Brønsted Base Mediated Stereoselective Diphosphination of Terminal Alkynes with Diphosphanes
作者:Yuto Okugawa、Koji Hirano、Masahiro Miura
DOI:10.1021/acs.orglett.7b01209
日期:2017.6.2
A Brønsted base mediated stereoselective diphosphination of terminal alkynes with diphosphanes proceeds to deliver the corresponding (E)-1,2-diphosphinoethenes in good yields. The reaction of aromatic alkynes occurs efficiently in the presence of a catalytic amount of LiO-t-Bu while MN(TMS)2 (M = Li or Na) gave better results in the case of aliphatic substrates. The Brønsted base mediated protocol
development of new synthetic methods by using air‐stable sources of phosphorus. In this respect, a synthetic method that is based on a reductive rearrangement and is capable of converting air‐stable pentavalent phosphorus compounds into reactive trivalent phosphorus compounds is a powerful tool. Tetraphenyldiphosphine disulfide, which is a shelf‐stable solid, was the focus of this study, and it was
A novel transition-metal-catalyzed hydrophosphination of terminal alkynes using a diphosphine-hydrosilane binary system takes place regioselectively to provide vinylic phosphines, which undergo air oxidation during workup, affording the corresponding vinylphosphine oxides in good yields. In this hydrophosphination, hydrosilanes act as a useful hydrogen source, and furthermore, small amounts of oxygen is required to accomplish the reaction efficiently.
Photochemical behaviors of tetraphenyldiphosphine in the presence of alkynes
Under an atmosphere of nitrogen, the photoinduced reaction of tetraphenyldiphosphine (1) with alkynes (2) generates vicinal bisphosphinated alkenes (3) as air-sensitive compounds, which can be isolated by treatment with elemental sulfur. A novel E to Z isomerization of 3 is revealed to take place upon continuous photoirradiation. (c) 2006 Elsevier Ltd. All rights reserved.