1176190-67-2Relevant academic research and scientific papers
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.
Synthesis and thermal properties of silicon-containing epoxy resin used for UV-curable flame-retardant coatings
Cheng, Xi-E,Shi, Wenfang
experimental part, p. 303 - 310 (2011/04/26)
A novel silicon-containing trifunctional cycloaliphatic epoxide resin tri(3,4-epoxycyclohexylmethyloxy) phenyl silane (TEMPS) was synthesized and characterized by FTIR, 1H NMR, 13C NMR, and 29Si NMR spectroscopic analysis. A series of flame-retardant formulations by blending TEMPS with a commercial epoxide resin DGEBA (EP828) in different ratios were prepared, and exposed to a medium pressure lamp to form the cured films in the presence of diaryliodonium hexafluorophosphate salt as a cationic photoinitiator. The thermal degradation behaviors of the cured films were evaluated by thermogravimetric analysis. The char yields under nitrogen and air atmospheres increased along with the TEMPS content. The limiting oxygen index (LOI) value increased from 22 for EP828 to 30 for TEMPS80, demonstrating the improved flame retardancy. The data from the dynamic mechanical thermal analysis showed that TEMPS had good miscibility with EP828. The T s and T g both decreased from 93 and 138 to 78 and 118 °C, respectively. The crosslinking density (ν e) increased along with the TEMPS content. The mechanical property measurements indicated that the addition of TEMPS led to a decrease in the tensile strength and an increase in the elongation-at-break.
