Patent ID: 6124500
Filing Date: 2000-09-26
Classification: C07C

Abstract:
A process for the preparation of a compound of formula (VII) comprising the steps of(i) reacting a compound of formula (I) with an alkali or alkaline earth alkoxide, alkali or alkaline earth aroxide, alkali or alkaline earth arylalkoxide, or alkali or alkaline earth heteroarylalkoxide, optionally in the presence of a catalyst comprising copper, to form a compound of formula (IIa) ##STR31## (ii) reacting a compound of formula (IIa) with magnesium metal using anhydrous conditions to form an intermediate compound of formula (IIb) ##STR32## (iii) reacting the intermediate compound of formula (IIb) with phosgene to form a compound of formula (VII) ##STR33## wherein each X is independently chloro, bromo or iodo;R is a hydrogen atom, (C.sub.1 -C.sub.6)alkyl, aryl, aryl(C.sub.1 -C.sub.2)alkyl, heteroaryl or heteroaryl(C.sub.1 -C.sub.2)alkyl; or a (C.sub.1 -C.sub.6)alkyl, aryl, aryl(C.sub.1 -C.sub.2)alkyl, heteroaryl or heteroaryl(C.sub.1 -C.sub.2)alkyl substituted with from one to three substituents independently selected from (C.sub.1 -C.sub.3)alkyl and (C.sub.1 -C.sub.3)alkoxy;R.sup.1 is CHR.sup.2 R.sup.3, aryl, aryl(C.sub.1 -C.sub.2)alkyl or heteroaryl(C.sub.1 -C.sub.2)alkyl; or aryl, aryl(C.sub.1 -C.sub.2)alkyl or heteroaryl(C.sub.1 -C.sub.2)alkyl substituted with from one to three substituents independently selected from (C.sub.1 -C.sub.3)alkyl and (C.sub.1 -C.sub.3)alkoxy; andR.sup.2 and R.sup.3 are each independently a hydrogen atom, (C.sub.1 -C.sub.5)alkyl or (C.sub.1 -C.sub.3)alkyl substituted with (C.sub.1 -C.sub.2)alkoxy.