This paper describes studies on the feasibility of an asymmetric Favorskii rearrangement of a meso-dihaloketone substrate. In the racemic series, metal amide bases in the presence of amines give poor to reasonable yields of ring-contracted unsaturated cyclopentyl amides, whilst amines in aqueous solvent mixtures afford cyclopentyl amides in good to excellent yields. A range of chiral non-racemic amines are screened, a tiny diastereo-bias is observed and a tentative mechanistic rationale for the diastereoselective process is proposed. © 2009 Elsevier Ltd. All rights reserved.
Tomlin, P. M., Davies, D. J., & Smith, M. D. (2009). Favorskii rearrangement of a highly functionalized meso-dihaloketone. Tetrahedron Asymmetry, 20(6–8), 961–969. https://doi.org/10.1016/j.tetasy.2009.03.020