1353883-27-8Relevant articles and documents
A detailed study of the intramolecular hydroamination of N-(ortho-alkynyl)aryl-N′-substituted trifluoroacetamidines and bromodifluoroacetamidines
Zhu, Jiangtao,Xie, Haibo,Chen, Zixian,Li, Shan,Wu, Yongming
experimental part, p. 516 - 523 (2012/01/15)
The intramolecular hydroamination of N-(ortho-alkynyl)aryl-N′- substituted trifluoroacetamidines and bromodifluoroacetamidines is studied in detail. When the substituents on the alkyne fragment are aryl and alkyl groups, 5-endo-dig cyclization occurs utilizing NaAuCl4·2H 2O as a catalyst, while 6-exo-dig cyclization proceeds in the presence of K2CO3 as a base. Interestingly, the indole derivatives are afforded with good regioselectivity via a 5-endo-dig pathway catalyzed by Cu(OAc)2 when ortho-ethynyl appears on the aryl substituent of the amidine. The electrophilic cyclization of the amidines also shows good regioselectivity under the I2/NaHCO3 system. At the end, a facile cascade synthesis of fluorinated quinazolones is described via hydroamination/ozonolysis from the corresponding amidine.