Substrates and mechanism

There are also reactions which show stereoselectivity primarily because of mechanism rather than spatial bias of substrate. For instance, the conversion of an olefin to a 1,2-diol by osmium tetroxide mechanistically is a cycloaddition process which is strictly suprafacial. The hydroxylation transform has elements of both substrate and mechanism control, as illustrated by the retrosynthetic conversion of 146 to 147. The validity of the retrosynthetic removal of both... 

The capabilities of thin tin films and tin-based alloys with different metals as active materials for lithium - ion battery negative electrodes are considered. Electrochemical characteristics of such films at different substrates and mechanisms of their functioning are discussed. 

These factors lead to an inferior barrier and a more rapid reduction of the barrier effect. For a good barrier effect, co-extrusion or coating of the substrate, corona discharge, or plasma pretreatment, are, therefore, usually necessary. Vacuum metallization conditions, thermal stress of the substrate, and mechanical stress of the metal layer also play a fundamental role ... 

FIGURE 3.10 In situ cell for mechanical testing. (From Polymer Vol. 36, No. 25, Film substrate and mechanical properties of electrochemically prepared PPy, M. Ghandhi and coworkers, p. 4762. With permission from Elsevier Science Ltd., Oxford, England.)... 

Olken, N.M. and Marietta, M.A. (1993) A°-Methyl-L- arginine functions as an alternate substrate and mechanism-based inhibitor of nitric oxide synthase. Biochemistry, 32,9677-9685. 

Another validation study compared the SimCYP approach to the PJ/K approach, an extended [I]/K approach incorporating fraction metabolised by the cytochrome P450, fm , intestinal availability for CYP3A4 substrates and mechanism based inactivation, and the mechanism-dynamic model of Sim-CYP, Overall, the SimCYP approach showed an improvement over the other two. Moreover, where an interaction > 2-fold existed, the SimCYP approach was able to predict the change in area under the curve for the victim drug in 64% of trials, compared to only 53% and 17% for the [IJ/Kj and extended [i]/K approach, respectively. ... 

Kallstrom, K. Munslow, L Andersson, P. G. Ir-catalysed asymmetric hydrogenation Ligands, substrates and mechanism. Chem. 2006,12,3194—3200. 

Recent achievements of Baeyer-Villiger reaction in homogeneous, heterogeneous and biocatalysis reactions have been reviewed the relation between catalyst substrate and mechanism is clarified for different systems and future development of the... 

Kallstrom K, Munslow I, Andersson P. Ir-Catalysed asymmetric hydrogenation ligands, substrates and mechanism. Chem. Eur. J. 2006 12 3194-3200. 

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