Abstract
O -Ethyl thioformate has been synthesized
from triethylorthoformate and hydrogen sulfide gas using
a Brønstead acid catalyst. The product can be isolated
as a neat liquid in 83% overall yield. Both the crude and
purified thiolate can be used to thioformylate a variety of amines
in good to excellent yields.
Key words
hydrogen sulfide - thioformate - sulfur - amines - condensation
References and Notes
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Hydrogen sulfide was charged to the
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<A NAME="RS09109ST-21">21 </A>
O -Ethyl
thioformate purified by distillation typically contains 3 wt% ethyl
formate as an impurity. The presence of ethyl formate does not affect
the thioformylation chemistry described herein.
<A NAME="RS09109ST-22">22 </A>
When stored under nitrogen, 1 is stable for 1 month at r.t. and for
5 months at -20 ˚C. See Supporting Information.
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Details available in Supporting Information.
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