4H-1,2-Diazepines

The Diels-Alder reaction of cyclopropenes with 1,2,4,5-tetrazines (see Vol.E9c, p 904), a reaction with inverse electron demand, gives isolable 3,4-diazanorcaradienes 1, which are converted into 4H-1,2-diazepines 2 on heating. The transformation involves a symmetry allowed [1,5] sigmatropic shift of one of the bonds of the three-membered ring, a so-called walk rearrangement , followed by valence isomerization.106,107... 

Triphenyl-4H-1.2-diazepin 101 liegt ausschlieBlich in der mono-cyclischen Form mit zwei C=N-Bindungen vor, da hier das entsprechende... 

Reactions of hydrazine and methylhydrazine with pyrylium or thiinium salts, e.g., 182, provide major routes to 4H-1,2-diazepines 183 and 1/7-1,2-diazepines 184 <1980CJC494>. Selenopyrylium salts react with anhydrous hydrazine in dry acetonitrile in a similar fashion (Scheme 90) <2005CPB60, CHEC-III(13.04.10)154>. 

H-1,2- Diazepines acylation, 7, 602 nucleophilic reactions, 7, 603 protonation, 7, 601 from pyrylium salts, 3, 660 4-subs tituted synthesis, 7, 604 synthesis, 7, 598, 599 thermal reactions, 7, 600... 

C29H21N5O7, 3,5,7-Triphenyl 4H-1,2-diazepine picrate, 38B, 623 CaoHiftOg, Perylene-pyromellitic dianhydride complex, 30B, 254 C30H1gClftOg, 2,3-Dichloro-1,4-naphthoquinone - a-naphthol (2 1),... 

Dihydro-4H-l,2-diazepin-4-ones from 3-diazoacety 1-/4 -pyrazolines... 

Chemical Name 8-Bromo-6-(o-chlorophenyl)-1-methyl-4H-s-triazolo-[3,4c] -thieno-[2,3e] -1,4-diazepine... 

An iron tricarbonyl complex 19-21 (0.338 g, 1 mmol) and freshly sublimed Me3NO (0.6 g, 8 mmol) in acetone was left at rt for 4h. Evaporation, followed by flash chromatography (alumina, Et20), gave the corresponding unstable l-troponyl-l//-l,2-diazepines 22-24 in 76, 76 and 44% yield, respectively. 

Preparation of (6-(2-chlorophenyl)-9-[(4-methoxyphenyl)thiocarbamoyl]-1-methyl-7,8,9,10-tetrahydro-4H-pyrido[4, 3 4,5]tliieno[3,2-f]-1,2,4-triazolo[4,3-a]-l,4-diazepine... 

Cyclobnta b qninoxaline 3,8-Dimethyl-l,2-dithiono-l,2,3,8-tetrahydro- E17f, 988 (Oxo,Oxo - Thiono.Thiono) 6H-1,3-Thiazin 5-Cyan-4-methyl-thio-2-phenyl- E5, 1362 (CO-NH2 - CN) 4H-(Thieno 2,3-c -l,2-diazepin) ... 

A range of multicomponent processes have been reported including an acid-free Ugi reaction for the synthesis of 5H-benzo[e][l,4]diazepines (14SL1680), an interesting post-Ugi copper-catalyzed intramolecular UUmaim coupling approach for the synthesis of 4H-benzo[/]imidazo[l,4]diazepin-6-ones (14TL2070) and a reaction between aromatic 1,2-diamines, Meldrum s acid, an isocyanide, and an arylidene malononitrile for the preparation of l,2,4,5-tetrahydro-2,4-dioxobenzo[l)][l,4]diazepines (14T9512). 

Cl3H12CIN3O2S, 7-Chloro-l,3,5-trimethyl-5H-pyrimido[5,4-b] 1,4)ben-zothiazine-2,4(1H,3H)-dione, 38B, 398 Cl3H12N2O2S, 5,6-Dihydro-6-(2-oxo-propyl)-4H-pyrrolo[1,2-a]thieno-[3,2-f][1,4-diazepine]-4-one, 45B, 380 Cl3H14N2O2S, 2-Amino-4,5-dihydro-7,8-dimethoxynaphtho[1,2-d]thia-zole, 43B, 483... 

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