Sulfamoyl nitrenes: singlet or triplet ground state
Yan Lu‡a, Hongmin Li‡a, Manabu Abe b, Didier Be´gue´c, Huabin Wan a, Guohai Deng a, Jian Xu a, Kun Liud and Xiaoqing Zeng *a（曾小庆）
a College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou 215123, China.
b Department of Chemistry, Graduate School of Science, Hiroshima University, 1-3-1 Kagamiyama, Higashi-Hiroshima Hiroshima 739-8526, Japan
c Institut Pluridisciplinaire de Recherche sur l’Environnement et les Mate´riaux, Universite´de Pau et des Pays de l’Adour, Pau 64000, France
d College of Chemistry, Tianjin Normal University, Tianjin, 300387, China
‡ These authors contributed equally
Chem. Commun., 2018, 54, 6136--6139
Unlike a triplet spin-state for alkyl- and aryl-sulfonylnitrenes, theoretical computations suggest a closed-shell singlet (CSS) ground state for simple sulfamoylnitrenes R2NS(O)2–N (R = H and Me) due to intramolecular N⋯N interactions. Experimentally, both sulfamoylnitrenes, generated in the laser photolysis of the corresponding azides, were isolated in the triplet state as evidenced by EPR (5 K) and IR (3 K) spectroscopy. The formation of the higher-energy triplet state is reasonably explained by a change of spin from the initially generated CSS state through a low-energy minimum energy crossing point (MECP).