Table 3.

Formation of amide 10: selected optimization reactions.

entry	conditionsa	yield of 10b	yield of 11b	yield of 15b
1	chloroacetic anhydride (10 equiv)	0	99	0
2	chloroacetic anhydride (10 equiv), NEt3, acetonitrile	0	90	trace
3	chloroacetic anhydride (10 equiv), K2CO3, acetonitrile	0	34	trace
4	chloroacetic anhydride (20 equiv), K2CO3, acetonitrile	0	36	trace
5	chloroacetic anhydride (8 equiv), K2CO3, toluene, water separator	0	trace	96
6	chloroacetic anhydride (8 equiv), Na2CO3, toluene, water separator	0	trace	92
7	chloroacetic anhydride (8 equiv), NaHCO3, toluene, water separator	0	trace	91

^aReaction performed on a 10 mmol scale. ^bIsolated yield.