Table 4.

Electronic and steric investigation of phosphoramidites with alkyl and aryl acetylenes.^a

entry		ligand substituent		3a:4ab	yield (%)c	ee (%) 3ad	ee (%) 4ad	3q:4qb	yield (%)c	ee (%) 3qd	ee (%) 4qd
	L	R1	R2
1	T1	Ph		1:7.0	80f	83	94	3.2:1	81f	81	73
2	T2	Ph		1:7.3	87f	89	94	2.4:1	80f	83	70
3	T3	Ph		1:3.3	76f	90	81	5.0:1	78f	80	33
4	T4	Ph		1:2.0	14	-	-	>20:1	5	-	-
5	T5			1:6.5	84	91	95	2.5:1	55	87	76
6	T6			1:2.8	68	87	85	8.3:1	68	83	46
7	T7			1:>20	67	69	84	1:1	31	79	74
8	T8			1:5.6	84	96	97	4.0:1	77	90	74
9	T9			1:1.6	75	94	94	12.5:1	72	82	51
10	B1	H		1:2.2	32f	5	55e	1:1.9	19	14e	67e
11	B2e	Me		1:4.5	50f	45e	8	1:4.2	34	18	59
12	B4	TMS		1:7.1	74	36	45e	1:3.6	53	32e	95e
13	B5	TMS		1:12.5	77	37	55e	1:3.6	51	50e	95e
14	B6	TMS		1:12	82	43	55e	1:3.2	63	47e	92e
15	A1			1:>20	77	41	3e	1:6.2	75	8	91e

^aReaction conditions: 1 (2 equiv), 2a, [Rh(C₂H₄)₂CI]₂ 2.5 mol %, L 5 mol % in PhMe at 110 °C for 16 h.

^b–eSee Table 1.

^fReaction conditions: 1 (2 equiv), 2a, [Rh(C₂H₄)₂CI]₂ 5 mol %, L 10 mol % in PhMe at 110 °C for 16 h.