Pyridyl group assisted deprotonation of a methyl group on silicon: Complex induced proximity effect and novel hydroxymethylation

K. Itami, T. Kamei, Koichi Mitsudo, T. Nokami, J. I. Yoshida

Research output: Contribution to journalArticle

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Abstract

A novel methodology for the deprotonation of a methyl group on silicon has been developed. This newly developed α-lithiation protocol is based on the intramolecular pyridyl group coordination to stabilize the α-silyl carbanion together with the inherent silicon α effect. It was found that the deprotonation (t-BuLi/Et2O/-78 °C) occurs with 2-pyridyltrimethylsilane but not with other related silanes such as phenyltrimethylsilane, 3-pyridyltrimethylsilane, and 4-pyridyltrimethylsilane. It seems that this deprotonation proceeded through the agency of the complex-induced proximity effect (CIPE) of a 2-pyridyl group on silicon. 1H NMR analysis of (2-pyridyldimethylsilyl)methyllithium revealed the intramolecular coordination of a pyridyl group to lithium. (2-Pyridyldimethylsilyl)-methyllithium was found to react with chlorosilanes, hydrosilanes, chlorostannanes, bromine, iodine, organic bromides, aldehydes, and ketones in good to excellent yields. The resultant adducts were further oxidized with H2O2/KF to give the corresponding alcohols in excellent yields. Thus, this two-step transformation provides an efficient method for the nucleophilic hydroxymethylation.

Original languageEnglish
Pages (from-to)3970-3976
Number of pages7
JournalJournal of Organic Chemistry
Volume66
Issue number11
DOIs
Publication statusPublished - Jun 1 2001
Externally publishedYes

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Deprotonation
Silicon
Silanes
Bromine
Ketones
Bromides
Lithium
Aldehydes
Iodine
Alcohols
Nuclear magnetic resonance
methyllithium

ASJC Scopus subject areas

  • Organic Chemistry

Cite this

Pyridyl group assisted deprotonation of a methyl group on silicon : Complex induced proximity effect and novel hydroxymethylation. / Itami, K.; Kamei, T.; Mitsudo, Koichi; Nokami, T.; Yoshida, J. I.

In: Journal of Organic Chemistry, Vol. 66, No. 11, 01.06.2001, p. 3970-3976.

Research output: Contribution to journalArticle

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