Catalytic Z-selective cross-metathesis in complex molecule synthesis: a convergent stereoselective route to disorazole C1

C–H functionalization of terminal alkynes towards stereospecific synthesis of (E) or (Z) 2-methylthio-1,4-ene-diones

An efficient metal free self-sorting tandem protocol for stereospecific synthesis of (E) or (Z) 2-methylthio-1,4-ene-diones has been developed.

Preparation of macrocyclic Z-enoates and (E,Z)- or (Z,E)-dienoates through catalytic stereoselective ring-closing metathesis

The first examples of catalyst-controlled stereoselective macrocyclic ring-closing metathesis reactions that generate Z-enoates as well as (E,Z)- or (Z,E)-dienoates are disclosed. Reactions promoted by 3.0-10 mol % of a Mo-based monoaryloxide pyrrolide complex proceed to completion within 2-6 h at room temperature. The desired macrocycles are formed in 79:21 to >98:2 Z/E selectivity; stereoisomerically pure products can be obtained in 43-75% yield after chromatography. Utility is demonstrated by application to a concise formal synthesis of the natural product (+)-aspicilin.