1536256-47-9Relevant academic research and scientific papers
Terminal hydridozinc cation
Chambenahalli, Raju,Andrews, Alex P.,Ritter, Florian,Okuda, Jun,Venugopal, Ajay
, p. 2054 - 2057 (2019)
A thermally stable terminal hydridozinc cation has been isolated. The nucleophilicity of the hydride ligand is demonstrated by inserting carbon dioxide, carbodiimide and benzophenone across the Zn-H bond in a facile manner. Preliminary studies on catalyti
Hydrosilylation of Aldehydes and Ketones Catalyzed by a Terminal Zinc Hydride Complex, [κ3-Tptm]ZnH
Sattler, Wesley,Ruccolo, Serge,Rostami Chaijan, Mahnaz,Nasr Allah, Tawfiq,Parkin, Gerard
, p. 4717 - 4731 (2015/10/28)
Tris(2-pyridylthio)methyl zinc hydride, [κ3-Tptm]ZnH, is an effective catalyst for multiple insertions of carbonyl groups into the Si-H bonds of PhxSiH4-x (x = 1, 2). Specifically, [κ3-Tptm]ZnH catalyzes the insertion of a variety of aldehydes and ketones into the Si-H bonds of PhSiH3 and Ph2SiH2 to afford PhSi[OCH(R)R′]3 and Ph2Si[OCH(R)R′]2, respectively. The mechanism for hydrosilylation is proposed to involve insertion of the carbonyl group into the Zn-H bond to afford an alkoxy species, followed by metathesis with the silane to release the alkoxysilane and regenerate the zinc hydride catalyst. Multiple insertion of prochiral ketones results in the formation of diastereomeric mixtures of alkoxysilanes that can be identified by NMR spectroscopy.
A Pentacoordinate Mn(II) Precatalyst That Exhibits Notable Aldehyde and Ketone Hydrosilylation Turnover Frequencies
Ghosh, Chandrani,Mukhopadhyay, Tufan K.,Flores, Marco,Groy, Thomas L.,Trovitch, Ryan J.
supporting information, p. 10398 - 10406 (2015/11/16)
Heating (THF)2MnCl2 in the presence of the pyridine-substituted bis(imino)pyridine ligand, PyEtPDI, allowed preparation of the respective dihalide complex, (PyEtPDI)MnCl2. Reduction of this precursor using excess Na/Hg resulted in deprotonation of the chelate methyl groups to yield the bis(enamide)tris(pyridine)-supported product, (κ5-N,N,N,N,N-PyEtPDEA)Mn. This complex was characterized by single-crystal X-ray diffraction and found to possess an intermediate-spin (S = 3/2) Mn(II) center by the Evans method and electron paramagnetic resonance spectroscopy. Furthermore, (κ5-N,N,N,N,N-PyEtPDEA)Mn was determined to be an effective precatalyst for the hydrosilylation of aldehydes and ketones, exhibiting turnover frequencies of up to 2475 min-1 when employed under solvent-free conditions. This optimization allowed for isolation of the respective alcohols and, in two cases, the partially reacted silyl ethers, PhSiH(OR)2 [R = Cy and CH(Me)(nBu)]. The aldehyde hydrosilylation activity observed for (κ5-N,N,N,N,N-PyEtPDEA)Mn renders it one of the most efficient first-row transition metal catalysts for this transformation reported to date.
A highly active manganese precatalyst for the hydrosilylation of ketones and esters
Mukhopadhyay, Tufan K.,Flores, Marco,Groy, Thomas L.,Trovitch, Ryan J.
supporting information, p. 882 - 885 (2014/02/14)
The reduction of (Ph2 PPrPDI)MnCl2 allowed the preparation of the formally zerovalent complex, (Ph2 PPrPDI)Mn, which features a pentadentate bis(imino)pyridine chelate. This complex is a highly active precatalyst for the hydrosilylation of ketones, exhibiting TOFs of up to 76,800 h-1 in the absence of solvent. Loadings as low as 0.01 mol % were employed, and (Ph2 PPrPDI)Mn was found to mediate the atom-efficient utilization of Si-H bonds to form quaternary silane products. (Ph2PPrPDI)Mn was also shown to catalyze the dihydrosilylation of esters following cleavage of the substrate acyl C-O bond. Electronic structure investigation of (Ph 2PPrPDI)Mn revealed that this complex possesses an unpaired electron on the metal center, rendering it likely that catalysis takes place following electron transfer to the incoming carbonyl substituent.
