<i>gem</i>-Selective Cross-Dimerization and Cross-Trimerization of Alkynes with Silylacetylenes Promoted by a Rhodium-Pyridine-<i>N</i>-Heterocyclic Carbene Catalyst
作者:Ramón Azpíroz、Laura Rubio-Pérez、Ricardo Castarlenas、Jesús J. Pérez-Torrente、Luis A. Oro
DOI:10.1002/cctc.201402327
日期:2014.9
The gem‐selective cross‐dimerization and ‐trimerization of silylacetylenes with alkynes through CH activation using a rhodium(I)–pyridine–N‐heterocyclic carbene catalyst have been developed. This reaction is applied to various aliphatic or aromatic terminal alkynes, internal alkynes, and gem‐1,3‐disubsituted enynes to afford the corresponding enynes and dienynes with high regio‐ and stereoselectivities
The cross-coupling of a number of internal arylalkynes with a representative terminal alkyne, tert-butyldimethylsilylacetylene, proceeds regio- and stereoselectively in the presence of a rhodium catalyst to produce the corresponding enyne compounds with good yield.
Palladium-catalyzed trans-selective alkynylation–alkylation tandem process for the synthesis of (E)-3-alkyl-1-trialkylsilyl-3-alken-1-ynes
作者:Ei-ichi Negishi、Ji-cheng Shi、Xingzhong Zeng
DOI:10.1016/j.tet.2005.07.100
日期:2005.10
The Pd-catalyzed trans-selective monoalkynylation of 1,1-dihalo-l-alkenes with XZnC CSiMe3, where X is Br or Cl, can proceed generally in excellent yields in the presence of Pd(DPEphos)Cl-2 or Pd(dppf)Cl-2, and subsequent alkylation with methyl- and ethylzincs can proceed in excellent yields with >= 98% retention of configuration in the presence of Pd((BU3P)-B-t)(2) as a catalyst. (c) 2005 Elsevier Ltd. All rights reserved.