1College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, P. R. China
2Institut für Chemie und Biochemie, Freie Universität Berlin, Berlin, Germany
The stepwise decomposition of carbonyl diisocyanate, OC(NCO)2, has been studied by using IR spectroscopy in solid argon matrices at 16K. Upon irradiation with an ArF laser (λ=193nm), carbonyl diisocyanate split off CO and furnished a new carbonyl nitrene, OCNC(O)N, in its triplet ground state. Two conformers of the nitrene,synandanti, that were derived from the two conformers of OC(NCO)2(62%syn–synand 38%syn–anti) were identified and characterized by combining IR spectroscopy and quantum chemical calculations. Subsequent irradiation with visible light (λ>395nm) caused the Curtius rearrangement of the nitrene into OCNNCO. In addition to the expected decomposition products, N2and CO, further photolysis of OCNNCO with the ArF laser yielded NOCN, through a diazomethanone (NNCO) intermediate. To further validate our proposed reaction mechanism, ArF-laser photolysis of the closely related NNNNCO andcyclo-N2CO in solid argon matrices were also studied. The observations of NOCN and insitu CO-trapped product OCNNCO provided indirect evidence to support the initial generation of NNCO as a common intermediate during the laser photolysis of OCNNCO, NNNNCO, andcyclo-N2CO.
链接：http://onlinelibrary.wiley.com/doi/10.1002/asia.201601073/abstrac
