Asymmetric synthesis of cis-hydrindanediones by diels-aider reaction of cyclopentenones bearing a 3-sulfonyl-1,3-oxazolidine ring as chiral auxilliary - Hoffmann, H.; Bolte, M.; Berger, B.; Hoppe, D. (Elsevier)
The Diels-Alder reaction of enantiomerically pure 2- and 5-(1,3-oxazolidin-2-yl)-2-cyclopentenones 8 or 14 and 2-(trimethylsilyloxy)-1,3-butadiene 9 under Lewis-acid catalysis yields (after hydrolysis) protected 3,7-dioxohydrindane-carbaldehydes 11 or 16, respectively.
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Keywords: V