Ni-Catalyzed Regioselective 1,2-Dicarbofunctionalization of Olefins by Intercepting Heck Intermediates as Imine-Stabilized Transient Metallacycles
作者:Bijay Shrestha、Prakash Basnet、Roshan K. Dhungana、Shekhar KC、Surendra Thapa、Jeremiah M. Sears、Ramesh Giri
DOI:10.1021/jacs.7b06340
日期:2017.8.9
in styrenes by intercepting Heck C(sp3)-NiX intermediates with arylzinc reagents. This approach utilizes a readily removable imine as a coordinating group that plays a dual role of intercepting oxidative addition species derived from aryl halides and triflates to promote Heck carbometalation and stabilizing the Heck C(sp3)-NiX intermediates as transient metallacycles to suppress β-hydride elimination
Ni-catalysed regioselective 1,2-diarylation of unactivated olefins by stabilizing Heck intermediates as pyridylsilyl-coordinated transient metallacycles
作者:Surendra Thapa、Roshan K. Dhungana、Rajani Thapa Magar、Bijay Shrestha、Shekhar KC、Ramesh Giri
DOI:10.1039/c7sc04351a
日期:——
Ni-catalysed diarylation of vinylpyridylsilanes with arylzinc reagents and aryl halides is reported by stabilizing Heck intermediates as pyridylsilyl-coordinated transient metallacycles.
Carbonylative homocoupling of arylzinc compounds 1 using 1 atm of CO and 1,2-dibromoethane as an oxidant was achieved in the presence of Rh-dppf catalyst, affording symmetrical diaryl ketones in good yields. Under similar conditions, Pd or Ni catalysts induced oxidative homo coupling of 1 to yield biaryls instead. The beneficial catalysis by Rh in the carbonylation was presumed to stem from the facility by which the migration of the aryl ligand to CO at the Rh3+ intermediate occurred.
Transition-Metal-Free Carboxylation of Organozinc Reagents Using CO<sub>2</sub> in DMF Solvent
作者:Koji Kobayashi、Yoshinori Kondo
DOI:10.1021/ol900528h
日期:2009.5.7
An efficient process for the carboxylation of functionalized organozinc reagents with CO2 under transition-metal-free conditions was developed by employing DMF solvent in the presence of LICl.
Cu-Catalyzed Cyclization/Coupling of Alkenyl Aldimines with Arylzinc Reagents: Access to Indole-3-diarylmethanes
作者:Rishi R. Sapkota、Raj Kumar Tak、Vivek Aryal、Doleshwar Niroula、Nicholas C. Secosky、Roshan K. Dhungana、Ramesh Giri