Benzo 2-chloro

The use of free-radical reactions for this mode of ring formation has received rather more attention. The preparation of benzo[Z)]thiophenes by pyrolysis of styryl sulfoxides or styryl sulfides undoubtedly proceeds via formation of styrylthiyl radicals and their subsequent intramolecular substitution (Scheme 18a) (75CC704). An analogous example involving an amino radical is provided by the conversion of iV-chloro-iV-methylphenylethylamine to iV-methylindoline on treatment with iron(II) sulfate in concentrated sulfuric acid (Scheme 18b)(66TL2531). 

H NMR, 4, 561 <65MI31002> Benzo[b]furan-2-carboxylic acid, methyl ester UV, 4, 589 Benzo[b]furan-3-carboxylic acid, 6-chloro-4,5,7-trifluoro-2-methyl-, ethyl ester C NMR, 4, 568 <72JCS(P2)1733> Benzo[b]furan-3-carboxylic acid, 6-cyano-4,5,7-trifluoro-2-methyl-, ethyl ester C NMR, 4, 568 <72JCS(P2)1733>, 569 <72JCS(P2)1733>... 

Benzo[h]selenophene, 3-bromo-2-lithio-synthesis, 4, 956 Benzo[h]selenophene, 3-chloro-synthesis, 4, 116... 

Benzo[h]tellurienylethyl acetate solvolysis, 4, 952 Benzo[h]tellurophene, 3-bromo-synthesis, 4, 954 Benzo[h]tellurophene, 3-chloro-synthesis, 4, 954... 

Benzo[i]thiophene, 6-/-butyl-3-methyl-synthesis, 4, 880 Benzo[6]thiophene, 2-chloro-... 

Benzo[6]thiophene, 7-chloro-3-methyl-electrophilic substitution, 4, 798... 

Benzo[b]thiophene, 3-chloro-2-phenyl-synthesis, 4, 116 Benzo[6]thiophene, 2-cyano-synthesis, 4, 921 Benzo[6]thiophene, 3-cyano-synthesis, 4, 922... 

Benzo[b]thiophene-2-carbonyl chloride, 3-chloro-5,6-dimethoxy-synthesis, 4, 933... 

Benzo[b]thiophene-2,3-quinone, 5-chloro-oxidation, 4, 824 Benzothiophenes, 4, 863-934 biological activity, 4, 911-913 intramolecular acylation, 4, 761 mass spectrometry, 4, 739 metabolism, 1, 242 phosphorescence, 4, 16 reactivity, 4, 741-861 spectroscopy, 4, 713-740 structure, 4, 713-740 substituents reactivity, 4, 796-839... 

Acetoxy-l[Pg.302]

S >Olmethaxytrltyl>2 -d oxythylmldlne-3 -phosphate (3). A sohjllon ot 1 mmol ot 1 (T thymine, DMT-4,4 -dimethoxyti1tyl) in dioxane (8 mL), pyridine (1 mL) and a slight excess ot 2-chloro-5,6-benzo-1,3-dioxaphosphorfn-2-one 2 (1 mi. ot a 1.2S M solution in dioxane) was stirred at 20 C After 5 mki TLC Indicated complete conversion oM Into 3 with zero mobility. Water was added and after work up 3 was isolated in 88% yield. 

The usual order found with halogenonitrobenzenes is F > Cl Br I, the order of Cl and Br being variable, just as in heteroaromatic reactivity. The position of fluorine is of interest the available data indicate that it is usually the same as for nitrobenzene derivatives. Thus, in acid hydrolysis the order F > Cl for 2-halogeno-quinolines can be deduced beyond doubt since the fluoro derivative appears to react in the non-protonated form and the chloro derivative to resist hydrolytic attack even in the protonated form under appropriate conditions (Section II,D, l,d). Furthermore, in the benzo-thiazole ring, fluorine is displaced by the CHgO reagent at a rate 10 times that for chlorine. ... 

The monoazanaphthalenes provide a good illustration of the effect of henzo-fusion onto an azine and of the variation of the effect with the position of fusion. A benzo ring can be fused onto 2-chloro-pyridine at the 3,4- [leading to 1-chloroisoquinoline (393)], at the 4,6- [forming 3-chloroisoquinoline (394)], or at the 5,6-position [yielding 2-chloroquinoline (395)]. The first and the last fusions... 

Even though data for a quantitative comparison are lacking, the effect of the position of benzo-fusion onto pyridazines is analogous to that with pyridines in producing the very poorly reactive 3-chloro-cinnoline (396) and highly reactive 1-chlorophthalazine (Table XV, lines 8 and 9). 

Condensation of the dianion of 1,2-dimercaptobenzene (380) with 1-chloro-8-nitronaphthalene (483) in DMF provided 45% of benzo[2,3]naphthalene [5,6,7-/j][l,4]dithiepin (484) and a small amount of its 5-oxide 485 (Eq. 44) (89JHC667). Though the structure of 485 was adequately determined (NMR studies, X-ray crystallography), its formation was not definitely explained. 

