摘要:Department of Chemistry MassachusettsInstitute of Technology, New Jersey 08543, United States
转自:康龙化成
Electrophilic C(sp2)−H Cyanation with Inorganic Cyanate (OCN−) by PIII/PV=O-Catalyzed Phase Transfer Activation
Shicheng Hu and Alexander T. Radosevich*
Department of Chemistry MassachusettsInstitute of Technology, New Jersey 08543, United States
—Angew. Chem., Int. Ed., 2024,DOI: 10.1002/anie.202409854.
Recommended by Shi Li_MOC
KEYWORDS:cyanation (反应类型), organocatalysis (反应类型),C(sp2)-C(sp) (成键类型), (hetero)arenes(原料), sodium cyanate (原料), cyano arene (产物), PIII/PV=O phosphetane (催化剂), phase transfer activation (其他)
ABSTRACT: Anorganophosphorus-catalyzed method for the direct electrophilic cyanation of C(sp2)−H nucleophiles with sodiumcyanate (NaOCN)is reported. The catalytic deoxyfunctionalization of the OCN− anion is enabled by the useof a small-ring phosphacyclic (phosphetane) catalyst in combination with aterminal hydrosilane O-atom acceptor and amalonate-derived bromenium donor. In situ spectroscopy undersingle-turnover conditions demonstrate that insoluble inorganic cyanate anionis activated by bromide displacement on a bromophosphonium catalytic intermediate to give areactive N-bound isocyanatophosphonium ion, which delivers electrophilic“CN+” equivalents to nucleophilic(hetero)arenes and alkenes with loss of a phosphine oxide. These resultsdemonstrate the feasibility of deoxyfunctionalization of insoluble inorganic salts by PIII/PV=Ocatalyzed phase transfer activation.
Background and this work
Optimization studies
Substrate scope (selected)
ReactionmechanismAlexanderT. Radosevich et al describeda new method of electrophilic cyanation by activation of NaOCN under organophosphorus redox catalysis. The strategy enables direct cyanation ofC(sp2)–H nucleophiles, providing an expedientroute for the synthesis of electron-rich (hetero)aryl nitriles, with severalpharmaceutically relevant examples illustrated. Efforts to broaden the strategyto encompass a wider range of oxyanion substrates and to generalize PIII/PV=O-catalyzedphase transfer activation are undergoing in the laboratory.
来源:新浪财经