title: Time-Resolved Infrared (TRIR) Studies of Oxycarbonylnitrenes.
abstract: N-Ethyloxycarbonyl-S,S-dibenzothiphene sulfilimine and N-t-butyloxycarbonyl-S,S-dibenzothiphene sulfilimine have been utilized as precursors to ethoxycarbonylnitrene and t-butyloxycarbonylnitrene. B3LYP/6-31G(d) calculations predict triplet ground states for both oxycarbonylnitrenes, albeit by small margins. Triplet ethoxycarbonylnitrene and triplet t-butyloxycarbonylnitrene have been observed following photolysis of these sulfilimine precursors by time-resolved infrared (TRIR) spectroscopy. Kinetic studies show that ethoxycarbonylnitrene reacts with solvents such as acetonitrile and cyclohexane, while t-butyloxycarbonylnitrene undergoes an intramolecular insertion reaction to produce 5,5-dimethyl oxazolidinone. Product analysis following photolysis of N-t-butyloxycarbonyl-S,S-dibenzothiphene sulfilimine confirms that the oxazolidinone is the major product with an estimated yield of 90%. The products from these two nitrenes are derived from the corresponding singlet nitrene, either directly or via thermal repopulation of the singlet from the lower-energy triplet nitrene.
authors.affiliation: Department of Chemistry, Johns Hopkins University , Baltimore, Maryland 21218, United States.
authors.forename: Tyler A
authors.initials: TA
authors.lastname: Chavez
authors.affiliation: Department of Chemistry, Johns Hopkins University , Baltimore, Maryland 21218, United States.
authors.forename: Yonglin
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Department of Chemistry, Johns Hopkins University , Baltimore, Maryland 21218, United States.
authors.forename: John P
authors.initials: JP
authors.lastname: Toscano