Abstract
E-oxime ethers of phenylglyoxylic esters of the formula I ##STR1## where X and Y are each halogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy or trifluoromethyl; m is an integer from 0 to 4; n is an integer from 0 to 3; are prepared.
Claims8
A process for preparing E-oxime ethers of phenylglyoxylic esters of the formula I ##STR88## where X and Y are each halogen, C.sub.1 -C.sub.4 -alkyl, C.sub.1 -C.sub.4 -alkoxy or trifluoromethyl;
- m is an integer from 0 to 4;
- n is an integer from 0 to 3;
- which comprises the following steps
- a) converting a phenol of the formula II ##STR89## into the phenolate using a base in the presence of a diluent, b) mixing this phenolate with a lactone of the formula III ##STR90## c) removing the diluent by distillation and reacting the mixture in the melt at from 50.degree. and 250.degree. C., and
- d) dissolving the still liquid melt in water and acidifying, and converting the resulting 2-phenoxymethylbenzoic acid of the formula IV ##STR91## e) in a conventional manner with phosgene or thionyl chloride into the corresponding 2-phenoxymethylbenzoyl chloride of the formula V ##STR92## and f) reacting the 2-phenoxymethylbenzoyl chloride V with an alkali metal or alkaline earth metal cyanide, in the presence or absence of hydrocyanic acid, and
- g) reacting the resulting 2-phenoxymethylbenzoyl cyanide of the formula VI ##STR93## with methanol in the presence of an acid h) and reacting the resulting methyl 2-phenoxymethylglyoxylate of the formula VIIa ##STR94## or an acetal of the formula VIIb ##STR95## or a mixture of compounds VIIa and VIIb with O-methylhydroxylamine or one of its acid addition salts, and treating simultaneously or subsequently with an acid.
3 more elements
A process for preparing arylglyoxylic esters of the formula VIId
- Ar--CO--CO--OCH.sub.3 VIId
- where
- Ar is phenyl or naphthyl, each of which can carry from one to four sustituents selected from the group consisting of halogen, alkyl, haloalkyl, alkoxy, haloalkoxy, alkoxyalkyl, phenyl, phenoxy, benzyloxy, naphthoxy, phenoxyalkyl, benzyloxyalkyl and naphthoxyalkyl, where the last seven substituents can be present only once and can carry from one to three of the following:
- halogen, alkyl, alkoxy, phenyl, phenoxy, plus as many halogen atoms as there are other carbon atoms which can be substituted,
- which comprises
- a) reacting an acyl cyanide of the formula VIb
- Ar--CO--CN VIb
- with hydrogen chloride and tert-butyl methyl ester,
- b) optionally, hydrolyzing any byproduct arylglyoxyl-amide of the formula VIIe from step a)
- Ar--CO--CO--NHR VIIe
- where R is hydrogen or acyl, under acidic conditions in the presence of methanol,
- c) optionally, hydrolyzing any byproduct dimethyl acetal of the arylglyoxylic esters of the formula VIIf ##STR108## from step a).
9 more elements
Dependencies are inferred from the claim text.