New Fischer Carbene Complexes of Rhodium(I): Preparation and 2-Cyclopentenone Ring Synthesis by Annelation to Alkynes
作者:José Barluenga、Rubén Vicente、Luis A. López、Eduardo Rubio、Miguel Tomás、Carmen Álvarez-Rúa
DOI:10.1021/ja038817q
日期:2004.1.1
A new type of metal carbene complexes of group 9, specifically a cationic Fischer carbene of rhodium(I), has been synthesized from chromium carbene complexes via double transfer of carbene and CO ligands. These complexes reveal a different reactivity than other transition metal carbenes, including their chromium precursors, toward neutral and electron-poor alkynes, giving selectively polysubstituted
已经从铬卡宾配合物通过卡宾和 CO 配体的双重转移合成了一种新型的第 9 族金属卡宾配合物,特别是铑 (I) 的阳离子费歇尔卡宾。这些配合物显示出与其他过渡金属卡宾(包括其铬前体)对中性和缺电子炔的反应性不同,从而产生选择性多取代的环戊烯酮。
Copper(II)-Catalyzed β-Borylation of Acetylenic Esters in Water
作者:Webster Santos、Cheryl Peck、Joseph Calderone
DOI:10.1055/s-0034-1380524
日期:——
presence of bis(pinacolato)diboron and catalytic amounts of both copper(II) and 4-picoline, substituted alkynoates undergo borylation in a regio-, stereo-, and chemoselective fashion. The reaction is performed under mild conditions using water as solvent and open to the atmosphere to exclusively afford (Z)-β-boryl-α,β-unsaturated esters. A method for the β-borylation of alkynoates has been developed
A novel synthesis of oxazolidine-2,4-diones via an efficient fixation of CO<sub>2</sub>with 3-aryl-2-alkynamides
作者:Guofei Chen、Chunling Fu、Shengming Ma
DOI:10.1039/c0ob00550a
日期:——
A very mild protocol for fixation of carbon dioxide with 2-alkynamides in DMSO at 30 °C using a CO2 balloon in the presence of K2CO3 has been developed, which leads to an efficient assembly of oxazolidine-2,4-diones. It is observed that the regioselectivity was controlled by the aryl group.
The Vinyl Moiety as a Handle for Regiocontrol in the Preparation of Unsymmetrical 2,3-Aliphatic-Substituted Indoles and Pyrroles
作者:Malcolm P. Huestis、Lina Chan、David R. Stuart、Keith Fagnou
DOI:10.1002/anie.201006381
日期:2011.2.7
enynes with N‐aryl ureas (X=NR2) and N‐vinylacetamides (X=C(O)Me), affording the corresponding 2‐alkenylindoles and 2‐alkenylpyrroles in good yield. Simple hydrogenation delivers the C2/C3‐aliphatic‐substituted indole or pyrrole (see scheme).
Rho-Rho-Rho您的小船:铑催化剂可实现烯炔与N-芳基脲(X = NR 2)和N-乙烯基乙酰胺(X = C(O)Me)的区域选择性氧化偶联,提供相应的2-烯基吲哚和2-烯基吡咯的收率好。简单的氢化作用即可得到C2 / C3脂肪族取代的吲哚或吡咯(参见方案)。
Siloxy(trialkoxy)ethene undergoes regioselective [2+2] cycloaddition to ynones and ynoates en route to functionalized cyclobutenediones
作者:Shin Iwata、Toshiyuki Hamura、Keisuke Suzuki
DOI:10.1039/c0cc00883d
日期:——
Regioselective [2+2] cycloaddition of ynones or ynoates to siloxy(trialkoxy)ethene (KSA) is described. A siloxy group on the KSA directs the perfect regioselectivity, allowing rapid construction of various functionalized cyclobutenedione derivatives.