| Popis: |
A 1/1 mixture of the tertiary amine boron trichloride adduct BDMA·BCl3 (BDMA = N,N-dimethylbenzylamine) and the amine hydrochloride RNH2·HCl (R = Me, Et) was heated in refluxing chlorobenzene to give the B- trichloro N-trialkylborazines (ClBNR)3 (R = Me, Et) with very good yield. With NH4Cl, the same reaction failed to give the related trimeric species (ClBNH)3, the latter compound being obtained in small amounts when the adduct ODMA·BCl3 (ODMA = N,N-dimethyloctylamine) is used instead of BDMA·BCl3 When applied to C6H5NH2·HCl, the same reaction leads to the expected borazine (ClBNC6H5)3 with moderate yield (23%), the main compound (77% according to 1H NMR) being a boron-nitrogen heterocycle derived from 1,3-diaza-2,4- diboranaphthalene (C6H5NBCl)2. Attempted isolation of the latter compound by chromatographic methods was unsuccessful. All these derivatives were characterized by high resolution 11B, 1H and 13C NMR. |
