Cyclisation reactions of some 3-nitrosoimidazo[1,2-a]-pyridines and-pyrimidines. Ring-opening/ring-closure reactions with triethyl phosphite: reassignment by X-ray crystal structure and nuclear magnetic resonance
作者:Jean C. Teulade、Roger Escale、Henry Viols、Jean P. Chapat、Gérard Grassy、Alain Carpy、Jean M. Léger
DOI:10.1039/p19830002663
日期:——
Deoxygenation of 3-nitroso-2-phenylimidazo[1,2-a]-pyridines and -pyrimidines with triethyl phosphite does not lead to the products described in the literature as pyrido- and pyrimido-imidazoindoles (3) and (4), but to the open-chain derivatives, N-(2-pyridyl)- and N-(2-pyrimidyl)-benzimidoyl cyanides (5) and (6). X-Ray crystallographic analysis confirms the structure of (5a): orthorhombic system with
3-亚硝基-2-苯基咪唑并[1,2- a ]-吡啶和-嘧啶与亚磷酸三乙酯的脱氧作用不会导致文献中所述的产物为吡啶基和嘧啶基-咪唑并吲哚(3)和(4),但开链衍生物N-(2-吡啶基)-和N-(2-嘧啶基)-苯并亚甲基氰化物(5)和(6)。X射线晶体学分析证实了(5a)的结构:正交晶系,a = 24.377(6),b = 11.729(3),c = 7.534(2)Å,空间群Pbca,Z = 8,d = 1.27 g /厘米3,- [R= 0.061。用化合物(5)和(6)的亚磷酸三乙酯热闭环产生3-氨基-2-苯基咪唑并[1,2- a ]-吡啶和-嘧啶(8)和(9)。