title: Synthesis and characterization of secondary nitrosamines from secondary amines using sodium nitrite and p-toluenesulfonic acid.
abstract: We synthesized nitrosamines (R2N-NO) with R = iPr (1), nPr (2), nBu (3), and hydroxyethyl (4) from the amine using sodium nitrite/p-toluenesulfonic acid in CH2Cl2. The rate of formation of 1-4 increases in the direction iPr<nPr<nBu<CH2CH2OH. Compounds 1-3 were obtained as colorless solids, whereas 4 is a bright yellow liquid. Compounds 1-4 were characterized by elemental analysis, MS, IR, and multinuclear NMR ((1)H, (13)C, and (15)N) spectroscopies. Additionally, we measured the UV/Vis spectra of all compounds, which show maxima of absorption at approximately 221 nm and molar extinction coefficients between 3043 and 4859 L mol(-1)  cm(-1). We calculated the optimized structures of 1-4 (B3LYP/6-311+G(d,p)) and computed the NMR spectroscopic chemical shifts and infrared frequencies. Furthermore, we carried out a natural bond orbital (NBO) analysis of the nitrosamine moiety. Lastly, the compounds described in this work are valuable starting materials for the synthesis of 2-tetrazenes with potential interest to replace highly toxic hydrazines in rocket propulsion.
authors.affiliation: Laboratoire Hydrazines et Composés Ènergétiques Polyazotés, UMR 5278/CNRS/UCBL/CNES/SME-SAFRAN, Université Claude Bernard Lyon 1, 3è étage, 22, av. Gaston Berger, 69622 Villeurbanne (France), Fax: (+33) 472-431-291. carlos.miro-sabate@univ-lyon1.fr.
authors.forename: Carles
authors.initials: C
authors.lastname: Miró Sabaté
authors.forename: Henri
authors.initials: H
authors.lastname: Delalu
keywords: amines; energetic materials; hydrazines; sodium; synthetic methods