Patent ID: 8309738

Claim:
A method for preparing a compound comprising contacting a compound of formula (I), wherein R 1 -R 6 are each independently hydrogen, cyano, halo, nitro, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-8 cycloalkyl, heterocyclyl, aryl, or heteroaryl, wherein the alkyl, alkenyl, alkynyl, cycloalkyl, heterocyclyl, aryl, and heteroaryl groups are each optionally substituted with one or more groups which are each independently cyano, halo, nitro, C 1-6 alkyl, C 2-6 alkenyl, C 2-6 alkynyl, C 3-8 cycloalkyl, heterocyclyl, aryl, or heteroaryl; R 7 and R 8 are each independently hydrogen, C 1-6 alkyl, or phenyl, wherein the alkyl and phenyl groups are each optionally substituted with one or more groups which are each independently halo or C 1-6 alkyl; or one or more of (a) R 1 and R 2 taken together with the carbon atoms to which they are bonded; (b) R 2 and R 3 taken together with the carbon atoms to which they are bonded; (c) R 3 and R 4 taken together with the carbon atoms to which they are bonded; and (d) R 5 and R 6 taken together with the carbon atoms to which they are bonded, form a fused C 3-8 cycloalkyl, heterocyclyl, aryl, or heteroaryl ring wherein the fused ring is optionally substituted with one or more groups which are each independently halo or C 1-6 alkyl; with sulfuric acid, phosphoric acid, or trifluorosulfonic acid, under suitable reaction conditions to provide a first intermediate; and contacting the first intermediate with a compound of formula (II), in the presence of an alkali hydroxide, wherein M + is lithium, sodium, potassium, or ammonium; and R 10 is C 1-20 alkyl, C 2-20 alkenyl, C 2-20 alkynyl, C 3-8 cycloalkylC 1-6 alkyl, heterocyclylC 1-6 alkyl, arylC 1-6 alkyl, heteroarylC 1-6 alkyl, C 3-8 cycloalkyl, heterocyclyl, heteroaryl, or aryl, wherein R 10 is optionally substituted with one or more groups which are each independently nitro, cyano, halo, hydroxy, C 1-6 alkoxy, C 1-6 alkyl, or C 1-6 haloalkyl; under suitable reaction conditions to provide a compound of formula (III),