42168-28-5

Upstream product

• 917-64-6 methyl magnesium iodide 
• 95-53-4 o-toluidine 
• 10294-33-4 boron tribromide 
• 13517-10-7 boron triiodide 

Relevant academic research and scientific papers

Synthese d'heterocycles bore-azote-carbone. Structure cristallographique du dimethyl-2,4 o-tolyl-3 methyl-8 dibora-2,4 diazaro-1,3 naphtalene

The reaction of anilines o-YC6H4NH2 (Y = H, F, Cl, Br, Me) with boron trihalides BX3 (X = F, Cl, Br, I) has been investigated.With BF3, only borazine derivatives (o-YC6H4NBX)3 (X = F) could be obtained, whereas BI3 mainly gives heterocycles related to diboradiazaronaphthalene (o-YC6H4NBX)2 (X = I).The steric bulk of Y has been shown to play an important role in obtaining these boron-nitrogen-carbon heterocycles.After methylation (X = Me), all these derivatives have been characterised by NMR spectroscopy.The crystal structure of 2,4-dimethyl-3-o-tolyl-8-methyl-2,4-dibora-1,3-diazaronaphthalene has been determined.A slight puckering of the diboradiazaronaphthalene part of the molecule is observed, which results in a boat conformation for the mineral part of this heterocycle and a reduced conjugation with the adjacent benzene ring.

HETEROCYCLES RELATED TO 2,4-DIBORA 1,3-DIAZAROBENZENE

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.

Atropisomerism in aryl-substituted borazines

The N,N′,N″-tri-o-tolylborazines (o-CH3C6H4NBX)3 (X = Cl, Br, Me, Et) were prepared and studied by means of 1H and 13C NMR. The methyl derivative (X = Me) resulting from the reaction of CH3MgI on the B,B′,B″-trichloro-N,N′,N″-tri-o-tolyl-borazine (X = Cl) in diethyl ether was shown to be a mixture of the cis isomer alone with B-hydroxy byproducts that were identified. This methylation reaction fails to provide the expected trans isomer for steric reasons: instead, B-hydroxy compounds appear during the hydrolysis step.