Routes to the formation of 1,3,5-triaryl- and 2,4,6-trichloro-1,3,5-triarylborazines and intermediate compounds

Abstract

The effect of ortho-substitution has been investigated in routes to the formation of 1,3,5-triaryl- and 2,4,6-trichloro-1,3,5-triaryl-borazines. The presence of two substituents in the ortho-positions inhibits the formation of the equivalent borazine, both in reactions involving the heating of a mixture of arylamine and triethylamine–borane and in those which involve heating the 1 : 1 adduct of the arylamine and trichloroborane. Products isolated in these cases include diazaboranes (bisaminoboranes)[(ArNH)₂BH], aminodichloroboranes [ArNHBCl₂], and triazaboranes (boronamines)[ArNH·BX·NAr·BX·NArH](X = Cl or H). A possible reaction path to the formation of borazines involving these intermediates is discussed.