New mechanisms centered on reactive intermediates: Examples from diazirine and carbene chemistry*
Robert A. Moss, Jingzhi Tian, Gaosheng Chu, Ronald R. Sauers, and Karsten Krogh-Jespersen
Department of Chemistry and Chemical Biology, Rutgers, The State University of New Jersey, New Brunswick, NJ 08903, USA
Abstract: Laser flash photolysis (LFP) of appropriate diazirine precursors afforded the UV spectra of methylchlorocarbene, benzylchlorocarbene, cyclopropylchlorocarbene, and 1-adamantylchlorocarbene. The σ → p transitions of these carbenes were used to directly monitor their reaction kinetics. The unusual and highly reactive N2CO compound, diazirinone, was obtained from the reaction of fluoride ion with p-nitrophenoxychlorodiazirine. Diazirinone fragmented to CO and N2 in a reaction that was exothermic by >90 kcal/mol. Dichlorodiazirine (DCD) was generated by the reaction of chloride ion with p-nitrophenoxychlorodiazirine. Reactions of dichlorocarbene generated from DCD are discussed.
Keywords: diazirines; carbenes; diazirinone; dichlorodiazirine.
*Paper based on a presentation at the 18th IUPAC International Conference on Physical Organic Chemistry (ICPOC-18), 20-25 August 2006, Warsaw, Poland. Other presentations are published in this issue, pp. 955-1151.