摘要 |
The present invention relates to a process for the preparation of an isochroman-3-one of the formula (I)by reaction of a 1,2-bishalomethylbenzene of the formula (II)in which X is chlorine, bromine or iodine, with carbon monoxide and a compound of the formula (III)at a CO pressure of 0.1 to 50 MPa and a temperature of 20 to 200° C. in the presence or absence of an ionic halide, in the presence of a palladium catalyst and of a dipolar aprotic solvent, with addition of water or without addition of water, where in the formulae (I) and (II) the radicals R1, R2, R3 and R4 independently of one another are: a hydrogen or fluorine atom; an NC or F3C group; an alkyl, alkoxy or acyloxy radical, in each case having 1 to 18 carbon atoms; or a C6-C18-aryloxy, aryl or heteroaryl radical, where 1 to 3 atoms from the group consisting of O, N and/or S are present as heteroatoms;or in which at least two of the radicals R1, R2, R3 and R4 are linked to one another and form at least one aliphatic or aromatic ring having 5 to 18 carbon atoms, and in formula (III) the radicals R5, R6 and R7 are identical or different and are a C1-C18-alkyl, an HOC(=O)-, H3CC(=O)CH2- or (C6-C18-aryl)-CH2- radical or at least two of the radicals R5, R6 and R7 are linked to one another and form at least one aliphatic or aromatic ring having 5 to 18 carbon atoms.
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