Model Michael addition in heterogeneous environment catalyzed with IIa and IId^a.

Entry	Catalyst	Solvent	Conversionb (isol. yieldc) [%]	eed [%]	syn : antib
1	IIa	neate	51 (36)	78	95 : 5
2	IIa	Neate	34 (17)	72	94 : 6
3	IIa	Neate	37 (20)	70	96 : 4
4	IIa	Neate	32 (18)	69	96 : 4
5	IIa	Neate	35 (21)	69	93 : 7
6	IId	Hexane	37 (21)	80	94 : 6
7	IId	Hexane	21 (13)	80	95 : 5
8	IId	Hexane	20 (11)	89	92 : 8
9	IId	Hexane	22 (13)	81	94 : 6
10	IId	Hexane	19 (12)	79	93 : 7

^aReaction conditions: nitrostyrene 0.25 mmol, cyclohexanone 250 μl, catalyst 0.05 mmol, acetic acid 0.035 mmol, solvent 1 ml, t = 25 °C, reaction time = 72 h.

^bDetermined by ¹H NMR.

^cPurified by column chromatography (hexane : ethyl acetate = 5 : 1).

^dDetermined by chiral HPLC (column YMC Amylose C, mobile phase heptane : IPA = 9 : 1, flow rate 0.7 ml min⁻¹).

^eAdditional 750 μl of cyclohexanone was used instead of the solvent.