(η6-Arene)ruthenium half-sandwich complexes are highly active and stereoselective catalysts in the enantioselective desymmetrization of 2-n- butyl-4,7-dihydro-1,3-dioxepin to give 2-n-butyl-4,5-dihydro-1,3-dioxepin. Enantioselectivities up to 61% ee were achieved. The temperature and solvent dependence of the catalysis as well as the activation of the catalyst were investigated.
Brunner, H., & Prommesberger, M. (1998). Asymmetric catalysis. Part 127: Enantioselective desymmetrization of 2- n-butyl-4,7-dihydro-1,3-dioxepin with (η6-arene)ruthenium(II) half-sandwich complexes. Tetrahedron Asymmetry, 9(18), 3231–3239. https://doi.org/10.1016/S0957-4166(98)00329-2