Abstract
Isothiocyanate 2, obtained from aza-Wittig reaction of iminophosphorane 1 with CS2, reacted with amine to give 2-thioxo-2,3,5,6,7,8-hexahydrobenzothieno[2,3-d]pyrimidin-4(1H)-ones 4 in the presence of sodium ethoxide. S-Alkylation of 4 produced 2-alkylthio-5,6,7,8-tetrahydrobenzothieno[2,3-d]pyrimidin-4(3H)-ones 5 in good yields.
ACKNOWLEDGMENTS
We gratefully acknowledge financial support of this work by the National Natural Science Foundation of China (Project No. 20772041), the Key Project of Chinese Ministry of Education (No. 107082), and the Educational Commission of Hubei Province of China (No. B20092412).