131441-58-2Relevant academic research and scientific papers
SYNTHESIS AND CHARACTERIZATION OF THE FIRST BORANE ADDUCTS AND BORON CATIONS OF SOME N-ALKYL AND N-AMINOTRIPHENYLPHOSPHORANIMINES
Holley, William K.,Ryschkewitsch, George E.
, p. 271 - 284 (2007/10/02)
The first borane adducts of N-alkyl and N-aminotriphenylphosphoranimines, Ph3P=N-R, were prepared by two different general synthetic methods.The first method involved displacement of THF (tetrahydrofuran) from THF-borane by the free imines, and the second employed the reaction of LiBH4 with iminium bromides, Ph3P=N(R)*HBr, in diethyl ether.Imine boranes, Ph3P=N(R)*BH3, were synthesized where R = methyl, ethyl, n-propyl, isopropyl, t-butyl, dimethylamino, phenylamino, and methyl, phenylamino as the nitrogen attached groups.Symmetrical boron cations, (Ph3P=NR)2*BH2+, where R = methyl, ethyl, and n-propyl, were synthesized by displacement of iodide from in-situ generated iodoborane adducts, Ph3P=N(R)*BH2I, by the free imines.An attempt to form an unsymmetrical boron cation from (CH3)3N*BH2I and Ph3P=N(n-C3H7) resulted only in a mixture of the corresponding symmetrical boron cations.Physical, chemical and spectral properties of the borane adducts and boron cations, namely thermal and hydrolytic stabilities, infrared and NMR data are presented.Oxidative and reductive stabilities of the boron cations were studied.The borane adducts can be chlorinated with either HCl or Ph3CCl.Relative base strengths of some imines were determined by following the exchange of BH3 between borane adducts of (CH3)3N or 4-(CH3)C5H4N and the imines via NMR.
