Palladium-catalyzed Cycloaddition of Alkynyl Aryl Ethers to Allenes to Form a 2,3-Bismethylidene-2,3-dihydro-4<i>H</i>-1-benzopyran Framework
作者:Yasunori Minami、Mayuko Kanda、Tamejiro Hiyama
DOI:10.1246/cl.130894
日期:2014.2.5
Palladium-catalyzed cycloaddition of alkynyl aryl ethers to allenes proceeds through o-C–H activation to give 2,3-dihydro-4H-1-benzopyran derivatives containing 2,3-exo-double bonds. These benzopyr...
Cobalt‐Catalyzed Regio‐ and Stereoselective Hydroboration of Allenes
作者:Can Li、Zheng Yang、Lei Wang、Yinlong Guo、Zheng Huang、Shengming Ma
DOI:10.1002/anie.201915716
日期:2020.4.6
pincer-ligand-based cobalt-complex-catalyzed allenehydroboration affording Z-allylic boronates is described. The reaction demonstrates an excellent regio- as well as Z-stereoselectivity and a wide substrate scope that tolerates many functional groups. Based on solvent-assisted electrospray ionization mass spectrometry (SAESI-MS) studies, a rationale for the cobalt-catalyzed hydroboration involving the highly selective
Selective mono- and di-allylation and allenylation of chlorosilanes using indium
作者:Zhifang Li、Chenjun Yang、Hongfang Zheng、Huayu Qiu、Guoqiao Lai
DOI:10.1016/j.jorganchem.2008.08.028
日期:2008.12
Allyl and allenyl groups have been introduced into silicon systems by the allylation and allenylation of chlorosilanes using allylbromide or propargyl bromide with indium. The allylation of chlorosilanes afforded a variety of aryl, aralkyl, and alkenyl substituted allylsilanes. By applying this method, the reactions of 1-bromo-3-methylbut-2-ene, 3-bromo-2-methylprop-1-ene and 3-bromobut-1-ene with
A highly regio‐ and stereoselective copper‐catalyzed borylcupration of 1,2‐allenylsilanes affords an unexpected regioreversed allylic boronate bearing an extra C−Si bond at the 3‐position, with a thermodynamically disfavored Z geometry. Such stereodefined allylic boronates containing an extra alkenyl silane moiety are very useful organodimetallic reagents for organic synthesis.
[reaction: see text] The catalytic, enantioselective [3 + 2] cycloaddition reaction of 1-alkyl-substituted allenylsilanes with alpha-imino ester has been achieved by means of [Cu(MeCN)(4)]BF(4)/(R)-DM-SEGPHOS catalyst to afford silyl-substituted dehydroproline derivatives in high yields and enantioselectivities.