Patent ID: 6166208
Filing Date: 2000-12-26
Classification: C07C,C07D

Abstract:
A process for preparing a quinazolinone of Formula I ##STR133## wherein R.sup.1 is C.sub.1 -C.sub.10 alkyl; C.sub.3 -C.sub.10 alkenyl; C.sub.3 -C.sub.10 cycloalkyl; C.sub.3 -C.sub.10 halocycloalkyl; C.sub.4 -C.sub.10 cycloalkylalkyl; C.sub.4 -C.sub.10 halocycloalkylalkyl; or C.sub.3 -C.sub.10 alkynyl;R.sup.2 is C.sub.1 -C.sub.10 alkyl; C.sub.3 -C.sub.10 alkenyl; C.sub.3 -C.sub.10 cycloalkyl; C.sub.3 -C.sub.10 halocycloalkyl; C.sub.4 -C.sub.10 cycloalkylalkyl; C.sub.4 -C.sub.10 halocycloalkylalkyl; C.sub.4 -C.sub.10 cycloalkyl; C.sub.4 -C.sub.10 halocycloalkyl; or C.sub.3 -C.sub.10 alkynyl; and R.sup.3 and R.sup.4 are each independently hydrogen or halogen;characterized by employing a process sequence comprising:(a) treating a 2-thioquinazolinedione of Formula IIa ##STR134## with phosgene in an inert solvent, at a temperature of from about 50 to 1 20.degree. C., and a pressure of from about 1 to 5 atmospheres, to form a 2-chloro-4(3H)-quinazolinone of Formula IIb (b) treating the 2-chloro-4(3H)-quinazolinone with a metal alkoxide of Formula M.sup.+ (.sup.- OR 2) wherein M is lithium, sodium or potassium, in an inert solvent, at a temperature of from about -20 to 50.degree. C., and a pressure from about 1 to 5 atmospheres.