Azabicycloalkenes as synthetic intermediates--synthesis of azabicyclo[X.3.0]alkane scaffolds

A general method to synthesize functionalized azabicycloX.3.0]alkane scaffolds 5 is reported. Key intermediates are azabicycloalkenes such as 1 and 2, which are acylated with unsaturated carboxylic acids and subsequently submitted to tandem olefin metathesis. The resulting bicyclic heterocycles are versatile intermediates for different dipeptide mimetics and can be used as intermediates for natural products with indolizidine scaffolds or analogues thereof. reaction: see text].