Subtleties in asymmetric catalyst structure: the resolution of a 6-phospha-2,4,8-trioxa-adamantane and its applications in asymmetric hydrogenation catalysis
Evaluation of P-bridged biaryl phosphine ligands in palladium-catalysed Suzuki–Miyaura cross-coupling reactions
作者:Jairus L. Lamola、Paseka T. Moshapo、Cedric W. Holzapfel、Munaka Christopher Maumela
DOI:10.1039/d1ra04947j
日期:——
A family of biaryl phosphacyclic ligands derived from phobane and phosphatrioxa-adamantane frameworks is described. The rigid biaryl phosphacycles are efficient for Suzuki–Miyauracross-coupling of aryl bromides and chlorides. In particular, coupling reactions of the challenging sterically hindered and heterocyclic substrates were viable at room temperature.
[EN] PROCESS FOR THE CARBONYLATION OF A CONJUGATED DIENE<br/>[FR] PROCEDE PERMETTANT LA CARBONYLATION D'UN DIENE CONJUGUE
申请人:SHELL INT RESEARCH
公开号:WO2004103948A1
公开(公告)日:2004-12-02
A process for the carbonylation of a conjugated diene, comprising reacting the conjugated diene with carbon monoxide and a co-reactant having a mobile hydrogen atom in the presence of a catalyst system including: (a) a source of palladium; and (b) a bidentate diphosphine ligand of formula (II): R1R2 > p1R3m-R-R4n-p2 < R5R6 wherein p1 and p2 represent phosphorus atoms; R1, R2, R5, and R6 independently represent the same or different optionally substituted organic radical containing a tertiary carbon atom through which each radical is linked to the phosphorus atom; R3 and R4 independently represent the same or different optionally substituted methylene groups; R represents an organic group comprising the bivalent bridging group C1-C2 through which R is connected to R3 and R4; m and n independently represent a natural number in the range of from 0 to 4, wherein the rotation about the bond between the carbon atoms C1 and C2 of the bridging group is restricted a temperature in the range of from 0 °C to 250 °C, and wherein the dihedral angle between the plane occupied by the three atom sequence composed of C1, C2 and the atom directly bonded to C1 in the direction of p1, and the plane occupied by the three atom sequence C1, C2 and the atom directly bonded to C2 in the direction of p2, is in the range of from 0 to 120°; and (c) a source of an anion.
Designing biaryl phosphacyclic ligands: their characterization and evaluation in palladium-catalyzed Suzuki-Miyaura reactions of aryl bromides and chlorides
作者:Jairus L. Lamola、Paseka T. Moshapo、Cedric W. Holzapfel、Munaka Christopher Maumela
DOI:10.1080/10426507.2021.2012178
日期:2022.6.3
Abstract Efficient palladium catalyst systems based on the combination of bench stable biaryl phosphacycles and Pd(OAc)2 are described for Suzuki-Miyauracross-coupling reactions of aryl bromides and chlorides. Notably, the electronically and sterically diametric biaryl phosphacycles allowed facile coupling of sterically hindered and heterocyclic substrates.
An Exclusively
<i>trans</i>
‐Selective Chlorocarbamoylation of Alkynes Enabled by a Palladium/Phosphaadamantane Catalyst
作者:Christine M. Le、Xiao Hou、Theresa Sperger、Franziska Schoenebeck、Mark Lautens
DOI:10.1002/anie.201507883
日期:2015.12.21
synthesized by a palladium(0)‐catalyzed intramolecular chlorocarbamoylation reaction of alkynes. A relatively underexplored class of caged phosphine ligands is uniquely suited for this transformation, enabling high levels of reactivity and exquisite transselectivity. This report entails the first transition‐metal‐catalyzed atom‐economic addition of a carbamoyl chloride across an alkyne.
Coordination Studies of a New Nonsymmetric Ditertiary Phosphane Bearing a Single Phosphaadamantane Cage
作者:Tom J. Cunningham、Mark R. J. Elsegood、Paul F. Kelly、Martin B. Smith、Paul M. Staniland
DOI:10.1002/ejic.200800059
日期:2008.5
P'-chelate complexescis-[PdCl 2 (1)] (2) and cis-[Pt(CH 3 ) 2 (1)] (3), respectively. The dinuclear gold(I) complex [Ph 2 P(AuCl)-(CH 2 ) 2 PAd(AuCl)] (4) was prepared from 1 and 2 equiv. of [AuCl(tht)] (tht = tetrahydrothiophene). In contrast, the cleavage of the chloro-bridged dimers RuCl 2 (η 6 -P-cymene)}2 or (MCl 2 (n 5 -Cp*)} 2 (M = Rh, Ir) with 1 gave the K 1 -P-monodentate complexes [RuCl2(η