A tetra-coordinate, square planar germanium(IV) cation [(TPFC)Ge](+) (TPFC = tris(pentafluorophenyl)corrole) was synthesized quantitatively by the reaction of (TPFC)Ge-H with [Ph3C](+)[B(C6F5)4](¯). The highly reactive [(TPFC)Ge](+) cation reacted with benzene to form phenyl complex (TPFC)Ge-C6H5 through an electrophilic pathway. The key intermediate, a σ-type germylium-benzene adduct, [(TPFC)Ge(η(1)-C6H6)](+), was isolated and characterized by single-crystal X-ray diffraction.
View Article and Find Full Text PDFA nickel(II) porphyrin Ni-P (P=porphyrin) bearing four meso-C6 F5 groups to improve solubility and activity was used to explore different hydrogen-evolution-reaction (HER) mechanisms. Doubly reduced Ni-P ([Ni-P](2-) ) was involved in H2 production from acetic acid, whereas a singly reduced species ([Ni-P](-) ) initiated HER with stronger trifluoroacetic acid (TFA). High activity and stability of Ni-P were observed in catalysis, with a remarkable ic /ip value of 77 with TFA at a scan rate of 100 mV s(-1) and 20 °C.
View Article and Find Full Text PDF(TPFC)Ge(TEMPO) (1, TPFC = tris(pentafluorophenyl)corrole, TEMPO(•) = (2,2,6,6-tetramethylpiperidin-1-yl)oxyl) shows high reactivity toward E-H (E = N, O) bond cleavage in R1R2NH (R1R2 = HH, (n)PrH, (i)Pr2, Et2, PhH) and ROH (R = H, CH3) under visible light irradiation. Electron paramagnetic resonance (EPR) analyses together with the density functional theory (DFT) calculations reveal the E-H bond activation by [(TPFC)Ge](0)(2)/TEMPO(•) radical pair, generated by photocleavage of the labile Ge-O bond in compound 1, involving two sequential steps: (i) coordination of substrates to [(TPFC)Ge](0) and (ii) E-H bond cleavage induced by TEMPO(•) through proton coupled electron transfer (PCET).
View Article and Find Full Text PDFCatalytic hydrolysis of silanes mediated by chlorodicarbonylrhodium(I) dimer [RhCl(CO)2]2 to produce silanols and dihydrogen efficiently under mild conditions is reported. Second-order kinetics and activation parameters are determined by monitoring the rate of dihydrogen evolution. The mixing of [RhCl(CO)2]2 and HSiCl3 results in rapid formation of a rhodium silane σ complex.
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