Novel decomplexation method for alkyne–Co2(CO)6 complexes
摘要:
A novel and general decomplexation method for alkyne-Co-2(CO)(6) complexes has been established, which treats the complexes with ethylenediamine in THF. (C) 1998 Elsevier Science S.A. All rights reserved.
Platinum-Catalyzed Hydrosilylations of Internal Alkynes: Harnessing Substituent Effects to Achieve High Regioselectivity
作者:Douglas A. Rooke、Eric M. Ferreira
DOI:10.1002/anie.201108714
日期:2012.3.26
Rule of thumb: The high yielding title reaction is described with a focus on understanding the factors that govern the regioselectivity of the process (see scheme). Electronic, steric, and functional group properties all influence the selectivity, an understanding of which allows the selective formation of trisubstituted vinylsilanes, which are synthetically useful compounds for accessing stereodefined
An analysis of the influences dictating regioselectivity in platinum-catalyzed hydrosilylations of internal alkynes
作者:Douglas A. Rooke、Zachary A. Menard、Eric M. Ferreira
DOI:10.1016/j.tet.2014.03.012
日期:2014.7
A full account of our studies on internal alkyne hydrosilylations using platinum catalysis is described. We demonstrate that these transformations are highly governed by the electronic characteristics of the alkyne substituents, wherein the hydride will add preferentially to the more electron-deficient alkyne carbon. The steric and coordinative capabilities of the substituents influence the selectivity
完整介绍了我们对使用铂催化的内部炔烃氢甲硅烷基化的研究。我们证明,这些转变高度受炔烃取代基的电子特性支配,其中氢化物将优先添加至电子欠缺的炔烃碳上。取代基的空间和配位能力对选择性的影响程度要小得多,其中丙炔醇是唯一的例外。硅烷的选择在某些情况下是相关的。特定的硅烷将提供较高的区域选择性,而其他的则选择性要低得多。最终,使用13 C NMR化学位移数据可以完全预测加成的区域选择性,从而将这种反应性纳入目标反应设计中。
Ruthenium-Catalyzed Coupling of Oxabenzonorbornadienes with Alkynes Bearing a Propargylic Oxygen Atom: Access to Stereodefined Benzonorcaradienes
作者:Alphonse Tenaglia、Sylvain Marc、Laurent Giordano、Innocenzo De Riggi
DOI:10.1002/anie.201104589
日期:2011.9.19
Stereodefined: The title reaction provides an atom‐economic route to benzonorcaradienes. The diastereoselectivity of the coupling relies upon the structure of the alkene; unsubstituted bicyclic alkenes afforded exclusively exo‐benzonorcaradienes (see scheme) whereas the bicyclic alkenes with substituents at the bridgehead positions resulted in endo‐benzonorcaradienes.
Allenic samariumcomplexes are readily generated in high yields by the reaction of propargylic benzyl ethers with (C5Me5)2Sm(thf)2. Electrophilic trapping of the complexes derived from the secondary and tertiary ethers with cyclohexanone and dimethylphenylsilyl chloride gives the corresponding propargylic products selectively, whereas α-allenic alcohols are predominantly obtained in the reaction of
通过炔丙基苄基醚与(C 5 Me 5)2 Sm(thf)2的反应,可以容易地高收率生成烯丙基sa络合物。仲和叔醚衍生的配合物与环己酮和二甲基苯基甲硅烷基氯的亲电捕集选择性地产生相应的炔丙基产物,而α-烯丙醇主要是由伯醚生成的配合物与环己酮反应而获得的。