Dibenz b,/ azepine

A detailed study of the dehydrogenation of 10.1 l-dihydro-5//-benz[6,/]azcpinc (47) over metal oxides at 550 C revealed that cobalt(II) oxide, iron(III) oxide and manganese(III) oxide are effective catalysts (yields 30-40%), but formation of 5//-dibenz[7),/]azepinc (48) is accompanied by ring contraction of the dihydro compound to 9-methylacridine and acridine in 3-20 % yield.111 In contrast, tin(IV) oxide, zinc(II) oxide. chromium(III) oxide, cerium(IV) oxide and magnesium oxide arc less-effective catalysts (7-14% yield) but provide pure 5H-dibenz[b,/]azepine. On the basis of these results, optimum conditions (83 88% selectivity 94-98 % yield) for the formation of the dibenzazepine are proposed which employ a K2CO,/ Mn203/Sn02/Mg0 catalyst (1 7 3 10) at 550 C. 

A mild, but more restricted, A -alkylation procedure (Method C) for 5//-dibenz[b,/]azepines involves the action of alkyl halides on their Af-thallium derivatives.190... 

Attempts to prepare 5-vinyl-5F7-dibenz[b,/]azepine by alkylation of 5i/-dibenz[b,/]azepine with 2-chloroethyl-p-toluenesulfonate followed by dehydrochlorination, or by direct vinylation with acetylene under pressure in toluene or in dimethyl sulfoxide, have failed.194 Also, 5H-dibenz[b,/]azepine fails to react with acryloyl chloride, although the 5-acryloyl derivative 8 (R = COCH = CH2 mp 122 — 123 C) has been prepared in 65% yield by condensing dibenz-azepine 5 with 3-chloroacryloyl chloride, followed by dehydrochlorination of the product with l,8-diazabicyclo[5.4.0]undec-7-ene in dimethyl sulfoxide at 80-90°C.194... 

A-Acylations of 57/-dibenz[b,/]azepine (5) can be carried out under standard conditions,69 124 142,196 197 as exemplified below. There is some evidence to suggest that acetylation under acidic conditions is accompanied by ring contraction to yield acridones.32... 

Dibenz[b,/]azepine (5) with triethoxymethylenium tetrafluoroborate (Method E), unlike the 10,11-dihydro derivative which undergoes C- and Ar-formylation, produces only a low yield of 5//-dibenz[6,/]azepine-5-carbaldehyde (8, R = CHO).198... 

Dibenz[b,/]azepinc-5-carbonitrile (14), an alternative intermediate for the synthesis of Car-bamazepine, is obtained (47%, as the hydrobromide) by stirring 5//-dibenz[b,/]azepine (5) with cyanogen bromide in chloroform solution at room temperature,203 or with cyanogen chloride in dimethylacetamide.204... 

Dibenz[b,/ azepine, 5-acetyl-10-cyano-reduction, 7, 517 Dibenz[6,/ azepine, 1-acyl UV spectra, 7, 501-502 Dibenz[6,/]azepine, N-acyl-10,11-dihydro-NMR, 7, 499... 

Of the four dibenzazepines, 577-dibenz[b,d]azepine (19), 577-dibenz [b,e]azcpinc (20), 577-dibenz[b,/]azepine (21), and 677-dibenz[c,e]azepine (22), only 21 is known as such (74CRV101 84JHC197), while 22 exists as the nonaromatic 577-tautomer (81LA240). 

DIHYDRO-5-(3-(DIMETHYLAMINO)PROPYL)-5H-DIBENZ(b, )AZEPINE HYDROCHLORIDE see DLH630... 

H-Dibenz[b,/]azepine, 10,11 -dihydro-5-methyl-,3C NMR, 7, 498 <74JCS(P2)1648> 5FF-Dibenz[c,e]azepine HNMR, 7, 497 (81LA240) 6H-Dibenz[c,e]azepine, 6-allyl-5,7-dihydro-13C NMR, 7, 498 (79JPS890) 5H-Dibenz[b,/]azepine-5-carboxylic acid, 10,11-dihydro-, ethyl ester l3C NMR, 7, 498 <74JCS(P2)1648>... 

It has been previously shown that the reactive intermediate 5-acetyl-10,11-didehydro-5//-dibenz[b azepine prepared by base treatment of 5-acetyl-10-bromo-5//-dibenz[bJ]azepine will also undergo reaction with furan and cyclohexadiene <7ijmci839>, <91joc3906>. This work has now been extended by the... 

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