M-Bromosuccinimide

Bromocriptine Bromocriptine, 2-bromoergocriptine (10.1.13), is a semisynthetic derivative of a natural ergot alkaloid, ergocriptin (a derivative of lysergic acid), which is synthesized by bromination of ergocriptin using M-bromosuccinimide [18,19]. 

Radical substitution reactions, such as the light-induced chlorination of methane and the allylic bromination of alkenes with M-bromosuccinimide (Review Table 3, reaction 5), are also common. The key step in all these reactions is that a radical abstracts an atom from a neutral molecule, leaving a new radical. 

The benzylic position of alkylbenzenes can be brominated by reactioa with M-bromosuccinimide, and the entire side chain can be degraded to i carboxyl group by oxidation with aqueous KMnO. Althoi h siromatic ring are less reactive than isolated aJkene double bonds, they can be reduced to cyclohexanes by hydrogenation over a platinum or rhodium catalyst. In addition, aryl alkyl ketones are reduced to alkylbenzenes by hydrogenak

Oxy-diazines, with the oxygen a to nitrogen, can be converted into halo- and thio compounds " using the same reagents used for 2- and 4-pyridones, including M-bromosuccinimide with triphenylphosphine. " The reactions of 0-silylated pyrazinones with phosphorus(III) bromide or phosphorus(V) chloride are also efficient. ... 

When iVj-acyl-tryptophans are exposed to strong acid, the indolium cation is trapped by cyclisation involving the side-chain nitrogen. Comparable tricycles result from phenylselenylation of protected tryptophan or reaction with 4-methyl-l,2,4-triazoline-3,5-dione, ° or dimethyl(succinimido)sulfonium chloride (a CH2SMe group ends up at the indole C-3)." If M-bromosuccinimide is employed, the initially formed 3-bromo-tricycle loses hydrogen bromide to produce an aromatic indole. ... 

Monobromination of 233 proceeded on treatment with one equivalent of M-bromosuccinimide (NBS) in HOAC/HCO2H (3 1) [187] affording the natural product flustrabromine (234) in 53% isolated yield. As side product, the 4-brominated analogue was obtained (20%). Alkaline hydrolysis of flustrabromine (234) afforded deformylflustrabromine (235), which afforded rac-flustramine C (236) in one single step on treatment with NBS (1 equiv.). / ac-flustramine C (236) was reduced diastereoselectively to rac-dihydroflustramine C (237) with DIBAL-H [188]. 

Preparation of 2,3-disubstituted corannulene derivatives requires an alternative synthesis (Scheme 9) [57]. 2,3-DiphenyIcorannulene (32) was generated by the Ni-catalyzed Kumada coupling of 2,3-dichlorocorannulene (19) with phenyl-magnesium bromide. Similarly, the Ni-catalyzed methylation of 19 with trimethyl-aluminum yielded 2,3-dimethylcorannulene (33), from which the bis-(bromomethyl) derivative 34 was obtained by benzyUc bromination with M-bromosuccinimide. Moreover, heating 19 in diethylene glycol monomethyl... 

More recently, Santoyo Gonzalez and co-workers [43] reported the Hofmann rearrangement of amide 84 into cyclic carbamate 85 (40% yield. Scheme 24). This was achieved with a mixture of mercuric acetate, M-bromosuccinimide and M,JV-dimethylformamide. 

Bromomethylanthraquinone [7598-10-9] M 301.1, m 200-202°. Recrystd from AcOH, the crystals are washed with a little Et20, dried in air and then in vac at 100°. It is prepared by bromination of 2-methylanthraquinone with Br2/PhN02 at 145-150°, or 7V-bromosuccinimide in CCI4 containing a trace of (PhCOO)2. 

V-Bromosuccinimide [128-08-5] M 178.0, m 183-184°(dec). TV-Bromosuccinimide (30g) was dissolved rapidly in 3(X)mL of boiling water and filtered through a fluted filter paper into a flask immersed in an ice bath, and left for 2h. The crystals were filtered, washed thoroughly with ca l(X)mL of ice-cold water and drained on a Buchner funnel before drying under vac over P2O5 or CaCl2 [Dauben and McCoy J Am Chem Soc 81 4863 7959]. Has also been crystd from acetic acid or water (10 parts, washed in water and dried in vacuo, [Wilcox et al. J Am Chem Soc 108 7693 1986 Shell et al. J Am Chem Soc 108 121 7956 Phillips and Cohen J Am Chem Soc 108 2013 7956.]... 

