7-Chloroquinoline: a versatile intermediate for the synthesis of 7-substituted quinolines
摘要:
A practical synthesis of 7-mono-substituted quinolines has been achieved. Selective reduction of the inexpensive commercial reagent 4,7-dichloroquinoline affords 7-chloroquinoline, which has been converted into more complex 7-mono-substituted quinolines through a series of Pd-catalyzed cross coupling reactions. These studies include the first examples of Suzuki reactions for the preparation of 7-mono-substituted quinolines as well as the first application of the Sonagashira reaction for the synthesis of 7-substituted quinolines. This strategy has been extended to the preparation of 2,7-di-substituted quinolines. (C) 2009 Elsevier Ltd. All rights reserved.
protonolysis of the Ir–C(vinyl) bond. Instead, mechanistic data are consistent with an anion-involved alcoholysis pathway involving ionization of (NCP)IrCl(vinyl) via EtOH-for-Cl substitution and reversible protonation of Cl– ion with an Ir(III)-bound EtOH, followed by β-H elimination of the ethoxy ligand and C(vinyl)–H reductive elimination. The use of an amine is key to the monohydride mechanism by promoting
7-Chloroquinoline: a versatile intermediate for the synthesis of 7-substituted quinolines
作者:Joshua J. Hirner、Michael J. Zacuto
DOI:10.1016/j.tetlet.2009.06.077
日期:2009.9
A practical synthesis of 7-mono-substituted quinolines has been achieved. Selective reduction of the inexpensive commercial reagent 4,7-dichloroquinoline affords 7-chloroquinoline, which has been converted into more complex 7-mono-substituted quinolines through a series of Pd-catalyzed cross coupling reactions. These studies include the first examples of Suzuki reactions for the preparation of 7-mono-substituted quinolines as well as the first application of the Sonagashira reaction for the synthesis of 7-substituted quinolines. This strategy has been extended to the preparation of 2,7-di-substituted quinolines. (C) 2009 Elsevier Ltd. All rights reserved.