Copper-Catalyzed Hydroboration of Enamides with Bis(pinacolato)diboron: Promising Agents with Antimicrobial Activities

Table 1

Influence of the base on the hydroboration reaction^a.

Base (0, 1 equ)	Pka	t	Conv (%)	Ed^c (%)	Yield^b (%)
Ca (OH)2	14	15 min	100	38	100
Ba (OH)2	14	15 min	100	38	100
K3PO4	12	15 min	100	42	100
Li2CO3	10	15 min	100	44	100
Na2CO3	10	15 min	100	44	100
K2CO3	10	15 min	100	44	100
Cs2CO3	10	15 min	100	48	100
Na2HPO4	7	15 min	100	42	100
KH2PO4	2	12 h	0	ND	100

^aReaction conditions: 5 (0.2 mmol), B₂(pin)₂ (1.5 equiv) NHCCuCl (1) (10 mol%), MeOH (1 mL), and r.t. ^bisolated yield. ^cThe Ed (%) was determined by ¹H NMR analysis.