PROCESSES AND INTERMEDIATES FOR PREPARING 2-FLUOROTHIOPHENE DERIVATIVES

摘要

A process for the preparation of the compound of formula (I) wherein R<1> is OH, which comprises the steps of a) treating the compound of the formula (III) with an inorganic fluoride, of the formula M<2>F wherein M<2> is an alkali metal cation, at an elevated temperature in the presence of a compound of the formula R<4>P<+>Z<-> and a compound of the formula R<5>vic (COW)2 wherein R<4> and R<5> are each selected from optionally substituted (C6-C10)aryl and optionally substituted (C1-C6)alkyl, and W is halo; to form the compound of formula (IV); and b) i) treating the compound of formula (IV) with an aqueous solution of a base, of the formula MOH, wherein M is an alkali metal cation, and ii) treating the product of step i) with a mineral acid. A compound of formula (A) wherein R<1> is selected from the group consisting of halo, R<7>O, R<7>COO and N(R<8>)2 wherein R<7> is (C1-C6)alkyl or (C6-C10)aryl and each R<8> is selected from hydrogen and R<7> with the proviso that R<7> is not methyl when R<1> is R<7>O.