Table 1.

Catalytic Asymmetric Aldol Reaction of Azlactone 6a and aldehyde 7a^a

Entry	Catalyst	Solvent	Temp(°C)	Time	Conv. (%)c	ee (%)c, d	antilsync
1	1	CHCI3 (2 M)	−20	15 h	>95	29/22	43.5/56.5
2	2	CHCI3 (2 M)	−20	15 h	93	43/12	40.5/59.5
3	3a	CHCI3 (2 M)	−20	15 h	>95	57/25	81/19
4	3b	CHCI3 (2 M)	−20	15 h	>95	51/19	73/27
5	3c	CHCI3 (2 M)	−20	15 h	92	−7/18	71/29
6	3d	CHCI3 (2 M)	−20	15 h	>95	75/13	88/12
7	3e	CHCI3 (2 M)	−20	15 h	>95	−73/−16	90/10
8	4	CHCI3 (2 M)	−20	15 h	91	−64/−6	82/18
9	5	CHCI3 (2 M)	−20	15 h	>95	−71/22	66/34
10	3d	CHCI3 (0.5 M)	−20	34 h	95	86/−11	91/9
11	3d	CH2CI2 (0.5 M)	−20	34 h	93	86/−39	93.5/6.5
12	3d	PhCH3 (0.5 M)	−20	34 h	80	48/−28	80/20
13	3d	THF (0.5 M)	−20	34 h	>95	50/−28	79.5/20.5
14	3d	Et2O (0.5 M)	−20	34 h	>95	53/−28	83/17
15	3d	CH3CN (0.5 M)	−20	34 h	>95	72/−18	88/12
16e, f	3d	CH2CI2 (0.1 M)	−50	88 h	>95 (92)b	94/ND	97.5/2.5

^aReactions were carried out with 0.1 mmol of 6a and 0.15 mmol of 7a.

^bIsolated yield.

^cDetermined by chiral HPLC analysis.

^dee (antilsyn).

^e10 mg of 4Å molecular sieves were added.

^f15 mol% 3d