Copper-catalysed intramolecular O-arylation of aryl chlorides and bromides: a straightforward approach to benzo[d]oxazoles in water
摘要:
A general, efficient and more sustainable protocol for the copper-catalysed intramolecular O-arylation of o'- haloanilides leading to the benzo[d]oxazole core is reported. Remarkably, the optimised conditions allowed for the use of inexpensive and easily available aryl chlorides as arylating agents. Moreover, all reactions were carried out employing exclusively water as the solvent, rendering the methodology presented herein highly valuable from both environmental and economic points of view. (c) 2007 Elsevier Ltd. All rights reserved.
Copper-catalysed intramolecular O-arylation of aryl chlorides and bromides: a straightforward approach to benzo[d]oxazoles in water
摘要:
A general, efficient and more sustainable protocol for the copper-catalysed intramolecular O-arylation of o'- haloanilides leading to the benzo[d]oxazole core is reported. Remarkably, the optimised conditions allowed for the use of inexpensive and easily available aryl chlorides as arylating agents. Moreover, all reactions were carried out employing exclusively water as the solvent, rendering the methodology presented herein highly valuable from both environmental and economic points of view. (c) 2007 Elsevier Ltd. All rights reserved.
A convenient enantioselective synthesis of 3-asymmetrically substituted oxindoles is reported. Compound (2) prepared by radical cyclisation of (1) was used for the synthesis of racemic and enantiomerically pure 3-asymmetrically substituted oxindoles. Desulfurisation of (2) using Raney Ni yielded the racemate (5). Addition of (S)-1-phenylethanol to compound (2) yielded the diastereoisomer (21) the structure of which was determined using X-ray crystallography. Using a sequence of steps (21) was converted to the enantiomer (8). The enantiomer (9) was similarly prepared from (2) using (R)-1-phenylethanol. (C) 2011 Elsevier Ltd. All rights reserved.
Barbieri, Cristina Lea; Ceraulo, Leopoldo; Maria, Paolo De, Heterocycles, 1991, vol. 32, # 5, p. 975 - 984
作者:Barbieri, Cristina Lea、Ceraulo, Leopoldo、Maria, Paolo De、Fontana, Antonella、Spinelli, Domenico、Zuppiroli, Luca
DOI:——
日期:——
Copper-catalysed intramolecular O-arylation of aryl chlorides and bromides: a straightforward approach to benzo[d]oxazoles in water
A general, efficient and more sustainable protocol for the copper-catalysed intramolecular O-arylation of o'- haloanilides leading to the benzo[d]oxazole core is reported. Remarkably, the optimised conditions allowed for the use of inexpensive and easily available aryl chlorides as arylating agents. Moreover, all reactions were carried out employing exclusively water as the solvent, rendering the methodology presented herein highly valuable from both environmental and economic points of view. (c) 2007 Elsevier Ltd. All rights reserved.