Patent ID: 7125558

Claim:
A process for preparing a bis-activated polyethylene glycol having the formula: Y-Q-O—(CH 2 —CH 2 —O) n -Q-Y wherein n is an integer between 4 and 800; Y is selected from the group consisting of a halide group, a mesyl group, a tosyl group, an imidazolyl group, an N-hydroxy-succinimidyl group, a phenoxyl group, and a substituted phenoxyl group; and Q is selected from the group consisting of SO 2 , CO(CHR 1 ) t SO 2 , CO—O—(CHR 1 ) t —O—SO 2 , C(O), SO 2 (CHR 1 ) t SO 2 , SO 2 —O—(CHR 1 ) t —O—SO 2 , CO—O—(CHR 1 ) t —CR 2 ═CR 3 —(CHR 4 ) t —O—CO, and SO 2 —O—(CHR 1 ) t —CR 2 ═CR 3 —(CHR 4 ) t —O—SO 2 , wherein t is 1, 2, or 3; and R 1 , R 2 , R 3 and R 4 are independently selected from the group consisting of H, a lower alkyl group, a lower branched alkyl group, an aryl group, and an aralkyl group; the process consisting essentially of reacting under stoichiometric conditions a polyethylene glycol having the formula: H—(O—CH 2 —CH 2 —) n —OH wherein n is an integer between 4 and 800; with an activator having the formula of Y-Q-X; wherein X and Y independently are selected from the group consisting of a halide group, a mesyl group, a tosyl group, an imidazolyl group, an N-hydroxy-succinimidyl group, a phenoxyl group, and a substituted phenoxy group; and Q is selected from the group consisting of SO 2 , CO(CHR 1 ) t SO 2 , CO—O—(CHR 1 ) t —O—SO 2 , C(O), SO 2 (CHR 1 ) t SO 2 , SO 2 —O—(CHR 1 ) t —O—SO 2 , CO—O—(CHR 1 ) t —CR 2 ═CR 3 —(CHR 4 ) t —O—CO, and SO 2 —O—(CHR 1 ) t —CR 2 ═CR 3 —(CHR 4 ) t —O—SO 2 , wherein t is 1, 2, or 3; and R 1 , R 2 , R 3 , and R 4 are independently selected from the group consisting of H, a lower alkyl group, a lower branched alkyl group, an aryl group, and an aralkyl group; in the presence of a solvent and an aromatic nitrogen-containing heterocyclic base having the formula: wherein (NR 5 R 6 ) c is located either in the ortho or para position; R 5 and R 6 are independently selected from the group consisting of a lower straight alkyl group, a lower branched alkyl group, an aryl group, and an aralkyl group; and c is 1 or 2; to produce said bis-activated polyethylene glycol.