Recent developments in allene-based synthetic methods.

Presented is a review of the advances in synthetic methodology that make use of the allene functional group, with emphasis on catalytic asymmetric transformations and new mechanistic insights. The review covers the period from January 2007 to May 2008 and focuses on intra- and intermolecular cycloaddition, carbocycle cycloisomerization, heterocycle synthesis, epoxidation, addition and miscellaneous transformations. A brief discussion of allenes as transition metal ligands, the use of allenes in total synthesis and potential medicinal agents that contain the allene functionality is also presented.