Patent ID: 7442759

Claim:
A method of forming a water-soluble polymer having formula I: wherein R 1 and R 2 are independently —H, -alkylCO 2 A, —(CH 2 ) n -aryl-(CH 2 ) n CO 2 A, —(CH 2 ) n -heterocycle-(CH 2 ) n CO 2 A-, or —(CH 2 ) n -cycloalkyl-(CH 2 ) n CO 2 A, where n is an integer from 0 to about 200, and A is an alkali metal cation; with the proviso that only one of R 1 and R 2 can be —H; comprising: (a) combining a zerovalent highly reactive zinc species with an ester of an R 1 ,R 2 thiophene having at least two stable leaving groups to form a zinc derivative reagent; (b) adding a catalyst to polymerize the zinc derivative reagent to provide a polymer; and (c) adding an alkali metal base to form an alkali metal salt of the polymer.