18088-19-2Relevant academic research and scientific papers
HETEROCYCLES RELATED TO 2,4-DIBORA 1,3-DIAZAROBENZENE
Allaoud, Smail,Frange, Bernard
, p. 129 - 136 (2007/10/02)
The reaction of ortho-substituted arylamines oY-C6H4NH2 (Y=H, Cl, Br, Me) with BX3, (X=F, Cl, Br, I) was investigated.By suitable choice of Y and X, this reaction may be directed to obtain, in a quantitative way, a new kind of heterocycle I instead of the expected trimeric species (oYC6H4NBX)3.The formation of I was found to be related to the bulk of Y substituent and to the nature of X, increasing in the order BCl3 a tertiary amine added, always gives the corresponding borazines.Some derivatives of I were prepared (X=Me, Y=Br, Me) and characterized by NMR (1H, 13C and 11B) and mass spectra. In connection with this study, we were led to the question of atropisomerism in the N-triarylborazines (oYC6H4NBX)3 when the starting arylamine bears an ortho substituent Y.As far as the compound Y=Me, X=Me is concerned, a sole isomer, the C3t one, could be obtained instead of the two expected.
