St Petersburg State University, Institute of Chemistry, 7/9 Universitetskaya nab., St Petersburg, 199034, Russia.
Org Biomol Chem. 2020 Mar 25;18(12):2283-2296. doi: 10.1039/d0ob00206b.
A one-pot method was developed for the preparation of 2H-azirine-2-carbonylbenzotriazoles, formed by the reaction of benzotriazole with 2H-azirine-2-carbonyl chlorides, which were generated by the Fe(ii)-catalyzed isomerization of 5-chloroisoxazoles. The Co(ii)-catalyzed reaction of 2H-azirine-2-carbonylbenzotriazoles with 1,3-diketones provides 2-((benzotriazol-1-yl)carbonyl)pyrroles in moderate to good yields. Base-promoted annulations of 2-((benzotriazol-1-yl)carbonyl)pyrroles with aldehydes, ketones, isocyanates and isothiocyanates afford various substituted pyrrolo[1,2-c]oxazole and 1H-pyrrolo[1,2-c]imidazole derivatives in moderate to high yields. The 6-acyl group of these adducts can be removed by triflic acid, giving further new pyrrolo-fused O- and N-heterocycles, such as 6-unsubstituted pyrrolo[1,2-c]oxazol-1(3H)-one and 1H-pyrrolo[1,2-c]imidazole-1,3(2H)-dione, while the 6-acetyl substituent of 1H-pyrrolo[1,2-c]imidazole-1,3(2H)-dione, when treated with POCl3/pyridine, is transformed into the 6-ethynyl substituent.
一种一锅法被开发用于制备 2H-氮杂环丁-2-羰酰基苯并三唑，该方法是通过苯并三唑与 2H-氮杂环丁-2-羰酰氯的反应得到的，后者是由 Fe(ii)催化的 5-氯异恶唑的异构化生成的。Co(ii)催化的 2H-氮杂环丁-2-羰酰基苯并三唑与 1,3-二酮的反应以中等至良好的收率提供 2-((苯并三唑-1-基)羰基)吡咯。2-((苯并三唑-1-基)羰基)吡咯与醛、酮、异氰酸酯和异硫氰酸酯的碱基促进的环合以中等至较高的收率提供各种取代的吡咯并[1,2-c]恶唑和 1H-吡咯并[1,2-c]咪唑衍生物。这些加合物的 6-酰基可以被三氟甲磺酸除去，得到进一步的新的吡咯稠合的 O-和 N-杂环，如 6-未取代的吡咯并[1,2-c]恶唑-1(3H)-酮和 1H-吡咯并[1,2-c]咪唑-1,3(2H)-二酮，而 1H-吡咯并[1,2-c]咪唑-1,3(2H)-二酮的 6-乙酰基取代基，当用 POCl3/吡啶处理时，转化为 6-乙炔基取代基。
