Synthesis 2018; 50(24): 4829-4836
DOI: 10.1055/s-0037-1610181
paper
© Georg Thieme Verlag Stuttgart · New York

Divergent Reactivity of Indole-Tethered Ynones with Silver(I) and Gold(I) Catalysts: A Combined Synthetic and Computational Study

John T. R. Liddon
,
James A. Rossi-Ashton
,
Aimee K. Clarke
,
Jason M. Lynam*
,
Richard J. K. Taylor*
,
William P. Unsworth*

This work was conducted using funding from EPSRC (EP/M018601/01, J.T.R.L. and EP/R013748/1, A.K.C.), the University of York (J.A.R.-A., A.K.C., W.P.U.) and the Leverhulme Trust (Early Career Fellowship, ECF-2015-13, W.P.U.).
Further Information

Publication History

Received: 27 March 2018

Accepted after revision: 16 May 2018

Publication Date:
04 July 2018 (online)

Abstract

A combined synthetic and computational (DFT) study has been performed to account for the divergent reactivity of indole-tethered ynones when treated with Ag(I) and Au(I) catalysts. The two catalyst systems deliver spirocyclic indolenines and carbazoles, respectively, from the same precursors, with the reaction outcomes believed to be a result of differences in the rates of a key protodemetalation step. A ring-opening/ring-closing isomerisation process is proposed to enable the interconversion of spirocyclic and C-2 annulated indole intermediates, in contrast to the 1,2-migration mechanism tentatively proposed in previous studies.

Supporting Information

 
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