Revisiting Methyl-Halide Elimination Reactions in Hydrazide Based Hypercoordinate Silicon(IV) Complexes

Abstract

A group of hypercoordinate silicon(IV) complexes are synthesized by the reactions of O-silylated N,N-dimethylhydrazides with YSiCl₃ (Y = cyclohexyl and i-Bu). All the complexes are characterized by ¹H, ¹³C, and ²⁹Si-NMR spectroscopy. The influence of steric and electronic behavior of remote substituents and the groups attached to silicon on the methyl halide elimination reactions of these complexes are discussed. The rate of methyl-halide elimination strongly depends on the nucleophile strength (i.e., I⁻ > Br⁻ > Cl⁻) and the remote substituent R (R = Me < t-Bu < Ph).

Keywords:

• hexacoordinate silicon complexes
• pentacoordinate siliconium salts
• methyl halide elimination

Acknowledgments

The authors thank DST-VIT-FIST for NMR spectrometer and SIF-VIT for other facilities.

Funding

This work was supported by the Department of Science and Technology Science and Engineering Research Board (DST-SERB; Ref. No. SR/S1/IC-38/2011). Sannapaneni Janardan and Pothini Suman thank DST for the Project Fellowship and VIT University for the Research Associateship, respectively.