Chiral multifunctional thiourea-phosphine catalyzed asymmetric [3 + 2] annulation of Morita-Baylis-Hillman carbonates with maleimides

Beilstein J Org Chem. 2012:8:1098-104. doi: 10.3762/bjoc.8.121. Epub 2012 Jul 16.

Abstract

We have developed a multifunctional thiourea-phosphine catalyzed asymmetric [3 + 2] annulation of Morita-Baylis-Hillman (MBH) carbonates with maleimides, which can efficiently construct functionalized cyclopentenes bearing three contiguous stereocenters in moderate to excellent yields and excellent diastereo- and enantioselectivities. A plausible mechanism has been also proposed on the basis of control experiments and previous literature.

Keywords: Morita–Baylis–Hillman carbonates; asymmetric [3 + 2] annulation; maleimides; multifunctional thiourea-phosphine; organocatalysis.