Azomethine derivatives. Part VI. The action of diphenylketimine on diborane, trisdimethylaminoborane, trimethylborate, boron trifluoride and boron trichloride

Abstract

Diphenylketimine and diborane form and adduct Ph₂C:NH,BH₃ which at 120° loses hydrogen and rearranges to the borazine (Ph₂CHNBH)₃, for which the i.r., ¹H n.m.r. and mass spectroscopic results are given. Diphenylketimine reacts with trisdimethylamino-borane to replace dimethylamino- by diphenylketimino-groups, but even with an excess of the imine, incompleteness of reaction and difficulties of separating the products make the reaction unsuitable for the preparation of trisdiphenylketiminoborane. Boron trichloride and an excess of diphenylketimine likewise give impure trisdiphenylketiminoborane. Boron trifluoride and diphenylketimine give the adduct Ph₂C:NH, BF₃ which is sufficiently stable to withstand vacuum sublimation at 100–120°. Trimethylborate does not react with diphenylketimine at 70°.