Z-Selective Addition of Diaryl Phosphine Oxides to Alkynes via Photoredox Catalysis
作者:Huamin Wang、Yongli Li、Zilu Tang、Shengchun Wang、Heng Zhang、Hengjiang Cong、Aiwen Lei
DOI:10.1021/acscatal.8b02617
日期:2018.11.2
Radical addition to alkynes is known to predominantly yield thermodynamically more stable E-alkenes. Control of stereoselectivity in these reactions, and the isolation of the higher-energy Z-alkenes, remain an important challenge in chemical synthesis. Herein, directsynthesis of Z-alkenylphosphine oxides via visible-light-induced radical addition to alkynes in water is reported. This protocol was
已知向炔烃中自由基加成主要产生热力学上更稳定的E-烯烃。这些反应中立体选择性的控制以及高能Z-烯烃的分离仍然是化学合成中的重要挑战。本文中,报道了通过可见光诱导的自由基加成至水中的炔烃直接合成Z-烯基膦氧化物。该方案对各种末端和内部炔烃均有效,可提供具有高Z-立体选择性的产物。此外,这种转化以克为单位进行了证明。机理研究支持以下结论:(1)通过自由基加成反应。(2)K 2 CO 3的选择因为水性碱对转化至关重要;(3)π–π堆积相互作用极大地提高了Z选择性。
Solovetskaya, L. A.; Sergeev, N. M.; Magdeeva, R. K., Journal of general chemistry of the USSR, 1985, vol. 55, # 5, p. 1072 - 1073
作者:Solovetskaya, L. A.、Sergeev, N. M.、Magdeeva, R. K.、Nifant'ev, E. E.
DOI:——
日期:——
Nifant'ev, E. E.; Solovetskaya, L. A.; Magdeeva, R. K., Journal of general chemistry of the USSR, 1985, vol. 55, p. 2010 - 2015
作者:Nifant'ev, E. E.、Solovetskaya, L. A.、Magdeeva, R. K.
DOI:——
日期:——
Tandem Peterson-Michael Reaction Using a-Silylalkylphosphine Chalcogenides and Horner-Emmons Reaction of in situ Generated a-Carbanions of Its Products
作者:Takayuki Kawashima、Mio Nakamura、Naoki Inamoto
DOI:10.3987/com-96-s49
日期:——
Title tandem reaction was achieved by using alpha-(trimethylsilyl)alkylphosphine chalcogenides and the lithio derivative of 2-hydroxytetrahydropyran. The Horner-Emmons reaction of the tandem products was accomplished to give the corresponding 2-(beta-styryl)tetrahydropyran derivatives by in situ generation and trapping of alpha-lithio derivatives, followed by Warren's method of olefination.
NIFANTEV, EH. E.;SOLOVETSKAYA, L. A.;MAGDEEVA, R. K., ZH. OBSHCH. XIMII, 1985, 55, N 10, 2263-2269
作者:NIFANTEV, EH. E.、SOLOVETSKAYA, L. A.、MAGDEEVA, R. K.