Co/Rhheterobimetallic nanoparticles were prepared from cobalt-rhodium carbonyl clusters [Co2Rh2(CO)12 and Co3Rh(CO)12] and immobilized on charcoal. HR-TEM revealed that the size of the heterobimetallic nanoparticles was ca. 2 nm and ICP-AES analysis showed a 2 : 2 and a 3 : 1 cobalt-rhodium stoichiometry (Co2Rh2 and Co3Rh1) in the heterobimetallic nanoparticles. The Co/Rhheterobimetallic nanoparticles
PNSO Ligands as a Tool to Study Metal Bonding of Electron‐Deficient Sulfinyl Groups
作者:Marc Revés、Antoni Riera、Xavier Verdaguer
DOI:10.1002/ejic.200900521
日期:2009.10
N-phosphanylsulfinamide (PNSO) ligands with electron-deficient sulfinylgroups was synthesized. Reaction with Co2–alkyne complexes yields P,S-bridged complexes. These complexes were used to study the metalbonding of different sulfinylgroups. IR spectroscopy, X-ray analysis, and Pauson–Khand reactivity studies indicated that electrondeficient sulfinylgroups provide enhanced S metalbonding.
Acetylene−Dicobaltcarbonyl Complexes with Chiral Phosphinooxazoline Ligands: Synthesis, Structural Characterization, and Application to Enantioselective Intermolecular Pauson−Khand Reactions
作者:Jaume Castro、Albert Moyano、Miquel A. Pericàs、Antoni Riera、Angel Alvarez-Larena、Joan F. Piniella
DOI:10.1021/ja001143o
日期:2000.8.23
of the diastereomer nonchelated complexes 11a,b−15a,b. The interconversion rate between diastereomeric pairs is dependent on the steric bulk of the alkyne substituent, and neither 3 nor 5 epimerize at room temperature. The structures of both kinds of complexes have been ascertained by a combination of spectroscopical (IR, NMR), X-ray diffraction, and chiroptical methods; this has allowed the development
Intermolecular Cobalt-Mediated Pauson-Khand Reactions in Ionic Liquids
作者:Sabine Laschat、Armand Becheanu
DOI:10.1055/s-2002-34892
日期:——
IntermolecularPauson-Khandreactions of strained alkenes la-d with alkynes 2, 4, 6 and Co 2 (CO) 8 were performed in [bmim]PF 6 either thermally or in the presence of NMO. For comparison thermal reactions were done in toluene and NMO-promoted reactions in CH 2 Cl 2 . The results show that the ionic liquid is a suitable substitute for CH 2 Cl 2 . Yields of the NMO-promoted reaction could be improved
The Catalytic Pauson-Khand Reaction Promoted by A Small Amount of 1,2-Dimethoxyethane or Water
作者:Takumichi Sugihara、Masahiko Yamaguchi
DOI:10.1055/s-1998-1991
日期:1998.12
Various "hard" Lewis bases having less nucleophilic nature promoted the catalytic Pauson-Khand reaction. Among those Lewis bases, 1,2-dimethoxyethane seems to be the most promising promoter and a small amount of water, which is the cheapest reagent, also effectively promoted the cyclization.