Silylation of <i>N,O</i>-Diacylhydroxylamines: NMR Spectra
and Structure of the Products
Jan Schraml
Jaromír Mindl
Jana Roithová
Vratislav Blechta
Jan Sýkora
Ludmila Soukupová
Jindřich Karban
Milena Bártlová
Otto Exner
10.1021/om030684u.s001
https://acs.figshare.com/articles/journal_contribution/Silylation_of_i_N_O_i_Diacylhydroxylamines_NMR_Spectra_and_Structure_of_the_Products/3341722
Silylation of <i>N,O</i>-diacylhydroxylamines with <i>N</i>-(<i>tert</i>-butyldimethylsilyl)-<i>N</i>-methyltrifluoroacetamide produces only O-silylated products and no N-silylated derivative. Steric
interactions of the substituents on the nitrogen atom with the O−N oxygen atom control
the configuration on the CN bond in the product: a <i>Z </i>isomer is formed almost exclusively
from <i>N</i>-benzoylhydroxylamines, and a mixture of <i>E</i> and <i>Z</i> isomers is produced from <i>N</i>-acetyl
derivatives. The relative stability of all isomers in various conformations was confirmed by
calculations at the B3LYP/6-31G(d,p) level. The <i>tert</i>-butyldimethylsilyl derivatives have been
fully characterized by their <sup>1</sup>H, <sup>13</sup>C, <sup>15</sup>N, and <sup>29</sup>Si NMR spectra.
2004-04-26 00:00:00
calculation
stability
diacylhydroxylamine
Z isomer
29 Si NMR spectra
configuration
acetyl derivatives
Products Silylation
mixture
butyldimethylsilyl derivatives
13 C
B 3LYP level
Spectra
Steric interactions
conformation
1 H
substituent
Z isomers
methyltrifluoroacetamide
benzoylhydroxylamine
Diacylhydroxylamine
nitrogen atom
tert
15 N
bond