Twenty iodo-BCP-amides 2 were prepared by HATU-mediated coupling of iodo-BCP-COOH 1b and amines (Scheme 2). We reasoned that amides would be more resilient than esters during the BCP to BCB rearrangement reaction and subsequent hydrazinolysis. Next, we heated 2q and phthalimide with a variety of bases in sulfolane, a high-boiling aprotic solvent 10 (Table , Entries 1-6). Although DBU appeared to provide BCB 3q in 20% NMR yield, we found that the conjugate base of phthalimide (Table ), afforded modest improvement in yield together with operational simplicity. Other solvents were not found to improve the yield (Table , Entries 8-16). Table . Optimization of iodo-BCP-amide substitution reaction a a 2q (1.0 equiv), phthalimide (1.2 equiv), and base (1.2 equiv) were heated to 100 °C in solvent (0.1 M final concentration) for 4 h unless otherwise noted. b NMR yields using 1,2,4,5-tetramethylbenzene as an internal standard. c Potassium phthalimide used. d 16 h reaction time.