Rapid Metal-Free Formation of Free Phosphines from Phosphine Oxides
作者:Cei B. Provis-Evans、Emma A. C. Emanuelsson、Ruth L. Webster
DOI:10.1002/adsc.201800723
日期:2018.10.18
A rapid method for the reduction of secondary phosphineoxides under mild conditions has been developed, allowing simple isolation of the corresponding free phosphines. The methodology involves the use of pinacol borane (HBpin) to effect the reduction while circumventing the formation of a phosphine borane adduct, as is usually the case with various other commonly used borane reducing agents such as
A Superior Method for the Reduction of Secondary Phosphine Oxides
作者:Carl A. Busacca、Jon C. Lorenz、Nelu Grinberg、Nizar Haddad、Matt Hrapchak、Bachir Latli、Heewon Lee、Paul Sabila、Anjan Saha、Max Sarvestani、Sherry Shen、Richard Varsolona、Xudong Wei、Chris H. Senanayake
DOI:10.1021/ol0517832
日期:2005.9.1
to be outstanding reductants for secondaryphosphineoxides (SPOs). All classes of SPOs can be readily reduced, including diaryl, arylalkyl, and dialkyl members. Many SPOs can now be reduced at cryogenic temperatures, and conditions for preservation of reducible functional groups have been found. Even the most electron-rich and sterically hindered phosphineoxides can be reduced in a few hours at 50-70
Ir-Catalyzed Double Asymmetric Hydrogenation of 3,6-Dialkylidene-2,5-diketopiperazines for Enantioselective Synthesis of Cyclic Dipeptides
作者:Yao Ge、Zhaobin Han、Zheng Wang、Kuiling Ding
DOI:10.1021/jacs.9b02920
日期:2019.6.5
synthesis of 6a and efficient construction of chiral products 8, 14, and 17 as well as a 2-butenyl-bridged bicyclic diketopiperazine 10 and hydroxydiketopiperazine 11. With an analogous achiral Ir catalyst, the hydrogenation of enantiopure monohydrogenated intermediate 7a gave cis-6a as the only product, indicating that the second-step hydrogenation of the titled transformation is a chiral substrate controlled
Construction of Benzo-1,2,3-thiazaphosphole Heterocycles by Annulations of <i>ortho</i>-Phosphinoarenesulfonyl Fluorides with Trimethylsilyl Azide
作者:Wenjun Luo、Zhenguo Wang、Xiaohui Cao、Dacheng Liang、Mingjie Wei、Keshu Yin、Le Li
DOI:10.1021/acs.joc.0c01309
日期:2020.11.20
Annulations of ortho-phosphinoarenesulfonyl fluorides with trimethylsilylazide were developed to access an unprecedented benzo-1,2,3-thiazaphosphole heterocycle. A corresponding reaction mechanism was proposed and further elucidated by experimental and computational studies. The reaction proceeds through a Staudinger-type iminophosphorane intermediate followed by intramolecular trapping with sulfonyl
Hydrogen/Halogen Exchange of Phosphines for the Rapid Formation of Cyclopolyphosphines
作者:Adam N. Barrett、Callum R. Woof、Christopher A. Goult、Danila Gasperini、Mary F. Mahon、Ruth L. Webster
DOI:10.1021/acs.inorgchem.1c02734
日期:2021.11.1
The hydrogen/halogen exchange of phosphines has been exploited to establish a truly useable substrate scope and straightforward methodology for the formation of cyclopolyphosphines. Starting from a single dichlorophosphine, a sacrificial proton “donor phosphine” makes the rapid, mild synthesis of cyclopolyphosphines possible: reactions are complete within 10 min at room temperature. Novel (aryl)cyclopentaphosphines