Table 1.

Selected examples for optimization.

Entrya)	Deviation from standard conditions	Product 1b b)	Relative ratio of S=X (X = O, NH)a), c)
			S=O	S=NH
1	No deviation from standard condition	98%	98%	trace
2	Fe(acac)2, no L1	59%	58%	trace
3	FeCl2, no L1	50%	49%	trace
4	FeSO4.7H2O, no L1	70%	68%	trace
5	FePc, no L1	95%	94%	trace
6	L5 instead of L1	98%	96%	trace
7	L6 instead of L1	97%	95%	trace
8	L7 instead of L1	55%	17%	39%
9	L10 instead of L1	75%	37%	38%
10	L11 instead of L1	90%	70%	20%
11	Fe(acac)3, no L1	20%	19%	trace
12	H2O	95%	93%	trace
13	CH2Cl2	26%	7%	19%
14	1 equiv of PivONH3OTf	20%	19%	trace
15	No catalyst	22%	13%	7%
16	Under Argon	95%	93%	trace

^a)See SI for further information.

^{b) 1}H NMR yield.

^c)HRMS and GC‐MS