Reference of 29841-69-8, Catalysts are substances that increase the reaction rate of a chemical reaction without being consumed in the process. 29841-69-8, Name is (1S,2S)-(-)-1,2-Diphenylethylenediamine, molecular formula is C14H16N2. In a Article£¬once mentioned of 29841-69-8
Chiral phosphoramide-catalyzed aldol additions of ketone trichlorosilyl enolates. Mechanistic aspects
The mechanism of the catalytic, enantioselective addition of trichlorosilyl enolates to aldehydes has been investigated. Kinetic studies using ReactIR and rapid injection NMR (RINMR) spectroscopy have confirmed the simultaneous operation of dual mechanistic pathways involving either one or two phosphoramides bound to a siliconium ion organizational center. This mechanistic dichotomy was initially postulated on the basis of catalyst loading studies and nonlinear effects studies. This duality explains the difference in reactivity and stereoselectivity of various classes of phosphoramides. Determination of Arrhenius activation parameters revealed that aldol addition occurs through the reversible albeit unfavorable formation of an activated complex, and natural-abundance 13C NMR kinetic isotope effect (KIE) studies have determined that the turnover limiting step is the aldol addition. A thorough examination of a range of phosphoramides has established empirical structure-activity selectivity relationships. In addition, the effects of catalyst loading, rate of addition, solvents, and additives have been studied and together allow the formulation of a unified mechanistic picture for the aldol addition.
Sometimes chemists are able to propose two or more mechanisms that are consistent with the available data. Reference of 29841-69-8, If a proposed mechanism predicts the wrong experimental rate law, however, the mechanism must be incorrect.Welcome to check out more blogs about 29841-69-8, in my other articles.
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Metal catalyst and ligand design,
Ligand Template Strategies for Catalyst Encapsulation – NCBI