30461-17-7Relevant academic research and scientific papers
Studies on the Mechanism of Transition-Metal-Assisted Sodium Borohydride and Lithium Aluminium Hydride Reductions
Osby, John O.,Heinzman, Stephen W.,Ganem, Bruce
, p. 67 - 72 (1986)
Studies on the course of transition-metal-assisted NaBH4 and LiAlH4 reductions of (1) nitriles, (2) alkenes, and (3) alkyl halides are described. (1) The kinetics of benzonitrile (PhCN) reduction indicate that at high nitrile:catalyst ratios, the rate of reduction is independent of PhCN concentrations.Furthermore, the rate of PhCN reduction exhibits a first-order dependence on NaBH4 concentration, as measured over a fourfold range of BH4(1-) concentration and several half-lives of PhCN.Moreover, when PhCN was reduced with equimolar mixtures of NaBH4 and NaBD4, a significant primary kinetic isotope effect was observed.Rapid complexation of PhCN to be boride surface apparently activates the nitrile group toward rate-determining hydride addition from dissolved, uncoordinated NaBH4. (2) The selective reduction of alkenes by NaBH4-CoCl2 is attributed to adventitious heterogeneous catalytic hydrogenation. (3) The combination of LiAlH4 with CoCl2 forms a black precipitate of cobalt aluminide (CoAl) which was isolated, analyzed by atomic absorption spectroscopy, and shown to play an essential catalytic role in the reduction of alkyl halides.Labeling experiments demonstrate stereochemical randomization by a heterogeneous process involving solvent as the hydrogen donor and LiAlH4 as a co-reductant.A radical mechanism involving halide atom transfer or oxidative addition to the aluminide is proposed.
Secondary Deuterium Kinetic Isotope Effects in the Solvolysis of 4-t-Butylcyclohexyl and Bicyclooctan-3-yl Toluene-p-sulphonates. New Results using 50percent Aqueous Ethanol, Acetic Acid, and 97percent Aqueous Hexafluoropropan-2-ol
Banks, R. Margaret,Maskill, H.,Natarajan, Rajagopalan,Wilson, Alan A.
, p. 427 - 431 (2007/10/02)
Secondary α-deuterium kinetic isotope effects for the solvolysis of cis- and trans-4-t-butylcyclohexyl toluene-p-sulphonates in 50percent aqueous ethanol (1.200 -/+ 0.007 and 1.16 -/+ 0.01 respectively, 44.8 deg), acetic acid (1.172 -/+ 0.004 and 1.13 -/+
