Reactions of Carbon Electrophiles with Cobalt-Coordinated Enynes: Scope and Limitations
作者:Herbert Mayr、Oliver Kuhn、Clemens Schlierf、Armin R Ofial
DOI:10.1016/s0040-4020(00)00347-1
日期:2000.6
increases the nucleophilic reactivity of enynes by a factor of > 106. The exchange of one CO ligand by PPh3 (2a→2d), however, has only little effect on the reactivity of the enyne moiety. The second-order rate constants match the linearfreeenergyrelationship lg k20°C=s(E+N) and allow to determine the nucleophilicity parameters N and s for 2a–d. It is shown that at −70°C, electrophiles with E>0 are able to
<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
A mild and facile Peterson olefination has been developed employing low catalyst loading of the Brønstedacid HNTf2. The reactions are typically performed at room temperature, with the reaction tolerant to a range of useful functionalities. Furthermore, we have extended this methodology to the synthesis of enynes.
作者:John A. Soderquist、Karl Matos、Anil Rane、Jorge Ramos
DOI:10.1016/0040-4039(95)00322-4
日期:1995.4
The addition of B-methoxy-9-borabicyclo[3.3.1]nonane (1) to alkynyllithium reagents gives stable complexes (2) which undergo efficient Suzuki-Miyauracoupling to produce a variety of alkynyl derivatives (3).
Halotrifluoromethylation of 1,3-Enynes: Access to Tetrasubstituted Allenes
作者:Jinfeng Huang、Yimin Jia、Xiangyu Li、Jianli Duan、Zhong-Xing Jiang、Zhigang Yang
DOI:10.1021/acs.orglett.1c00449
日期:2021.3.19
regioselective copper-catalyzed 1,4-chloro- and bromotrifluoromethylation of 1,3-enynes has been presented for the first time, which affords an efficient transformation to access halo- and CF3-containing tetrasubstituted allene derivatives with good to excellent yield. This protocol is practical and convenient, in which a wide range of functional groups are compatible. Applications of this method for the gram-scale