B) Preparation of 7-Chloro-3-Methoxycarbony/-5-Phenyl-2-0xo-2,3-Dihydro-iH-Benzo [fl-1,4-Diazepine (4347 CB) A solution of 9.2 g (0.04 mol) of compound 4356 CB in 20 ml of methanol is added dropwise, in the course of one hour and 30 minutes, to a boiling solution of 9.2 g (0.05 mol) of the hydrochloride of methyl aminomalonate in 30 ml of methanol. When this is completed, heating under reflux is continued for 30 minutes and the product then concentrated to dryness under reduced pressure. The residue is taken up in water and ether, the ethereal layer separated, the product washed with water and dried over sodium sulfate. The solvent is evaporated under reduced pressure. The residue, which consists of the methyl ester, could not be obtained in the crystalline state. It is dissolved in 25 ml of acetic acid, heated under reflux for 15 minutes, the product evaporated to dryness and the residual oil taken up in ether. A colorless solid separates which... 

After cooling, the solid is filtered by suction and washed with alcohol at 96°C. The product is dried at ordinary temperature in a high vacuum. A colorless solid is obtained (quantitative yield), which is completely soluble in water. The aqueous solution is strongly alkaline in reaction when acidified with acetic acid and heated on a water bath, it yields a precipitate of 7-chloro-5-phenyl-2-oxo-2,3-dihydro-1 H-benzo[fl-1,4-diazepine. 

To a mixture of 3.0 grams of N,N -diacetyl-o-anilamide and 20 ml of acetic acid Is added a previously prepared solution of 1.5 grams of chlorine in 31 cc of acetic acid. The reaction mixture is allowed to stand at room temperature for 3 hours and is then evaporated to dryness on a steam bath under reduced pressure. The resulting solid residue is recrystallized from ethanol, yielding the intermediate N,N -diacetyl-2-sulfamyl-4-chloroaniline. The intermediate compound is fused in an oil bath at 250-260°C for 15 minutes, cooled and the product so obtained is crystallized from 80% ethanol yielding 3-methyl-7-chloro-1,2,4-benzo-thiadiazine-1,1-dioxide, MP 330°C. 

Chemical Name 3 -Chloro-Q -[methyl[(morpholinocarbonyl)methyl] amino] -o-benzo-toluldide... 

B) Preparation of 7-Chloro-1,2,3,4-Tetrahydro-1-Methyl-6H-1,4-Bemodiazepin-5-one A mixture of 25.25 g (0.1 mol) of 4-acetyl-7-chloro-1,2,3,4-tetrahydro-1-methyl-5H-1,4-benzo-diazepin-5-one, 33.3 ml (0.1 mol) of 3 N sodium hydroxide and 350 ml of ethanol was heated under reflux for 15 minutes and then concentrated to dryness in vacuo. The residue was treated with 500 ml of water, collected and washed with ethanol to give 20.2 g... 

B) Add to a suspension of 34 g of 3-acetoxy-7-chloro-1,3-dihydro-5-phenyl-2H-1,4-benzo-diazepin-2-one in 80 ml of alcohol, 6 ml of 4N sodium hydroxide. Allow to stand after complete solution takes place to precipitate a solid. Redissolve the solid by the addition of 80 ml of water. Acidify the solution with acetic acid to give white crystals. Recrystallize from ethanol to obtain 7-chloro-1,3-dihydro-3-hydroxy-5-phenyl-2H-1 4-benzodiazepin-2-one, melting point 203°Cto 204°C. 

D/chloro-5-Cyclohexyl-2-Oxo-2,3-D/hydro 1 H-Benzo(fj-Diazepine-1,4 fa) Process Using Sodium Hypochlorite — 40 ml of a solution of sodium hypochlorite of 14.5 British chloro-metric degrees are added to a suspension of 5.4 grams of 7 chloro-5 cyclohexyl-2 oxo-2,3-dihydro 1 H-benzo(f)diazepine-1,4 in BO ml of methylene chloride. The mixture is stirred at room temperature for 15 minutes the solid dissolves rapidly. The organic iayer is decanted, washed with water, dried over anhydrous Sodium sulfate and the solvent evaporated under reduced pressure without exceeding a temperature of 30 C. The residue is taken up in a little diisopropyl ether and the crystals which form are dried. They are recrystallized as rapidly as possible from ethyl acetate. Colorless crystals are obtained (3.9 grams yield, B5%) MP < = 163°C, with decomposition. 

Chemical Name 8-Chloro-1-methyl-6-(o-chlorophenyl)4H-s-triazolo[4,3-al [1,4] -benzo-diaz epine... 

Chloro-5[Pg.1622]

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