Diastereoselective Nickel-Catalyzed Reductive Aldol Cyclizations Using Diethylzinc as the Stoichiometric Reductant: Scope and Mechanistic Insight
作者:Pekka M. Joensuu、Gordon J. Murray、Euan. A. F. Fordyce、Thomas Luebbers、Hon Wai Lam
DOI:10.1021/ja0775624
日期:2008.6.1
In the presence of diethylzinc as a stoichiometric reductant, Ni(acac) 2 functions as an efficient precatalyst for the reductive aldol cyclization of alpha,beta-unsaturated carbonyl compounds tethered to a ketone electrophile through an amide or an ester linkage. The reactions are tolerant of a wide range of substitution at both alpha,beta-unsaturated carbonyl and ketone components and proceed smoothly
A Protocol for the <i>Ortho</i>-Deuteration of Acidic Aromatic Compounds in D<sub>2</sub>O Catalyzed by Cationic Rh<sup>III</sup>
作者:Alyssa L. Garreau、Hanyang Zhou、Michael C. Young
DOI:10.1021/acs.orglett.9b02618
日期:2019.9.6
catalytically introduce deuterium in synthetically useful yields ortho to a carboxylic acid directing group on arenes typically requires D2 or high catalyst loadings, which makes using these approaches cost prohibitive for large-scale synthesis (equipment and reagent costs respectively). Herein, we present a simplified approach using low catalyst loadings of cationic RhIII and D2O as both deuterium source and solvent
10th international symposium on the synthesis and applications of isotopes and isotopically labelled compounds - poster presentations Session 19, Sunday, June 14 to Thursday, June 18, 2009
Kinetics and Mechanism of the Oxidative Cleavage of Unsaturated Acids by Quinolinium Dichromate
作者:Irona Nongkynrih、Mahendra K. Mahanti
DOI:10.1246/bcsj.67.2320
日期:1994.8
oxidant, and acid concentrations. The mechanistic pathway involves an electrophilic attack of the oxidant on the double bond of the substrate, giving a carbonium-ion intermediate. This is supported by a small inverse kinetic isotope effect (kH/kD = 0.78) at the α-carbon and the value of ρ = −4.0.