[(PhBP<sub>3</sub>)Cu(PPh<sub>3</sub>)] as a Surrogate of Tp<sup>x</sup>CuL in Homogeneous Catalysis (PhBP<sub>3</sub> = PhB(CH<sub>2</sub>PPh<sub>2</sub>)<sub>3</sub>; Tp<sup>x</sup> = Hydrotrispyrazolylborate)
作者:M. Ángeles Fuentes、Eleuterio Álvarez、Ana Caballero、Pedro J. Pérez
DOI:10.1021/om201016b
日期:2012.2.13
The novel complexes [(PhBP3)Cu(L)] (PhBP3 = PhB(CH2PPh2)(3), L = PPh3, 1; L = tetrahydrofuran, 2) have been synthesized and spectroscopically and, in the case of 1, structurally characterized. Both complexes undergo dissociation of the PPh3 or THF ligand in solution to deliver the (PhBP3)Cu unit, similar in geometry to and isoelectronic with Tp(x)Cu (Tp(x) = trispyrazolylborate ligand). A complete study of the catalytic properties of 1 has shown that it can be considered as a surrogate of Tp(x)Cu. The study includes (a) olefin cyclopropanation, cyclopropenation, aziridination, halocarbon addition, and radical polymerization, (b) X-H (X = O, N) functionalization by carbene insertion, and (c) furan conversion into dihydropyridines. Since the observed activity is quite comparable to that already described for Tp(x)Cu complexes, this new catalytic system could become an alternative to the latter.
Selective Synthesis of N-Substituted 1,2-Dihydropyridines from Furans by Copper-Induced Concurrent Tandem Catalysis
作者:Manuel R. Fructos、Eleuterio Álvarez、M. Mar Díaz-Requejo、Pedro J. Pérez
DOI:10.1021/ja1006614
日期:2010.4.7
A novel transformation in which mono- or dialkyl-substituted furans are converted into 1,2-dihydropyridines upon reaction with PhI horizontal lineNTs at room temperature is reported. The reaction is catalyzed by complexes of general formula Tp(x)M (M = Cu, Ag) and consists of a one-pot procedure with four consecutive catalytic cycles. Furan aziridination is followed by aziridine ring-opening, transimination