Non-Catalyzed Thermal Reactions of Acylquinones with Allylstannanes
作者:Kazuhiro Maruyama、Yoshihiro Matano
DOI:10.1246/bcsj.62.3877
日期:1989.12
Thermal reactions of acylquinones with allylstannanes in benzene afforded several kinds of product after column chromatography on silica gel; acyl allyl quinones, acyl allyl epoxy quinones, cyclopentanoid compounds including stannyl moiety, allyl hydroxy quinones, acyl hydroquinones, and acyl allyl hydroquinones. The main product comprises cyclopentanoid compounds, which are novel [2+3] cyclo adducts with 1,2-migration of trialkylstannyl moiety. Spectroscopic examinations (1H NMR and Vis-UV) enabled us to confirm the reaction pathways that four types of precursors were initially generated via polarized tight pair and inverted to isolated products during purification by column chromatography. Similar reactions in acetonitrile showed a remarkable difference in the reactivity, that is, acyl allyl quinones and the corresponding hydroquinones are obtained, but the [2+3] cyclo adducts are not produced at all. From 1H NMR examination, it was confirmed that three types of precursor are generated via solvent separated ion pairs at the initial stage. The rather strong reactivity of acylquinones towards allylstannanes will be due to electron withdrawing ability of acyl group.
A regioselective annulation to naphthalene ring systems from dimethyl phthalide-3-phosphonates and electron-deficient olefins is described.
描述了一种从二甲基苯二酸酯-3-膦酸酯和电子缺乏的烯烃中选择性合成萘环体系的区域选择性环化反应。
An abnormal fries rearrangement induced by a -methoxyl group in monoacetates of naphthohydroquinones.
作者:Trevor A. Chorn、Robin G.F. Giles、Ivan R. Green、Victor I. Hugo、Peter R.K. Mitchell
DOI:10.1016/s0040-4039(00)87597-8
日期:1982.1
The acetyl group of two 1-acetoxy-4-hydroxy-5-methoxynaphthalenes migrates to C-3 on treatment with borontrifluoride etherate.
在用三氟化硼醚化物处理时,两个1-乙酰氧基-4-羟基-5-甲氧基萘的乙酰基迁移到C-3。
Synthesis of deoxyfrenolicin and nanaomycin A
作者:George A. Kraus、Maria Teresa Molina、John A. Walling
DOI:10.1021/jo00383a018
日期:1987.4
A General Approach to Angucyclines: Synthesis of Hatomarubigin A, Rubiginone B2, Antibiotic X-1488E, 6-Hydroxytetrangulol, and Tetrangulol
作者:Kathlyn A Parker、Qing-jie Ding
DOI:10.1016/s0040-4020(00)00869-3
日期:2000.12
Hatomarubigin A was prepared in 41% yield in a single procedure from acyl naphthoquinone 15 and 5-methylcyclohexane-1,3-dione (16). The net reaction consists of Michael addition to an acyl quinone followed by intramolecular aldol condensation. Hatomarubigin A then served as a common intermediate in syntheses of the angucyclinone antibiotics rubiginone B2, antibiotic X-1488E, 6-hydroxy-tetrangulol, and tetrangulol. (C) 2000 Elsevier Science Ltd. All rights reserved.