Synthesis of dipeptide isosteres by cross-metathesis

This work describes the attachment of two amino acid derivatives by olefin cross-metathesis using Grubbs' second generation catalyst. They were connected at the carboxyl termini. In addition, a cyclic dilactam scaffold was used, which reacted with only a fraction of the amino acid derivatives. The remaining fraction coupled directly coupled with no scaffold. This highly trans-selective double attachment resulted in the cross-metathesis of a variety of amino acids in a single reaction.