4,5-dihydro- -bromide

This forms a dihydro bromide (brown plates) from which the free base is liberated by ammonia. The base crystallizes from nitrobenzene in brown crystals which decompose at 215°C. The picrate of 2,2 -diamino-4,4 -biselenazoie decomposes at 254°C. 

Brom-2,3-dihydro- -bromid E14a/2, 651 (2-Ethenyloxy-pyridin + Br2)... 

Brom-6,7-dihydro- -bromid 576 1 H-< Pyrazoliofl, 2-a]py razolium )-3-olat Pyrazolo[5,1-b]-1,3-oxazol... 

Dibromoisopentane (Isoprtne dihydro-bromide, 2 4Mibromo-2-methyliyutane)... 

Pteridinium bromide, 2-amino-4-ethoxy-3,4-dihydro-X-ray analysis, 3, 267 Pteridin-2-one, 4-amino-, 3, 273 hydrolysis, 3, 294 methylation, 3, 297 structure, 3, 273... 

Oxime 26 was prepared from 5,ll-dihydro-dibenzo[a,d]cyclohepten-10-one. The Hoch-Campbell reaction of 26 with 3-dimethylaminopropylmagnesium bromide produced aziridine 27 in 46% yield after acidic workup. Extension of the Hoch-Campbell reaction to steroids has also been reported. Thus, treatment of 3(3-hydroxy-5-pregnen-20-one oxime (28) with methylmagnesium iodide furnished a mixture of diastereomers, 20ot/20P,21-imino-20-methyl-5-pregnen-3P-ol (29) in a 50% combined yield and a 3 1 ratio. On the other hand, homo-adamantan-4-one oxime (30) was transformed to homo-adamantano[4,5-b]-2 -ethylaziridine (31) in 76% yield upon the action of... 

The nitration of l,2,5-selenadiazolo[3,4-/] quinoline 77 with benzoyl nitrate affords the 8-nitro derivative 78, whereas methylation with methyl iodide or methyl sulfate afforded the corresponding 6-pyridinium methiodide 79 or methosulfate 80, respectively (Scheme 29). The pyridinium salt 80 was submitted to oxidation with potassium hexacyanoferrate and provided 7-oxo-6,7-dihydro derivative 81 or, by reaction of pyridinium salt 79 with phenylmagnesium bromide, the 7-phenyl-6,7-dihydro derivative 82. Nucleophilic substitution of the methiodide 79 with potassium cyanide resulted in the formation of 9-cyano-6,9-dihydroderivative 83, which can be oxidized by iodine to 9-cyano-l,2,5-selenadiazolo [3,4-/]quinoline methiodide 84. All the reactions proceeded in moderate yields (81IJC648). 

Interestingly, a reverse isomerization (1,4-dihydro 1,2-dihydro) was observed when a 1,4-dihydroquinoline derivative was obtained by the reaction of lithiated l-ethoxycarbonyl-l,2-dihydroquinoline-2-phosphonate 36 with benzyl bromide... 

One gram of 6,7-dihydro-5H-dibenz[c,e] azepine hydrochloride was dissolved in water, made alkaline with concentrated ammonia, and the resultant base extracted twice with benzene. The benzene layers were combined, dried with anhydrous potassium carbonate, and mixed with 0.261 g of allyl bromide at 25°-30°C. The reaction solution became turbid within a few minutes and showed a considerable crystalline deposit after standing 3 A days. The mixture was warmed VA hours on the steam bath in a loosely-stoppered flask, then cooled and filtered. The filtrate was washed twice with water and the benzene layer evaporated at diminished pressure. The liquid residue was dissolved in alcohol, shaken with charcoal and filtered. Addition to the filtrate of 0.3 gram of 85% phosphoric acid in alcohol gave a clear solution which, when seeded and rubbed, yielded 6-allyl-6,7-dihydro-5H-dlbenz[c,e] azepine phosphate, MP about 211°-215°C with decomposition. 

Preparation of 4-aza-S-(N-methyl-4-piperidyll-10,11-dihydro-SH-dibenzo[a,d]cycloheptene-S-ol Add 17.4 g of N-methyl-4-chloropiperidine to a stirred mixture containing 3.2 g of magnesium, 20 ml of anhydrous tetrahydrofuran, 1 ml of ethyl bromide and a crystal of iodine. Reflux for two hours, cool to 30°-35°C and add a solution of 13 g of 4-aza-10,11 -dihydro-5H-dibenzo[a,d] cycloheptene-5-one in 25 ml of tetrahydrofuran. Stir for five hours, remove the solvent by distillation in vacuo and add 250 ml of ether. Add 100 ml of 10% ammonium chloride solution and extract the mixture with chloroform. Concentrate the chloroform solution to a residue and recrystallize from isopropyl ether obtaining 20 g of the carbinol,... 

D) Preparation of 4-[1 -Methyl-Piperidyl-(4 )]-9,10-Dihydro-4H-Benzol4,5]Cyciohepta[1,2-b] Thiophen-(4)-ol 0.94 g of magnesium filings which have been activated with iodine are covered with a layer of absolute tetrahydrofuran and etched with a few drops of ethylene bromide. A solution of 5.0 g of 1-methyl-4-chloropiperidine in 5 ml of tetrahydrofuran is then added dropwise and boiling then effected for a further hour under reflux. After cooling to room temperature, the solution of 4.5 g of 9,lO-dihydro-4H-benzo[4,5] cyclohepta[1,2-b] thio-phen-(4)-one in 5 ml of tetrahydrofuran is added dropwise. 

The dehydrohalogenation reaction has been extended to benzannulated oxepins. Elimination of hydrogen bromide from 3-bromo-4-phenyl-2,3-dihydro-l-benzoxepin with 1,5-diazabicyclo-[4.3.0]non-5-ene gives 4-phenyl-1-benzoxepins 15a15 and 15b16 in low yield. 

Halo-l-benzothiepins 4 can be synthesized by the treatment of 7a-halobenzo[fe]cyclopropa-[e]thiopyran-7-ols 2 with hydrogen bromide and subsequent hydrogen bromide elimination from the 2,4-dihalo-2,3-dihydro-l-benzothiepins 3 by l,5-diazabicyclo[4.3.0]non-5-ene (DBN).9 The alcohols 2 are prepared by Grignard reaction of the corresponding 7a-halobenzo[ft]cyclopropa[c]thiopyran-7-ones l18 and are used for the synthesis without purification. The intermediate dihalodihydro-l-benzothiepins 3 are not isolated due to their thermal lability related and more stable compounds are described in Section 2.1.2.1. 

---