Background: Substituted-silyl thiophene carboxylates are important intermediates
for the synthesis of substituted-silyl thiophene carboxamides which have
been found to show high biological activities.
Methods: Using α-mercapto ketones and 3-(substituted-silyl)propiolates as raw materials,
2-(substituted-silyl)thiophene-3-carboxylates could be synthesized smoothly
via cycloaddition reaction catalyzed by potassium tert-butoxide.
Results: A small library of target compounds was prepared under optimized reaction
conditions in moderate to good yields. The reaction mechanism has been proposed.
Conclusion: Potassium tert-butoxide is an environmentally friendly and efficient catalyst
for the cycloaddition reaction of α -mercapto ketones and 3-(substituted-silyl)propiolates. This
methodology provides ready access to 2-(substituted-silyl)thiophene-3-carboxylic acids which can be
serve as the raw materials of 2-(substituted-silyl)thiophene-3-carboxamide and other pharmaceutically