Patent ID: 6048983
Filing Date: 2000-04-11
Classification: C07C,C07D

Abstract:
A process for the preparation of a compound of structure (I): ##STR8## in which, R.sup.1 is C.sub.1-20 alkyl, C.sub.2-20 alkenyl, C.sub.2-20 alkynyl, or a group of structure: ##STR9## each of which may be substituted by one or two substituents selected independently from C.sub.1-20 alkyl, C.sub.2-20 alkenyl or C.sub.2-20 alkynyl, up to 5 carbon atom(s) of which may optionally be replaced by oxygen atom(s), sulphur atom(s), halogen atom(s), nitrogen atom(s), benzene ring(s), thiophene ring(s), naphthalene ring(s), carbocyclic ring(s) of from 4 to 7 carbon atom(s), carbonyl group(s), carbonyloxy group(s), hydroxy group(s), carboxy group(s), azido group(s) and/or nitro group(s);R.sup.2 is hydrogen or C.sub.1-6 alkyl;R.sup.3 is hydrogen, halogen, hydroxy, nitro, a group of general formula --COOR.sup.6 (wherein R.sup.6 represents hydrogen or C.sub.1-6 alkyl), C.sub.1-6 alkyl, C.sub.1-6 alkoxy or C.sub.1-6 alkylthio;A is a single bond or a vinylene, propenyl-1-ene, butenyl-1-ene, butadienyl-1-ene or ethynylene group optionally being substituted by one, two or three C.sub.1-10 alkyl and/or phenyl group(s); provided that the group formed by R.sup.1 and A provides a double or triple bond adjacent to the carbonyl group of the compound of formula (I);R.sup.4 is OH and R.sup.5 is COCH.sub.3 or R.sup.4 and R.sup.5 together form a group of formula (i): ##STR10## which comprises reaction of a compound of formula (II): ##STR11## in which R.sup.2, R.sup.3, R.sup.4 and R.sup.5 are as defined in formula (I) with a compound of formula (III): ##STR12## in which R.sup.1 and A are as defined in formula (I) and X is halogen or a triflate group, and optionally thereafter,forming a salt or N-oxide.