Synthesis of (+)-Yohimbine

Significance

A very concise synthesis of (+)-yohimbine features creation of the single stereogenic center at C3 in tetrahydro-β-carboline D via an organocatalytic asymmetric Pictet-Spengler reaction. This stereogenic center then controls the simultaneous formation of rings D and E as well as four contiguous stereogenic centers by an intramolecular Diels-Alder annulation (G → I).