Summary: | 碩士 === 國立清華大學 === 化學系 === 99 === This thesis reports the asymmetric tandem reaction using 1,3-dioxolan-4-one 14. At first, Michael reaction of the enolate from 1,3-dioxolan-4-one 14 with methyl crotonate afforded product 20b with two contiguous chiral centers. Compound 20b underwent α-substitution reaction and generated the third chiral center. The first Michael reaction gave a single product in 82% yield, and the second reaction afforded product with high diastereoselectivity(up to 80.4/1.8) in 53-83% yield. Enolate of 1,3-dioxolan-4-one 14 reacted with methyl tiglate and, after the treatment with chiral compound 33 as proton source, afforded single product 31 in 64% yield.
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