Patent ID: 7501520

Claim:
A method of making a compound of Formula Ib: wherein R 4 and R 5 are H, alkyl or aryl, or R 4 is —SiR 20 , R 21 R 22 , wherein R 20 , R 21 and R 22 are each independently alkyl or aryl; R 6 is H, alkyl, aryl or halo; R 7 is H, alkyl or aryl; and X is halo; comprising the steps of: (a) metalating a compound of Formula II: wherein R 2 is H, with lithium tetramethylpiperidide in the presence of a compound of the formula X′SnR 30 R 31 R 32 , wherein X′ is halo and R 30 , R 31 and R 32 are each alkyl or aryl, to form an organometallic intermediate compound of Formula III: and then (b) reacting said organometallic intermediate compound of Formula III with a halogenating agent to produce a compound of Formula Ib.