多金属氧酸盐(POM)通常使用“自下而上”的合成程序进行制备。拆卸预成型的POM单元以生成新的合成中间体的另一种“自上而下”的方法是有前途的,但相对而言却未得到充分利用。在本文中,提供了自上而下方法的基本原理,证明了该方法可以生成从简单的自下而上的装配基本上无法获得的化合物。我们通过合成10种新的具有通式[TBA] 2 [Mo VI 10 Co II 6 O 30(R p PO 3)6(R c POO)的混合金属混合化合物来证明这一原理。2(L) x(H 2 O) 6 ](TBA =四丁基铵,R p =膦酸酯部分,R c =羧酸酯部分,L =吡啶基配体, x = 2-4),包括基于一维多金属氧酸盐的配位聚合物。我们建议这些结构是从{Mo x O 3 x -1 }片段生成的,这些片段无法单独从下而上的程序集访问。POM簇由三类不同的有机配体(有机膦酸酯,羧酸酯和吡啶基配体)稳定化,它们各自可
The invention of radical reactions. Part 39. The reaction of white phosphorus with carbon-centered radicals. An improved procedure for the synthesis of phosphonic acids and further mechanistic insights
作者:Derek H.R Barton、Richard A Vonder Embse
DOI:10.1016/s0040-4020(98)00729-7
日期:1998.10
long radical chain reaction with carbon radicals derived from Barton PTOC esters. The reaction is initiated by traces of oxygen and strongly inhibited by TEMPO. From the duration of the induction period the chain length can be measured as approximately one million. Each P4 molecule can add up to two carbon radicals. Oxidation of the adducts provides a convenient synthesis of phosphonic acids in high
在氩气下的四氢呋喃中的白磷在长自由基链反应中与衍生自Barton PTOC酯的碳自由基反应。反应由微量氧气引发,并受到TEMPO的强烈抑制。从诱导期的持续时间来看,链长可以测量为大约一百万。每个P 4分子最多可以添加两个碳原子团。加合物的氧化提供了高产率的膦酸的方便合成。在0°C下使用H 2 O 2氧化为合适的次膦酸的速度很快。对于敏感的天然产物,最好在室温下用过量的SO 2进一步转化为膦酸。这样,即使是亚油酸也可以高收率地转化为相应的膦酸,而不会对跳过的二烯单元产生任何攻击。TEMPO还因在暴露于氧气时稳定溶液中的白磷而著称。同样,普通的膦(如三丁基膦)也可以通过少量TEMPO稳定。
Elemental white phosphorus as a radical trap: a new and general route to phosphonic acids
作者:Derek H. R. Barton、Jieping Zhu
DOI:10.1021/ja00058a082
日期:1993.3
for carbon radicals generated by white light photolysis of Barton PTOC esters using CH2Cl2-CS2 as solvent at 0 Deg under dry argon. Removal of the solvent mixt. and oxidn. with H2O2 in 1,2-dimethoxyethane provides an efficient new synthesis of phosphonicacids, where this function replaces the carboxyl in the original carboxylic acid. [on SciFinder (R)]
[EN] A CATALYST SYSTEM<br/>[FR] SYSTEME DE CATALYSEUR
申请人:LUCITE INT UK LTD
公开号:WO2005079981A1
公开(公告)日:2005-09-01
The present invention provides a catalyst system capable of catalysing the carbonylation of an ethylenically unsaturated compound, which system is obtainable by combining: a) a metal of Group VIB or Group VIIIB or a compound thereof, b) a bidentate phosphine, arsine or stibine ligand, and c) an acid, wherein said ligand is present in at least a 2:1 molar excess compared to said metal or said metal in said metal compound, and that said acid is present in at least a 2:1 molar excess compared to said ligand, a process for the carbonylation of an ethylenically unsaturated compound, a reaction medium, and use of the system.
Assembly, disassembly and reassembly: a “top-down” synthetic strategy towards hybrid, mixed-metal {Mo<sub>10</sub>Co<sub>6</sub>} POM clusters
作者:Colm Healy、Friedrich W. Steuber、Paul Wix、Lauren K. Macreadie、Amal Cherian Kathalikkattil、Wolfgang Schmitt
DOI:10.1039/c9dt00075e
日期:——
Polyoxometalates (POMs) are commonly prepared using a “bottom-up” synthetic procedure. The alternative “top-down” approach of disassembling a pre-formed POM unit to generate new synthetic intermediates is promising, but relatively comparatively underused. In this paper, a rationale for the top-down method is provided, demonstrating that this approach can generate compounds that are fundamentally inaccessible
多金属氧酸盐(POM)通常使用“自下而上”的合成程序进行制备。拆卸预成型的POM单元以生成新的合成中间体的另一种“自上而下”的方法是有前途的,但相对而言却未得到充分利用。在本文中,提供了自上而下方法的基本原理,证明了该方法可以生成从简单的自下而上的装配基本上无法获得的化合物。我们通过合成10种新的具有通式[TBA] 2 [Mo VI 10 Co II 6 O 30(R p PO 3)6(R c POO)的混合金属混合化合物来证明这一原理。2(L) x(H 2 O) 6 ](TBA =四丁基铵,R p =膦酸酯部分,R c =羧酸酯部分,L =吡啶基配体, x = 2-4),包括基于一维多金属氧酸盐的配位聚合物。我们建议这些结构是从Mo x O 3 x -1 }片段生成的,这些片段无法单独从下而上的程序集访问。POM簇由三类不同的有机配体(有机膦酸酯,羧酸酯和吡啶基配体)稳定化,它们各自可