Synthesis 2016; 48(23): 4260-4268
DOI: 10.1055/s-0035-1562611
paper
© Georg Thieme Verlag Stuttgart · New York

Transition-Metal-Free Terminal Alkyne Addition to Isatins

Kalyan Dhara
Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India   Email: ocjd@iacs.res.in
,
Ajoy Kapat
Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India   Email: ocjd@iacs.res.in
,
Tridev Ghosh
Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India   Email: ocjd@iacs.res.in
,
Jyotirmayee Dash*
Department of Organic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700032, India   Email: ocjd@iacs.res.in
› Author Affiliations
Further Information

Publication History

Received: 20 May 2016

Accepted after revision: 11 July 2016

Publication Date:
24 August 2016 (online)


Abstract

A ‘direct’ alkynylation of isatins, which uses potassium tert-butoxide to provide the desired 3-hydroxy-3-ethynyl-2-oxindoles in good to high yields, is reported. This protocol proceeds smoothly for both electron-rich and electron-deficient alkynes in comparable reaction rates and does not require any specially design ligand or expensive transition-metal catalysts.

Supporting Information

 
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