Influence of trimethylsilyl substituents on primary C-O bond lengths at the β-position: Results from low-temperature x-ray structural studies

Abstract

The β-trimethylsilyl substituent in 2-trimethylsilylethyl p-nitrobenzoate (12b) and 2-trimethylsilylethyl 2,4-dinitrobenzenesulfenate (12c) leads to significant lengthening of the C(alkyl)-O(ester) bond. Lengthening of the Si-CH2 distance in the more electronegative ester (12c) relative to (12b) is also observed. These structural effects are consistent with the presence of σ C-Si-σ* C-O interactions.