Tris(trimethylsilyl)sulfonium and methylbis(trimethylsilyl)sulfonium ions: preparation, NMR spectroscopy, and theoretical studies(1)

GK Prakash; C Bae; Q Wang; G Rasul; GA Olah

doi:10.1021/jo001248+

Tris(trimethylsilyl)sulfonium and methylbis(trimethylsilyl)sulfonium ions: preparation, NMR spectroscopy, and theoretical studies(1)

J Org Chem. 2000 Nov 3;65(22):7646-9. doi: 10.1021/jo001248+.

Authors

GK Prakash¹, C Bae, Q Wang, G Rasul, GA Olah

Affiliation

¹ Donald P. and Katherine B. Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, University Park, Los Angeles, California 90089-1661, USA.

PMID: 11076628
DOI: 10.1021/jo001248+

Abstract

Tris(trimethylsilyl)sulfonium 1 and methylbis(trimethylsilyl)sulfonium 2 ions were prepared as long-lived species by reacting trimethylsilane and trityl tetrakis(pentafluorophenyl)borate (Ph(3)C(+) TPFPB) in the presence of precursor sulfides and characterized by (1)H, (13)C, and (29)Si NMR spectroscopy at -78 degrees C. Attempted preparation of dimethyl(trimethylsilyl)sulfonium ion under similar conditions failed as a result of the formation of the more stabilized trimethylsulfonium ion. Structures, and (13)C and (29)Si NMR chemical shifts were calculated by density functional theory (DFT)/IGLO methods. The calculated results agree well with the experimental data.