Remarkable phosphine-effect on the intramolecular aldol reactions of unsaturated 1, 5-diketones: Highly regioselective synthesis of cross-conjugated dienones

RK Thalji, WR Roush

Index: Thalji, Reema K.; Roush, William R. Journal of the American Chemical Society, 2005 , vol. 127, # 48 p. 16778 - 16779

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Citation Number: 49

Abstract

We report a phosphine-mediated intramolecular aldol cyclization of unsaturated diketones that proceeds with extremely high levels of regioselectivity for the cross-conjugated bicyclic dienone products. The sense of regioselectivity observed in this reaction is complementary to that obtained using traditional aldol conditions. Experimental evidence that supports the involvement of a phosphine Michael adduct is described.