Mono 1,4-diaza-2,3-diborinane and bicyclic species: Synthesis and structures

The derivatives of diazadiborinane containing a ring with two nitrogen atoms and two boron atoms are a class of 6-membered heterocyclic compounds. Previous studies conducted on the synthesis of diazadiborinane showed that their structures are highly unstable and that some prepared isomer Mixtures have no defined mono structure. New monocyclic 1,4-diaza-2,3-diborinane derivatives B-2{1,4-(NAr)(2)C2H4} 3ah-fh and the new bicyclic (B-2{1,2-(NAr)(2)C2H4)(2)) isomer 6 were prepared. The structures of these new derivatives were characterized using nuclear magnetic resonance (NMR) spectroscopy. The molecular and crystal structures of 3ah, 3bh, 3ch, 3fa and bicyclic species 6c were determined using the single crystal X-ray diffraction technique. (C) 2016 Elsevier Ltd. All rights reserved.