18752-20-0Relevant articles and documents
Hydrosilylation of Aldehydes and Ketones Catalyzed by a 2-Iminopyrrolyl Alkyl-Manganese(II) Complex
Cruz, Tiago F. C.,Veiros, Luís F.,Gomes, Pedro T.
supporting information, p. 1195 - 1206 (2022/01/11)
A well-defined and very active single-component manganese(II) catalyst system for the hydrosilylation of aldehydes and ketones is presented. First, the reaction of 5-(2,4,6-iPr3C6H2)-2-[N-(2,6-iPr2C6H3)formimino]pyrrolyl potassium (KL) and [MnCl2(Py)2] afforded the binuclear 2-iminopyrrolyl manganese(II) pyridine chloride complex [Mn2{κ2N,N′-5-(2,4,6-iPr3C6H2)-NC4H2-2-C(H)═N(2,6-iPr2C6H3)}2(Py)2(μ-Cl)2] 1. Subsequently, the alkylation reaction of complex 1 with LiCH2SiMe3 afforded the respective (trimethylsilyl)methyl-Mn(II) complex [Mn{κ2N,N′-5-(2,4,6-iPr3C6H2)-NC4H2-2-C(H)═N(2,6-iPr2C6H3)}(Py)CH2SiMe3] 2 in a good yield. Complexes 1 and 2 were characterized by elemental analysis, 1H NMR spectroscopy, Evans' method, FTIR spectroscopy, and single-crystal X-ray diffraction. While the crystal structure of complex 1 has been identified as a binuclear entity, in which the Mn(II) centers present pentacoordinate coordination spheres, that of complex 2 corresponds to a monomer with a distorted tetrahedral coordination geometry. Complex 2 proved to be a very active precatalyst for the atom-economic hydrosilylation of several aldehydes and ketones under very mild conditions, with a maximum turnover frequency of 95 min-1, via a silyl-Mn(II) mechanistic route, as asserted by a combination of experimental and theoretical efforts, the respective silanes were cleanly converted to the respective alcoholic products in high yields.
Mononuclear Heteroscorpionate Zwitterionic Zinc Terminal Hydride: Synthesis, Reactivity, and Catalysis for Hydrosilylation of Aldehydes
Mou, Zehuai,Xie, Hongyan,Wang, Meiyan,Liu, Na,Yao, Changguang,Li, Lei,Liu, Jingyao,Li, Shihui,Cui, Dongmei
, p. 3944 - 3949 (2015/09/01)
Treatment of heteroscorpionate zinc benzyloxy complex LZnOBn (1, L = (MePz)2CP(Ph)2NPh, MePz = 3,5-dimethylpyrazolyl) with phenylsilane (PhSiH3) gave a zinc hydride complex LZnH (2) containing a rare terminal hydride fragment. X-ray diffraction analysis and the DFT calculation confirm the zwitterionic structure of complex 2. The stoichiometric reaction of 2 with CS2 readily afforded a dithioformate complex LZnSCH(S) (3) of the C = S insertion into the Zn-H product. Moreover, complex 2 was an efficient catalyst for the hydrosilylation reaction of a series of silanes and aldehydes under mild conditions, featuring excellent functional group tolerance. The preliminary mechanistic study revealed that both zinc benzyloxy complex 1 and zinc hydride complex 2 were involved in the hydrosilylation process as the reaction intermediates. (Chemical Equation Presented).
Rare-earth metal allyl and hydrido complexes supported by an (NNNN)-type macrocyclic ligand: Synthesis, structure, and reactivity toward biomass-derived furanics
Abinet, Elise,Martin, Daniel,Standfuss, Sabine,Kulinna, Heiko,Spaniol, Thomas P.,Okuda, Jun
experimental part, p. 15014 - 15026 (2012/02/06)
The preparation and characterization of a series of neutral rare-earth metal complexes [Ln(Me3TACD)(η3-C3H 5)2] (Ln=Y, La, Ce, Pr, Nd, Sm) supported by the 1,4,7-trimethyl-1,4,7,10-tetraazacyclododecane anion (Me3TACD -) are reported. Upon treatment of the neutral allyl complexes [Ln(Me3TACD)(η3-C3H5) 2] with Bronsted acids, monocationic allyl complexes [Ln(Me3TACD)(η3-C3H5)(thf) 2][B(C6X5)4] (Ln=La, Ce, Nd, X=H, F) were isolated and characterized. Hydrogenolysis gave the hydride complexes [Ln(Me3TACD)H2]n (Ln=Y, n=3; La, n=4; Sm). X-ray crystallography showed the lanthanum hydride to be tetranuclear. Reactivity studies of [Ln(Me3TACD)R2]n (R=η3-C3H5, n=0; R=H, n=3,4) towards furan derivatives includes hydrosilylation and deoxygenation under ring-opening conditions.
