A new type of organocatalyst for highly stereoselective Michael addition of ketones to nitroolefins on water

(S)-2-((Naphthalen-2-ylsulforly))methyl)pyrrolidine, prepared in three steps from (S)-N-Boc-2-[((4-toluenesulfonyl)oxy)methyl]pyrrolidine in 62% overall yield, was used as a new type of organocatalyst bearing a pyrrolidine and a sulfone moiety. It shows very high catalytic activity toward the direct asymmetric Michael reaction of cyclohexanone and nitroolefins. All the corresponding adducts can be furnished in 90-99% yields and with up to 98% ee and over 99:1 dr oil water ill the presence of this catalyst (15 mol %) without any additive. (C) 2009 Elsevier Ltd. All rights reserved.