Table 1.

Optimization of Radical Addition Reaction

entry	Lewis acid (2 equiv)	silicate (equiv)	solvent	time (h)	% conva
1	none	2	DMSO	24	40
2	none	2	DMSO	49	48
3	ZnBr2	1	DMSO	18	27
4	Zn(OTf)2	1	DMSO	18	27
5	ZnBr2	2	DMSO	18	63
6	ZnBr2	4	DMSO	18	64
7	ZnBr2 (3 equiv)	2	DMSO	18	49
8	MgCl2	2	DMSO	18	59
9	MgBr2	2	DMSO	18	54
10	Mg(OTf)2	2	DMSO	18	31
11	ZnBr2	2	DMF	16	28
12	MgCl2	2	DMF	16	44
13	MgCl2	1.2	EtOH	23	10
14	MgCl2	2.6	DMSO	48	86
15	MgCl2	3	DMSO	48	22b
16	MgCl2	3	DMSO	48	68c
17d	MgCl2	3	DMSO	47	88 (60e)
18	MgCl2	2	DMSO	24	73

^aDetermined by ¹H NMR integration.

^b1 mol % of catalyst loading.

^c5 mol % of catalyst loading.

^dConversions in control experiments using conditions of entry 17: Absence of blue LED (0%), absence of 4CzIPN (0%), open to air (67%), replacing silicate with CyBF₃K (59%).

^eIsolated yield.