Synthesis and Dimroth Rearrangement of 6-Cyano-l,2,4-triazolo- [4,3-a]pyrimidin-5- and 7-ones. A Novel Alkylation with Orthoesters and a New Participation of the Cyano Group in the Rearrangement
作者:E. S. H. El Ashry、Y. El Kilany、N. Rashed、A. Mousaad、H. Assafir
DOI:10.1515/znb-1998-1017
日期:1998.10.1
4-dihydropyrimidin-4-one (6) with one carbon inserting agents have been confirmed to be of the 1,2,4-triazolo[4,3-a]pyrimidin- 5(8H)-ones type and not the respective 7-ones, by comparing their alkylated derivatives 10a, 11a, 27 and 28 with the product from the cyclization of the 3-methyl and 3-benzyl derivatives of 6. A novel alkylation process was found when triethyl orthoformate was used as a cyclizing
摘要 5-cyano-2-hydrazino-6-phenyl-3,4-dihydropyrimidin-4-one (6) 与一个碳插入剂的环化产物已被证实为 1,2,4-triazolo [4 , 3-a] 嘧啶- 5 (8H) -ones 类型而不是各自的 7-ones,通过将它们的烷基化衍生物 10a、11a、27 和 28 与 3-甲基和 3-苄基衍生物环化的产物进行比较6. 当使用原甲酸三乙酯作为环化剂时,发现了一种新的烷基化过程。8、14、15、24、34 和 36 与 2% 乙醇 KOH 的 Dimroth 重排分别得到各自的三唑并 [1,5-a] 嘧啶酮 13、18、19、25、38 和 40。使用 10% 乙醇 KOH 导致氰基参与重排,从而 8a 得到 7-亚氨基-5-苯基-1,2,4-三唑并 [1,5-a] 嘧啶 22