Synlett

New cobalt-catalyzed cross-coupling reactions of heterocyclic chlorides with aryl and heteroaryl magnesium halides

TJ Korn, G Cahiez, P Knochel

Index: Korn, Tobias J.; Cahiez, Gerard; Knochel, Paul Synlett, 2003 , # 12 p. 1892 - 1894

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Citation Number: 22

Abstract

Preliminary experiments show that among various solvents like THF, DME, toluene or diethyl ether, the use of diethyl ether gives the best results. The choice of the cobalt(II) salt as catalyst was also important. Using the reaction of 2-chloroquinoline (1a) with PhMgCl as a test reaction, we have found that the cross-coupling reaction using CoBr 2 or CoI 2 as catalysts (5 mol%) in ether are fast at -40 °C leading to the desired product 3a in 76-80% yield. A ...