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29Si13C spin–spin couplings over an SiOCsp3 link

✍ Scribed by Jan Sýkora; Vratislav Blechta; Ludmila Soukupová; Jan Schraml

Publisher
John Wiley and Sons
Year
2008
Tongue
English
Weight
160 KB
Volume
46
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

^29^Si^13^C spin–spin couplings over one, two, and three bonds as well as other NMR parameters [δ(^29^Si), δ(^13^C), δ(^1^H), ^1^J(^13^C^1^H), and ^2^J(^29^SiC^1^H)] were calculated and measured for a series of trimethylsilylated alcohols of the types Me~3~SiO(CH~2~)~n~CH~3~ and Me~3~SiOCH~3−n~R~n~(n = 03; R = Me, Ph, or Vi). The signs of the coupling constants determined for selected compounds can likely be extended to all such compounds, as supported by theoretical calculations. Similar to couplings between other pairs of nuclei, the 2‐bond and 3‐bond ^29^SiO^13^C couplings are of opposite signs (^2^J > 0 and ^3^J < 0), and their relative magnitudes depend on the extent of branching at the α‐carbon. Copyright © 2008 John Wiley & Sons, Ltd.

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