Preparation of 9a-Bromo-110,17a 1 Trihydroxy-16 -Methyl-4-Pregnene-3,20-Dione 21-Acetate To a mixture of 620 mg of 17a,21-dihydroxy-16/3-methyl-4,9(11 )-pregnadiene-3,20-dione 21-acetate and 330 mg of N-bromosuccinimide in 10 ml of dioxane and 3.2 ml of water cooled to 10°C was added 1.8 ml of cold 1 M aqueous perchloric acid. The mixture was stirred at 15°C for 3 hours. Excess N-bromosuccinimide was destroyed by addition... 

Dissolve 71 g. of P-methylnaphthalene in 460 g. (283 ml.) of A.B. carbon tetrachloride and place the solution in a 1 -litre three-necked flask equipped with a mechanical stirrer and reflux condenser. Introduce 89 g. of JV-bromosuccinimide through the third neck, close the latter with a stopper, and reflux the mixture with stirring for 16 hours. Filter ofiT the succinimide and remove the solvent under reduced pressure on a water bath. Dissolve the residual brown oil (largely 2-bromomethyl naphthalene) in 300 ml. of A.R. chloroform, and add it to a rapidly stirred solution of 84 g. of hexamine in 150 ml. of A.R. chloroform contained in a 2-litre three-necked flask, fitted with a reflux condenser, mechanical stirrer and dropping funnel maintain the rate of addition so that the mixture refluxes vigorously. A white solid separates almost immediately. Heat the mixture to reflux for 30 minutes, cool and filter. Wash the crystalline hexaminium bromide with two 100 ml. portions of light petroleum, b.p. 40-60°, and dry the yield of solid, m.p. 175-176°, is 147 g. Reflux the hexaminium salt for 2 hours with 760 ml. of 60 per cent, acetic acid, add 160 ml. of concentrated hydrochloric acid, continue the refluxing for 5 minutes more, and cool. Extract the aldehyde from the solution with ether, evaporate the ether, and recrystallise the residue from hot -hexane. The yield of p-naphthaldehyde, m.p. 69-60°, is 60 g. 

Funatsu, M., A. M. Green, and B. Witkop Differential oxydation of protein-bound tryptophane and tyrosine by N-bromosuccinimide in urea solutions. J. Amer. chem. Soc. 86, 1846—1848 (1964). 

To a solution of 17.95 gm (0.0634 mole) of f-butyl-2-(p-bromophenyl) carbazate and 4.94 gm (0.0626 mole) of dry pyridine in 300 ml of methylene chloride is added, in small portions, over a 20 min period, 11.13 gm (0.0551 mole) of N-bromosuccinimide. The red solution is allowed to stand at room temperature for 3 hr. Then the reaction mixture is washed in turn with two portions of 100 ml of water, 125 ml of 10% aqueous sodium hydroxide, and another two portions of water. The product solution is then dried with anhydrous potassium carbonate. The solvent is removed by distillation under reduced pressure, using a water bath at 50°C as the source of heat. On standing, the red liquid crystallizes to a yellow-orange solid which is dissolved in methanol, treated with charcoal, filtered, and the filtrate treated with just sufficient water to cause product precipitation yield 15.34 gm (86%), yellow-orange crystals, m.p. 66°-67°C. 

To a stirred methylene chloride solution of 4.62 gm (15 mmoles) of 1-phenyl-2-(diphenylphosphine oxide)hydrazine maintained at —20°C is added over a 10 min period 2.67 gm (15 mmoles) of iV-bromosuccinimide. The solution is allowed to warm to room temperature, and stirring is continued for 10 min. The solids formed are removed by filtration and discarded. The solution is washed in turn with two portions of 5 % aqueous sodium thiosulfate solution, 0.1 N hydrochloric acid, water, dilute aqueous potassium bicarbonate, and again water. The methylene chloride solution is dried over anhydrous sodium sulfate and filtered. The filtrate is evaporated to incipient crystallization at room temperature at reduced pressure yield 4.1 gm (90%), m.p. 105°-106°C. 

Halofluorinations take place, as a rule, regioselectively (Markovnikov addition), the olefinic carbons can be substituted with a variety of substituents ranging from alkyl or aryl groups to different electron-withdrawing functions see for example refs 31 and 178-180. Bromo-fluorination of 4-/m-butyl-l-methylcyclohexene with /V-bromosuccinimide in 70% hydrogen fluoride/pyridine gave two stereoisomers 1 and 2.181... 

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