126567-44-0Relevant academic research and scientific papers
Benzimidazole Condensed Ring Systems. 5. Studies on the Synthesis of Pyrimidobenzimidazole-1,3(2H,5H)-diones
Badawey, El-Sayed A.M.,Rida, Samia M.,Soliman, Farid S.G.,Kappe, Thomas
, p. 1401 - 1404 (2007/10/02)
The reaction of ethyl 1H-benzimidazole-2-acetate (1) with methyl or ethyl isocyanates 2a,b resulted in excellent yields of the respective 2-methyl- or 2-ethylpyrimidobenzimidazole-1,3(2H,5H)-diones 3a,b, while the reaction of 1 with phenyl isocyanate (2c) gave, unexpectedly, ethyl 2-(1-phenylcarbamoyl-1H,3H-benzimidazol-2-ylidene)-2-phenylcarbamoylacetate (4).Alkylation of 3 with trimethyl or triethyl phosphates 5a,b led to the 5-methyl or 5-ethyl derivatives 6a-d.Chlorination of 6 with sulfuryl chloride afforded the 4-chloro derivatives 7a-d.
