PROCESS FOR PREPARING 2-(2-,4- DIFLUOROPHENYL)-2- PROPENYL MALONIC ACID ESTER INTERMEDIATES FOR THE SYNTHESIS OF ANTIFUNGAL COMPOUNDS

摘要

A process for preparing compounds of the formula wherein R is C1-C6 alkyl, comprising heating a mixture of a difluorobenzene derivative of the formula wherein A is Br, I, -OS(O)2R2, or -OP(=O)(OR3)2, and wherein R2 is F, CF3, C1-C6 alkyl, aryl or substituted aryl, and R3 is C1-C6 alkyl, with allene, a dialkyl malonate of the formula CH2(CO2R)2, wherein R is C1-C6 alkyl, and a base, in a polar organic solvent in the presence of a palladium (II) catalyst, in a sealed vessel and the excess pressure within the vessel is 6.9 to 69 Pa (1 to 10 psig). 458 כ" ג בתמוז התש" ס - July 26, 2000