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
Synthesis and Application of Tetraphosphane Ligands in Rhodium-Catalyzed Hydroformylation of Terminal Olefins: High Regioselectivity at High Temperature
A new class of substituted tetraphosphane ligands has been developed and applied in the rhodium‐catalyzed regioselective hydroformylation of terminal olefins. The high regioselectivity (linear selectivity is above 97 % for 1‐octene and 1‐hexene) at high temperature (140 °C) shown by these tetraphosphane ligands is remarkable considering the low regioselectivity commonly observed under similar reaction
Catalytic Asymmetric Silane Alcoholysis: Practical Access to Chiral Silanes
作者:Darby R. Schmidt、Steven J. O'Malle、James L. Leighton
DOI:10.1021/ja0283201
日期:2003.2.1
A new asymmetric synthesis of chiral silanes has been developed. Chiral phosphine-modified copper complexes catalyze the alcoholysis of prochiral dihydrosilanes with good to excellent stereoselectivity at silicon. The application of this methodology to the tandem silylformylation-allylsilylation of alkynes has been demonstrated.
Synthesis of and hydroformylation with fluoro-substituted bidentate
申请人:Hoechst Celanese Corporation
公开号:US05567856A1
公开(公告)日:1996-10-22
Hydroformylation of alkenes to aldehydes in the presence of a rhodium complex catalyst is improved by the addition of a novel bidentate ligand of the formula ##STR1## wherein R.sub.1, R.sub.2, R.sub.1 ' and R.sub.2 ' are organic radicals selected from alicyclic, aliphatic and aromatic groups of which at least one is preferably substituted with at least one electronegative moiety and the methylene groups are present at the trans-2,3 positions on the norbornane moiety. The invention also provides a novel method for producing the bidentate ligand and novel intermediate phosphine oxide and phosphinous acid compounds.
Branched-Selective Hydroformylation of Nonactivated Olefins Using an N-Triphos/Rh Catalyst
作者:Andreas Phanopoulos、Kyoko Nozaki
DOI:10.1021/acscatal.8b00566
日期:2018.7.6
We report a catalytic system comprised of nitrogen-centered di- or triphosphine ligands in conjunction with rhodium that is capable of delivering branched aldehydes from terminal olefin substrates which commonly give more linear aldehydes than branched. The incorporation of an apical nitrogen atom into the ligand backbone dramatically improves the reaction rate. Mechanistic and labeling studies suggest