122359-42-6Relevant articles and documents
Enantiomerically Pure Building Blocks from Sugars, 9. An Expedient Approach to Pyranoid Ene and Enol Lactones by BF3-Catalyzed Peroxidation of Glycal and Hydroxyglycal Esters
Lichtenthaler, Frieder W.,Roenninger, Stephan,Jarglis, Pan
, p. 1153 - 1162 (2007/10/02)
An effective and convenient one-pot procedure, simply involving treatment with boron trifluoride/3-chloroperbenzoic acid (MCPBA), is detailed for the high-yield acquisition of enantiomerically pure dihydropyran-2-ones from mono- and disaccharide-derived glycal and hydroxyglycal esters.An assessment of the scope of the method is given, a total of 17 examples being ample evidence for its preparative utility and apparent generality.Substantiation of the mechanism presented - BF3-promoted removal of the allylic acyloxy group, seizure by MCPBA of the allylcarboxonium ion generated, and fragmentation of the resulting hex-2-enopyranose 1-(3-chloro)perbenzoates on quenching - is provided by characterization of the perester intermediates.Conducting the reaction of glycal esters at room temperature a glycol-type C-1-C-2 bond cleavage occurs instead with the generation of acylated 4,5-dihydroxypentenals.