Synthesis 2021; 53(11): 1989-1999
DOI: 10.1055/s-0040-1706658
paper

Complementary and Regioselective Synthesis of Isomeric 3-[Isoxazol-3(or 5)-yl]indoles from β-Ethylthio-β-indolyl-α,β-unsaturated Ketones

Haifeng Yu
a   College of Chemistry, Baicheng Normal University, Baicheng, Jilin 137000, China
,
Kehua Wang
b   School of Chemistry and Life Science, Anshan Normal University, Anshan, Liaoning, 114007, China
,
Xue Zhang
a   College of Chemistry, Baicheng Normal University, Baicheng, Jilin 137000, China
,
Wenju Wang
a   College of Chemistry, Baicheng Normal University, Baicheng, Jilin 137000, China
› Author Affiliations
This work was supported by the Foundation of Education Department of Jilin Province [JJKH20200001KJ, JJKH2016037KJ].


Abstract

A simple and efficient method for the complementary and regioselective synthesis of isomeric 3-(isoxazol-5-yl)indoles and 3-(isoxazol-3-yl)indoles has been developed by the regioselective cyclocondensation reaction of β-ethylthio-β-indolyl-α,β-unsaturated ketones and hydroxylamine hydrochloride. It was found that the cyclocondensation reaction in the presence of excess NaOEt in refluxing EtOH gives 3-(isoxazol-5-yl)indoles in good yields, whereas using NaOAc in boiling AcOH gives 3-(isoxazol-3-yl)indoles in good yields.

Supporting Information



Publication History

Received: 01 September 2020

Accepted after revision: 02 December 2020

Article published online:
11 January 2021

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