N-BH3 ADDUCTS OF TRIALKYL-1,3,5-TRIAZACYCLOHEXANES WITH STABLE STEREOGENIC NITROGEN ATOMS, STEREOCHEMICAL STUDY

Article abstract of DOI:10.1016/0957-4166(95)00202-Z

The syntheses and stereochemical studies of N-BH3 adducts of trialkyl-1,3,5-triazacyclohexanes <1, R=CH3; 2, R=iso-C3H7; 3, R=CH(CH3)C6H5) (R); 4, R=tert-C4H9> are reported.Different reagent ratios were used in order to obtain mono- and di-N-borane adducts.Tri-N-borane adducts were never observed; di-N-borane adducts were formed with triazine 1 and 2 whereas 3 and 4 afforded only the mono-boranes.It appears that low steric strain is an important factor in the syntesis of these compounds.Borane addition produced in all cases ring and nitrogen conformationally stable compounds which were studied by NMR All the reactions were 100percent stereoselective affording one isomer in each reaction.