Greatrex, B.Kimber, M.Taylor, D.Fallon, G.Tiekink, E.2007-02-252007-02-252002Journal of Organic Chemistry, 2002; 67(15):5307-53140022-32631520-6904http://hdl.handle.net/2440/4549Copyright © 2002 American Chemical SocietyAddition of highly stabilized ester nucleophiles to 1,2-dioxines affords good to high yields of γ-lactones with high diastereoselectivity. Heterolytic or homolytic cleavage of the 1,2-dioxines under appropriate conditions generates the key reactive cis γ-hydroxy enones, which ultimately afford the observed γ-lactones. Diastereoselectivity is installed as a result of anti 1,4-addition by the ester enolate to the cis enones followed by intramolecular cyclization. The reaction is tolerant of a range of substitution patterns on the 1,2-dioxine while a broad range of esters are also accommodated. In addition to the synthesis of racemic γ-lactones, highly enantioenriched γ-lactones can also be synthesized when chiral cobalt(II) catalysts are employed for the initial homolytic ring-opening of the 1,2-dioxine.en1,2-dioxines as masked cis γ-hydroxy enones and their versatility in the synthesis of highly substituted γ-lactones1,2-dioxines as masked cis gamma-hydroxy enones and their versatility in the synthesis of highly substituted gamma-lactonesJournal article002002000410.1021/jo02004210001769189000322-s2.0-003717849460692Taylor, D. [0000-0002-3302-4610] [0000-0002-4274-3983] [0000-0003-0633-7424]