Table 1.

entrya	amine borane	yield from amine	R1, R2	R	n	products	ratiob	yield
1	17a	77%	H, H	H	1	34a:35a	1:1	69%c
2	E−17b	79%	H, Me	Me	1	34b:35b	43:1	85%c
3	E−17bd	79%	H, Me	Me	1	34b:35b	38:1d	83%c
4	19a	>90%	H, Bn	H	1	36a:37b	1:3	90%
5	E−19b	>90%	H, Bn	Me	1	36b:37b	13:1	83%
6	E−19b	76%	H, Bn	Me	1	36b:37b	18:1e	79%
7	E−19b	>90%	H. Bn	Me	1	36b:37b	10:1f	79%
8	Z−19b	>90%	H. Bn	Me	1	36b:37b	>20:1	87%
9	E−19c	>90%	H, Bn	Et	1	36c:37c	10:1	82%
10	E−19d	>90%	H, Bn	Ph	1	36d:37d	2:1	82%
11	E-19d(D3)	73%	H, Bn	Ph	1	36d(D1):37d(D1)	3:1	NA
12	Z-21c	77%	(CH2)4	Et	1	38c:39c	>30:1	92%
13	25a	41%	H,H	H	2	40a:41a	1:1.5	35%
14	E-25b	55%	H,H	Me	2	40b:41b	4:1	84%
15	Z-25b	71%	H,H	Me	2	40b:41b	14:1	92%
16	27a	63%	H,Bn	H	2	42a:43a	1:3	71%
17	E−27b	92%	H,Bn	Me	2	42b:43b	4:1	76%
18	Z−27b	83%	H,Bn	Me	2	42b:43b	39:1	80%
19	E−31b	63%	H,H	Me	3	44:45	2:1	95%
20	Z-31b	54%	H,H	Me	3	44:45	2:1	91%
21	Z−33b	83%	H,Bn	Me	3	46:47	1.5:1	63%

^aConditions, 50 mol% I₂/DCM, rt; yields refer to aminoalcohols isolated by chromatogaphy as a mixture of regioisomers after workup with NaOOH.

^bNMR assay.

^cReaction quenched after 30 min.

^dCatalytic activation with 10 mol% I_2.

^eRecrystallized substrate.

^fActivation using TfOH.