Zur Kenntnis des Kohlenstoffringes。51. Mitteilung。魏尔特(Weitere Untersuchungen)与布雷德(Grell)的布赖特(Schen Regel)一起。Eine Variante der Robinson 's chen von cyclischenungesättigtenKetonen
摘要:
1. Die durch Umsetzung vonγ-氯-巴豆酰氯[1,3-Dichlor-buten-(2)] mit Natrium-cyclanon-(2)-carbonsäure-(1)-esterer erhaltenen Verbindungen IV gehen durch Behandlung mit konz 。Schwefelsäure在β-Keto-carbonsäureesterüber的研究中,被任命为VIIIa级(n = 6,7)或VIIa级(n = 8,13)。
Synthesis of (±)-Gymnomitrol. Mn(OAc)<sub>3</sub>-Initiated Free-Radical Cyclization of Alkynyl Ketones
作者:Steven V. O'Neil、Cheri A. Quickley、Barry B. Snider
DOI:10.1021/jo9622338
日期:1997.4.1
Mn(OAc)(3)-initiated cyclization of alkynyl ketones in 9-19:1 EtOH/HOAc at 90 degrees C is a useful cyclization procedure in favorable cases. Cyclization of (trimethylsilyl)alkynyl ketone 4e provides 62% of silylalkenes 26 and 27 in the key reaction of a seven-step (16% overall yield) synthesis of gymnomitrol (1) from readily available ketone 23. 9alpha-Hydroxygymnomitryl acetate (2) and 9-oxogymnomitryl
Bicyclo[m.n.1]alkenone frameworks possessing quaternary carbon centers adjacent to a bridged ketone are frequently found in bioactive natural products. Although several methods have been developed to construct such frameworks, most of them are specific to a particular scaffold. Herein, we report a mild and highly efficient method to generate carbon-bridged frameworks of various sizes using phosphino gold(I) catalysts.