53450-82-1Relevant academic research and scientific papers
New insights into the biphasic “CO-free” Pauson-Khand cyclisation reaction through combinedin situspectroscopy and multiple linear regression modelling
Geitner, Robert,Huang, Tianbai,Kupfer, Stephan,Gr?fe, Stefanie,Meirer, Florian,Weckhuysen, Bert M.
, p. 1626 - 1636 (2021)
“CO-free” carbonylations are catalytic reactions, which strive to replace toxic synthesis gas with less harmful surrogate molecules like formaldehyde. This study sheds light on the mechanism of the biphasic, Rh-catalysed Pauson-Khand type cyclisation reaction by applyingin situRaman spectroscopy together with NMR, dynamic light scattering measurements, and quantum chemical calculations. The reaction is particularly challenging to analyse as the Rh-catalyst features different ligands in the aqueous and organic phase. To tackle this challenge, a novel approach was designed, couplingin situRaman spectroscopy with an advanced data analysis model in the form of multiple linear regression. This fruitful combination of highly specific vibrational spectroscopy with state-of-the-art data analysis allowed not only identification of a new reaction mechanism, but also identification of parameters to accelerate the “CO-free” Pauson-Khand cyclisation,i.e.using mononuclear Rh-phosphine complexes with labile ligands, small organic micelles formed by an increased surfactant concentration, low formaldehyde concentration, and elevated temperature. This novel knowledge-driven optimisation protocol is superior to simple qualitative optimization routines and can be transferred to other reactions and spectroscopy techniques.
Synthesis and characterization of [Rh(PP)(PP)]X complexes (PP = DPPE or DPPP, X = Cl? or BF4-). Phosphine exchange and reactivity in transfer hydrogenation conditions
Mannu, Alberto,Vlahopoulou, Gina,Kubis, Christoph,Drexler, Hans-Joachim
supporting information, p. 59 - 64 (2019/02/20)
The synthesis of heteroleptic monomeric cationic Rh(I) bis-diphosphine complex [Rh(dppe)(dppp)]Cl (dppe = 1,2-bis-(diphenylphosphino)ethane and dppp = 1,3-bis-(diphenylphosphino)propane) was achieved by reaction between the neutral dimeric complex [Rhsub
MONO- AND DINUCLEAR RHODIUM CARBONYL SPECIES CONTAINING MONODENTATE OR BRIDGING 1,3-BIS(DIPHENYLPHOSPHINO)PROPANE
Fung, Dawning C. M.,James, Brian R.
, p. 329 - 334 (2007/10/02)
The interaction of 2(μ-CO)2 with H2 in CH2Cl2 in the presence of varying amounts of dpp leads mainly to catalytically important species which include Rh(H)CO)(dpp)(dpp*) and 2(μ-dpp), these being formed also by treating RhH(dpp)2 with about 2 equivalents of CO; dpp and dpp* = bidentate and monodentate 1,3-bis(diphenylphosphino)propane, respectively.Mechanistic pathways involving a detected RhH(CO)2(dpp) and a non-detected RhH(CO)(dpp) species are suggested.
