title: Synthesis and characterization of silyldichloramines, their reactions with F- ions, instability of N2Cl2 and NCl2-, and formation of NCl3.
abstract: Only two silyldichloramines, (C6H5)3SiNCl2 and (CH3)3SiNCl2, have been reported in the literature. The synthesis of the former was successfully repeated, and its structure was established by single-crystal X-ray diffraction and vibrational spectroscopy. Attempts to prepare (CH3)3SiNCl2 were unsuccessful; however, a new trialkylsilyldichloramine, t-BuMe2Si-NCl2, was prepared and characterized by Raman and multinuclear NMR spectroscopy. The reaction of t-BuMe2SiNCl2 with (CH3)4NF in CHF3 solution at -78 degrees C, followed by removal of all volatile products at -30 degrees C, produced the expected t-BuMe2SiF byproduct and a white solid consisting of NCl3 absorbed on Me4NCl. The NCl3 could be reversibly desorbed from the substrate and was identified as a neat liquid at room temperature by Raman spectroscopy. The observed final reaction products are consistent with the formation of an unstable N(CH3)4+NCl2- intermediate which decomposes to N(CH3)4+Cl- and NCl molecules which can dimerize to N2Cl2. Theoretical calculations confirm that NCl2- can readily lose Cl- and that N2Cl2 also possesses a low barrier toward loss of N2 to give chlorine atoms and, thus, can account for the formation of NCl3.
authors.affiliation: Loker Hydrocarbon Research Institute and Department of Chemistry, University of Southern California, Los Angeles, California 90089, USA. stefan.schneider@edwards.af.mil
authors.forename: Stefan
authors.initials: S
authors.lastname: Schneider
authors.forename: Michael
authors.initials: M
authors.lastname: Gerken
authors.forename: Ralf
authors.initials: R
authors.lastname: Haiges
authors.forename: Thorsten
authors.initials: T
authors.lastname: Schroer
authors.forename: Jerry A
authors.initials: JA
authors.lastname: Boatz
authors.forename: David A
authors.initials: DA
authors.lastname: Dixon
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Grant
authors.forename: Karl O
authors.initials: KO
authors.lastname: Christe