摘要
A novel and efficient[3+2]annulation of 2-substituted aziridines and N-tosyl cyanamides via a dominoregioselective ring-opening/5-exo-dig cyclization procedure has been developed,allowing the directpreparation of N_(2)-unprotected five-membered cyclic guanidines in good to excellent yields under mildconditions without metals and strong bases.Moreover,the highly biologically interesting urea analoguescould also be conveniently obtained via hydrolysis of the produced guanidines.
基金
support from the Natural Science Foundation of Henan Province(grant no.212300410152)
the Key Scientific and Technological Project of Henan Province(grant no.212102110439)
Henan University of Animal Husbandry and Economy(grant no.2019HNUAHEDF011 and XKYCXJJ2020006)
the Key Scientific Research Project for Colleges and Universities of Henan Province(grant no.22B150005)。
