Table 3.

Screen of Additional Phenol Substituents in the Boroxainte Core with Ligand L-8.^a

entry	ligand	amine	phenol/alcohol	catalyst	time (h)	% yield 3ab	erc
1	L-4	A-5	P-11	LAP 4-5-11	38	71	61 : 39
2	L-4	A-5	P-36	LAP 4-5-36	42	90	71 : 29
3	L-8	A-5	P-11	LAP 8-5-11	41	72	33 : 67d
4	L-8	A-5	P-26	LAP 8-5-26	39	94	83 : 17
5	L-8	A-5	P-28	LAP 8-5-28	39	72	68 : 32
6	L-8	A-5	P-36	LAP 8-5-36	39	92	87 : 13
7	L-8	A-5	P-36	LAP 8-5-36	39	86	86 : 14e
8	L-8	A-5	P-36	LAP 8-5-36	39	75	84 : 16f
9	L-8	A-12	P-36	LAP 8-12-36	39	65	61 : 39
10	L-6	A-5	P-36	LAP 8-5-36	41	53	32 : 68d
11	L-8	A-5	P-39	LAP 8-5-39	38	95	82 : 18
12	L-8	A-5	P-44	LAP 8-5-44	38	76	59 : 41
13	L-8	A-5	P-47	LAP 8-5-47	38	91	10 : 90d,g,h
14	L-8	A-7	P-47	LAP 8-5-47	24	91	12 : 88d
15	L-8	A-8	P-47	LAP 8-5-47	24	85	10 : 90d
16	L-8	A-9	P-47	LAP 8-5-47	24	80	12 : 88d
17	L-8	A-10	P-47	LAP 8-5-47	24	79	13 : 87d
18	L-8	A-11	P-47	LAP 8-5-47	24	22	27: 73d

^aUnless otherwise specified, all reactions were carried out at 0.2 M in 1 (0.25 mmol) in mesitylene with 2.0 equiv amine and 1.5 equiv of 2 at rt for the indicated time with 20 mol% of the catalyst. Entries 14-18 were carried out in the presence of 4Å molecular sieves. The catalyst was prepared according to the procedure in Table 1 with the (S)-ligand unless otherwise specified. Ligand (S)-L-8 was 97% ee and (R)-L-8, (S)-L-4 and (R)-L-6 were >99% ee.

^bIsolated yield after chromatography on silica gel.

^cDetermined by HPLC.

^dCatalyst generated from (R)-ligand.

^eReaction with 1.2 equiv amine.

^fReaction with 1.02 equiv amine.

^gThe er was 89:11 when (S)-L-8 was 97% ee.

^hThe yield was 86% after 24 h.