Reaction parameters optimization for borylation of 4-chlorotoluene^a.

Entry	Solvent	Base	Yieldb (%)
1	Dioxane	KOAc	17
2	Toluene	KOAc	38
3	THF	KOAc	24
4	Et3N	—	Tracec
5	t-BuOH	KOAc	19
6	EtOH	KOAc	82
7	EtOH	K2CO3	72
8	EtOH	Cs2CO3	51
9	EtOH	CsOAc	34
10	EtOH	K3PO4	50
11	EtOH	K3PO4·7H2O	98
12	EtOH	K3PO4·7H2O	98d, 64e

^aReaction conditions: 1a (1.0 equiv.), B₂pin₂ (2.0 equiv.), XPhos-Pd-G2 (2 mol%), XPhos (4 mol%), base (3.0 equiv.), solvent (0.5 M), 30 min.

^bIsolated yield.

^cEt₃N as solvent.

^dB₂pin₂ (1.2 equiv.), XPhos-Pd-G2 (0.5 mol%), XPhos (0.25 mol%).

^eXPhos-Pd-G2 (0.5 mol%) was used without XPhos.