A novel protocol for the synthesis of α-aryl nitriles has been successfully achieved via a copper-catalyzed cyanation of N-tosylhydrazones employing thiocyanate as the source of cyanide. The features of this method include a convenient operation, readily available substrates, low-toxicity thiocyanate salts, and a broad substrate scope.
<i>Ex situ</i> generation of stoichiometric HCN and its application in the Pd-catalysed cyanation of aryl bromides: evidence for a transmetallation step between two oxidative addition Pd-complexes
作者:Steffan K. Kristensen、Espen Z. Eikeland、Esben Taarning、Anders T. Lindhardt、Troels Skrydstrup
DOI:10.1039/c7sc03912c
日期:——
methodology was also suitable for the synthesis of 13C-labelled benzonitriles with ex situ generated 13C-hydrogen cyanide. Stoichiometric studies with the metal complexes were undertaken to delineate the mechanism for this catalytictransformation. Treatment of Pd(P(tBu)3)2 with H13CN in THF provided two Pd-hydride complexes, (P(tBu)3)2Pd(H)(13CN), and [(P(tBu)3)Pd(H)]2Pd(13CN)4, both of which were isolated
Nickel-Catalyzed Markovnikov Transfer Hydrocyanation in the Absence of Lewis Acid
作者:Nils L. Frye、Anup Bhunia、Armido Studer
DOI:10.1021/acs.orglett.0c01454
日期:2020.6.5
Hydrocyanation in the absence of toxic HCN gas is highly desirable. Addressing that challenge, transition-metal-catalyzed transfer hydrocyanation using safe HCN precursors has been developed, but these reagents generally require a Lewis acid for activation, and the control of regioselectivity often remains problematic. In this Letter, a Ni-catalyzed highly Markovnikov-selective transfer hydrocyanation
Activation of Alcohols with Carbon Dioxide: Intermolecular Allylation of Weakly Acidic Pronucleophiles
作者:Simon B. Lang、Theresa M. Locascio、Jon A. Tunge
DOI:10.1021/ol502023d
日期:2014.8.15
coupling of allyl alcohols with nitroalkanes, nitriles, and aldehydes using catalytic Pd(PPh3)4 has been accomplished viaactivation of C–OH bonds with CO2. The in situ formation of carbonates from alcohols and CO2 facilitates oxidativeaddition to Pd to form reactive π-allylpalladium intermediates. In addition, the formation of a strong baseactivates nucleophiles toward the reaction with the π-allylpalladium
Amination at the β-position of 2-arylpropionitriles through catalytic dehydrogenation occurred by using [PdCl2(PMe3)2] catalyst and bromobenzene. This is the first catalytic reaction involving the direct dehydrogenation of saturated nitriles.