著者

高野 誠一 小笠原 国郎

出版者

The Society of Synthetic Organic Chemistry, Japan

雑誌

有機合成化学協会誌 (ISSN:00379980)

巻号頁・発行日

vol.40, no.11, pp.1037-1050, 1982-11-01 (Released:2010-01-22)

参考文献数

70

被引用文献数

9 12

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Utility of a chiral glycerin derivative [(S) -1] as a versatile substrate for the enantioselective syntheses of natural products is described. The glycerin derivative [(S) -1] is converted into both enantiomers of the chiral γ-butyrolactone (3) which are in turn transformed to a -monosubstituted lactones (31) and α, α -disubstituted lactones (34) by stereoselective alkylation under kinetic conditions. Inversion of the α center of the monoalkylated lactone 31 is simply achieved by brief exposure of the enolate (32) derived from 31 to saturated aqueous sodium sulfate solution to give (33). α-Aryllactone derivatives (28) which cannot be obtained from the lactone substrate (3) are efficiently prepared from the epoxide (2) obtained from the glycerin derivative (1) and an appropriate phenylacetonitrile.Using the lactone intermediates thus obtained, a dozen of optically active compounds ranging from monoterpenes and alkaloids to a β-lactam derivative illustrated in Fig. 1 are synthesized enantioselectively.

著者

高野 誠一 畑山 範 高橋 召 高橋 洋子 岩田 裕光 宍戸 宏造 小笠原 国郎

出版者

天然有機化合物討論会実行委員会

雑誌

天然有機化合物討論会講演要旨集

巻号頁・発行日

vol.21, pp.50-57, 1978

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A new synthetic approach to the alkaloids related to emetine (3) and quinine(5) from norbornylene(1) is described. Norbornylene(1) was transformed into (±)-norcamphor(2) which was oxidized to the bicyclic lactone(8) by Baeyer-Villiger oxidation then alkylated with ethyl bromide and allyl bromide in a stereospecific fashion to give (9) and (29), respectively. The former lactone(9) was converted into the emetine precursor(21) and protoemetinol(4) both in dl form via the α-diketone monothioketal (13). The latter lactone(29) was converted into the homomeroquinene equivalent(37) via the α-diketone monothioketal(32) which was then transformed into dl-meroquinene aldehyde(6) via the olefin formation through the phenylselenide(41). Since norbornylene(1) has been converted into a chiral norcamphor(2), the present method would be applicable to the synthesis of the above alkaloids together with various indole alkaloids in a chiral form.