Lithiations of 1-trialkylsilylpyrroles: N to C silyl group rearrangement
- 1 January 1982
- journal article
- research article
- Published by Royal Society of Chemistry (RSC) in Journal of the Chemical Society, Perkin Transactions 1
- p. 1833-1836
- https://doi.org/10.1039/p19820001833
Abstract
The sites of metallation with alkyl-lithium reagents of 1-trimethylsilyl- and 1-triethylsilyl-pyrroles have been explored under a variety of conditions. With short reaction times, BunLi reacts with 1-trimethylsilylpyrrole in hexane predominantly at the 2-position though with ButLi in pentane the unusual 3-metallated product is preferred. During prolonged reaction of 1-trimethylsilyl- and 1-triethylsilyl-pyrroles with ButLi, the 2-monolithio- and the 2,4- and 2,5-dilithio-intermediates are formed, in which, unexpectedly, the silyl groups migrate to the pyrrole 2-position. Under conditions favouring enhanced ionicity, BunLi cleaves the N–SiMe3 bond in preference to ring metallation.Keywords
This publication has 0 references indexed in Scilit: