摘要 |
<p>The invention refers to a new process for the preparation of a valuable intermediate, 5H-Dibenzo-(b, f)-azepine or iminostilbene by catalytic dehydrogenation of lO,ll-Dihydro-5H-dibenzo-(b, f)-azepine or iminodibenzyl in liquid phase in one step in the presence of hydrogen acceptor. Dimethylaniline or diphenylether may be used as a solvent and as catalyst, nobel metal catalysts, such as platinum or palladium on activated carbon or metaloxide catalysts, such as Fe2O3 may be used in the dehydrogenation reaction. Nitrotoluenes, dimethylmaleate or tetrachlorobenzochinone may be used as hydrogen acceptors. The yield of iminostilbene is 77-82 DEG C of the theoretical.</p> |