Table 1.

Optimization of the photochemical chemodivergent reaction^a

Entry	Catalyst	Solvent	Time	3a (%)c	4a (%)c
1	PTH1	Toluene	1 h	38	2
2	PTH2	Toluene	30 min	89 (86)d	7
3	PTH3	Toluene	20 min	68	21
4	PTH4	Toluene	20 min	70	22
5e	fac-Ir(ppy)3	Toluene	6 h	67	8
6	PTH2	CH3CN	45 min	73	6
7	PTH2	DMF	1 h	38	2
8	PTH2	DMSO	1 h	35	2
9	PTH2	1,2-DCE	30 min	76	5
10	PTH4	Toluene	24 h	3	81 (79)d
11	PTH3	Toluene	24 h	4	76
12	PTH2	Toluene	24 h	82	11
13e	fac-Ir(ppy)3	Toluene	24 h	61	12
14	-	Toluene	30 min	2	0
15	-	Toluene	24 h	4	0
16 f	PTH2	Toluene	30 min	0	0
17 g	PTH2	Toluene	30 min	78	5
18 h	PTH2	Toluene	24 h	3	0
19 h	-	Toluene	24 h	3	0

^aConditions: 1a (0.4 mmol), 2a (0.2 mmol), photo-catalyst (5 mol%), solvent (2 mL), degassed condition, irradiation with LEDs light (λ_max = 390 nm) with 100% intensity at 30–35 °C; after completion of photo-reaction, 1 equivalent AlCl₃ (0.2 mmol) was added at 0 °C and stirred for 1 h; ^bAlCl₃ is necessary only facilitate S-cyclization; ^cCrude ¹H NMR yield (%) using 1,1,2,2-tetrachloroethane as internal standard; ^dIsolated yield; ^e1 mol% catalyst loading, irradiation with LEDs light (λ_max = 450 nm); ^fReactions performed in dark; ^gReactions performed in open air; ^hReactions performed at 60 °C.