The aza-Wittig reactions of iminophosphorane 3 with aromatic isocyanates generated carbodiimides 4. which were reacted with alkylamines under mild conditions to give a series of 2-(alkylamino)-5. 6-dimethylthieno[2. 3-d]pyrimidin-4(3H)-ones 6 and 8 in satisfactory yield. https://www.ngetikin.com/