Table 3. Radical Bromination of 9a/b for the Synthesis of Bromide 10a/b^a.

reactant	radical initiator	monobromo product (LCAP)	dibromo product (LCAP)
9a	AIBN	10a: 90%b	10a′: <5%
9b	AIBN	10b: 85%c	10b′: 15%
9a	BPO	10a: 82%b	10a′: <5%
9b	BPO	10b: 50%c	10b′: 30%
9b	incandescent light	10b: 80%c	10b′: 10%

^aAll reactions were performed with 9a or 9b (1 g, 1 equiv), NBS (1.1 equiv), initiator (0.1 equiv), or incandescent light at 80 °C in acetonitrile for 8 h.

^bLCAP of the crude residue without trituration.

^cLCAP of the product triturated from water.