R. N. Arias-Ugarte, H. K. Sharma and K. H. Pannell
Related experimental details may be found in the supporting
information.
Conclusions
We have demonstrated an efficient process involving the use of
group 14 organo-metalloid derivatives for performing useful
organic transformations, namely thioamides to amides (using
Ph3SnOH) and amides to thioamides (using Ph3SiSH). The transfor-
mations seem widely applicable and produce good yields,
frequently without the need for solvents, and often removing the
difficult chromatographic purifications often required with the use
of other thionation reagents.[3b]
Figure 3. DMF to DMTF and reverse transformations using Ph3SiSH and
Ph3SnOH.
Acknowledgments
established in the literature, and can be used for further chemistry
but without S–S bond formation.[16] However, the presence
of the amino group facilitates iminium salt formation,
{[Me2N¼CH(SH)]+[Ph3SiO]ꢀ}, as has been well established in other
systems, e.g. [Me2N¼CH2]+[I]ꢀ,[17] and the more closely related
[Me2N¼CHSPh]+Iꢀ.[18] The formation of the iminium salt readily
permits silanol elimination via [Ph3SiO]ꢀ protonation resulting in
thioamide formation. The stannoxythiols or thiostannoxy alcohols
are unreported.
We thank the Welch Foundation, Houston, TX for support of this
research via grant no. AH-0546.
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Experimental
The reagents 1 and 2 were purchased from Gelest Inc., and used as
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DMTF → DMF
A 250 ml round-bottom flask equipped with a stirring bar and reflux
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wileyonlinelibrary.com/journal/aoc
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Appl. Organometal. Chem. 2016, 30, 510–513