Tris(3,6-dioxaheptyl)amine: A superior complexing agent for dissolving metal reactions
作者:Ajay K. Bose、Pietro Mangiaracina
DOI:10.1016/s0040-4039(00)95452-2
日期:1987.1
Commercially available tris(3,6-dioxaheptyl)amine (TDA-1) is an effective phase transfer catalyst for reactions with sodium-potassium alloy in tetrahydrofuran. Deoxygenation of acetates, dehalogenation, and hydrolysis of tosylates and mesylates proceed in high yield. The use of a deuterated alcohol during deoxygenation reactions leads to site-specific deuteration.
Circular dichroism and optical rotatory dispersion of some hexahydroindanone derivatives; methyl- and methylene-substituted steroid ketones
作者:M. J. Brienne、A. Heymes、J. Jacques、G. Snatzke、W. Klyne、S. R. Wallis
DOI:10.1039/j39700000423
日期:——
Circulardichroism and opticalrotatorydispersion curves of a number of steroid hexahydroindanones have been measured. The compounds were A-nor-5α-androstan-2-ones and 5α-androstan-16-ones carrying methyl groups in positions adjacent to carbonyl. The curves are discussed in relation to the probable conformations of the cyclopentanone ring. Some data on related αβ-unsaturated ketones are also included
Four sterane hydrocarbons were prepared for comparison with fossil organic biomarkers in geological samples from Oman. 17β-Methylestrane was prepared in six steps (36 % overall yield) from estrone methyl ether. Key steps of this sequence were a Wittig olefination and Birch reduction of the A-ring. 17β-Methylandrostane was obtained in four steps (85 % overall yield) from trans-androsterone by four functional
制备了四种甾烷烃,用于与阿曼地质样品中的化石有机生物标志物进行比较。17β-甲基雌酮是通过六步(36% 的总产率)从雌酮甲基醚中制备的。该序列的关键步骤是 A 环的 Wittig 烯化和 Birch 还原。17β-甲基雄甾烷是通过四个官能团相互转化反应(包括 Wittig 烯化)从反式雄甾酮分四步(总产率为 85%)获得的。17β-甲基-和 2α-甲基-A-nor-5α-雄甾烷(总产率分别为 14% 和 15%)也由反式雄酮制备。关键步骤是三硝酸铊介导的 A 环酮环收缩为 A-nor-2-羧酸。四种合成中的去官能化是通过催化加氢、黄敏龙还原、巴顿脱羧、