著者

井原 正隆 川口 明洋 加藤木 守 千尋 正利 福本 圭一郎 亀谷 哲治

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 28 (ISSN:24331856)

巻号頁・発行日

pp.339-346, 1986-09-09 (Released:2017-08-18)

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Synthesis of angularly tricyclopentanoid sesquiterpenes, was investigated via tricyclo[7.3.0.0^<1,5>]dodecane derivatives using intramolecular Diels-Alder reaction or intramolecular double Michael reaction as a key step. (1) Highly Stereoselective Total Synthesis of (±)-3-Oxosilphinene via Intramolecular Diels-Alder Reaction-(E,E)-3-(8-Phenylthio-octa-5,7-dien-2-yl)-2-methyl-2-cyclopenten-1-one (19) was prepared from the bromocyclopentenone (16) in three steps. Cycloaddition of 19 gave only one stereoisomer of the tricyclo[7.3.0.0^<1,5>]dodecene (20) having all correct four contiguous asymmetric centers. The cyclo-adduct (20) was converted into the tricyclo[6.3.0.0^<4,8>]undecane (25) via Wolff rearrangement. According to usual procedures, the ester (25) was then transformed into (±)-3-oxosilphinene (1). (2) Synthetic Study of Pentalenene and Pentalenic Acid via Intramolecular Double Michael Reaction-Barbier reaction of 4,4-dimethyl-2-cyclopenten-1-one (34) followed by oxidation with pyridinium chlorochromate gave the enone (36), which was converted into the bis-enone (33) in four steps. Intramolecular double Michael reaction of 33, carried out by heating with trimethylsilyl chloride, triethylamine, and zinc chloride, gave tricyclo[7.3.0.0^<1,5>]dodecanediones (40), which were subjected to Wolff rearrangement to afford the tricyclo[6.3.0.0^<4,8>]undecanes (41) possessing all carbon skeleton of natural products (4 and 5).

著者

井原 正隆 福本 圭一郎

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.44, no.2, pp.96-108, 1986-02-01 (Released:2009-11-13)

参考文献数

48

被引用文献数

16 17

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This article reviews results on double Michael reaction of Diels-Alder type. The review is recorded in four sections ; (i) intermolecular double Michael reaction, (ii) bicycleannulation, (iii) intramolecular double Michael reaction, and (iv) synthesis of heterocyclic compounds having an angular nitrogen. In all sections, applications to syntheses of natural products are briefly discussed.

著者

井原 正隆 川口 明洋 加藤木 守 千尋 正利 福本 圭一郎 亀谷 哲治

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.28, pp.339-346, 1986

---

Synthesis of angularly tricyclopentanoid sesquiterpenes, was investigated via tricyclo[7.3.0.0^<1,5>]dodecane derivatives using intramolecular Diels-Alder reaction or intramolecular double Michael reaction as a key step. (1) Highly Stereoselective Total Synthesis of (±)-3-Oxosilphinene via Intramolecular Diels-Alder Reaction-(E,E)-3-(8-Phenylthio-octa-5,7-dien-2-yl)-2-methyl-2-cyclopenten-1-one (19) was prepared from the bromocyclopentenone (16) in three steps. Cycloaddition of 19 gave only one stereoisomer of the tricyclo[7.3.0.0^<1,5>]dodecene (20) having all correct four contiguous asymmetric centers. The cyclo-adduct (20) was converted into the tricyclo[6.3.0.0^<4,8>]undecane (25) via Wolff rearrangement. According to usual procedures, the ester (25) was then transformed into (±)-3-oxosilphinene (1). (2) Synthetic Study of Pentalenene and Pentalenic Acid via Intramolecular Double Michael Reaction-Barbier reaction of 4,4-dimethyl-2-cyclopenten-1-one (34) followed by oxidation with pyridinium chlorochromate gave the enone (36), which was converted into the bis-enone (33) in four steps. Intramolecular double Michael reaction of 33, carried out by heating with trimethylsilyl chloride, triethylamine, and zinc chloride, gave tricyclo[7.3.0.0^<1,5>]dodecanediones (40), which were subjected to Wolff rearrangement to afford the tricyclo[6.3.0.0^<4,8>]undecanes (41) possessing all carbon skeleton of natural products (4 and 5).