Preparation of beta-ketoesters useful in preparing quinolone antibiotics
申请人:Pfizer Inc.
公开号:US05380860A1
公开(公告)日:1995-01-10
A method for preparing a compound of the formula ##STR1## wherein Q is C--H or N; R.sup.1 is C.sub.1-C.sub.4 alkyl, benzyl or p-nitrobenzyl and X and Y are independently selected from fluoro and chloro comprising reacting a compound of the formula ##STR2## wherein Q is >C--H or N; X and Y are independently selected from fluoro and chloro; and Z is fluoro, chloro, 1-imidazolyl or substituted 1-imidazolyl, wherein the 1-imidazolyl group is substituted with one or two substituents independently selected from C.sub.1 to C.sub.4 alkyl, with a compound of the formula [M.sup.n+ ].sub.p [V.sup.p- ].sub.n wherein M is an alkaline earth metal, Cu or Mn, n is 2, V.sup.p-, wherein p is 1 or 2, is an anion of the formula ##STR3## or a dianion of the formula ##STR4## and R.sup.1 is C.sub.1 to C.sub.6 alkyl or paranitrobenzyl, with the proviso that when Z is 1-imidazolyl or substituted 1-imidazole, M is magnesium, copper or manganese and with the proviso that when Z is fluoro, chloro or bromo, V.sup.p- is a dianion of the formula V(b).