P-bromoanisole

Dimethyl sulfate (38.4 g., 0.30 mole) is added slowly (Caution— toxic substance) with stirring to a solution of 44 g. (0.26 mole) of m-bromophenol (p. 54) in 107 g. of a 10% aqueous solution of sodium hydroxide. Stirring is continued until the reaction mixture is neutral. The organic layer is separated by ether extraction, and the ethereal solution is dried. Distillation gives a colorless oil, b.p. 209-212°/752 mm. This is redistilled and 35 g. (73%) of m-bromoanisole is collected at 210-211°. 

Bromine (310 g., 1.94 moles) is introduced into a cooled solution of 200 g. (1.85 moles) of anisole in 750 g. of glacial acetic acid by passing a stream of air through the bromine and then into the reaction flask containing the anisole-acetic acid solution. (Hood.) After introduction of the bromine, the acetic acid solution is a light-yellow 

A solution of 5 ml. of bromine in 100 ml. of carbon bisulfide is added dropwise to a suspension of 18 g. (0.10 n le) of anthracene in 200 ml. of carbon bisulfide. The reaction mixture is cooled with ice during the addition. The precipitated solid is removed by filtration and washed with cold carbon bisulfide and cold ether. The resulting anthracene dibromide weighs 32 g. 

A mixture containing 50 g. (0.15 mole) of anthracene dibromide, 250 ml. of toluene, and 0.5 g. of phenol is allowed to stand for 4 days in a flask protected from the atmosphere with a calcium chloride tube. The reaction mixture is heated slowly to 50° and after 2 hours at this temperature is heated on a boiling water bath for 30 minutes. The toluene is removed by steam distillation, and the resulting solid is recrystallized from 1250 ml. of ethanol to give a 94% yield of 9-bromo-anthracene, m.p. 98-99°. A product melting at 100-101° is obtained in 55% yield by distillation under reduced pressure followed by five recrystallizations from petroleum ether (b.p. 90-100°) and one from a large volume of ethanol. 

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A) Preparation of p-Hydroxy-p -Methoxybemhydrylidenecyclohexane To a Grignard solution prepared from 110 g of magnesium (4.5 mols) and 840 g of p-bromoanisole (4.5 mols) in one liter of anhydrous ether, there was added dropwise with vigorous agitation 307 g of p-hydroxyphenyl cyclohexyl ketone (1.5 mols) dissolved in one liter of anhydrous ether. Upon completion of the addition the reaction mixture was refluxed for 2.5 hours with agitation, and was then cooled. Thereupon 15 mols of ammonium chloride dissolved in 3 liters of water were added. The ethereal layer was separated, washed with water, dried over anhydrous sodium sulfate and distilled. Yield 370 g. BP 180° to 190°C at 0.1 mm. The substance was recrystallized from a mixture of carbon tetrachloride and petroleum ether. MP 145° to 146°C. 

Timolol maleate a-Bromoacetophenone Nomifensine maleate Bromoacetyl bromide Bromazepam Cephapirin sodium Clonazepam Flunitrazepam 5-Bromoacetyl salicylamide Labetalol HCI m-Bromoanisole Tramadol HCI p-Bromoanisole Cyclofenil Bromobenzene... 

The reaction of anisole with copper(II) bromide in benzene at 50°C yielded no detectable products after 10 h. In contrast, in a similar reaction using alumina-supported copper(II) bromide, p-bromoanisole in 90 % yield was obtained from the reaction run at 30°C for 2 h. (eqn. 1). No dibromides were detected. 

Time-resolved spectroscopy establishes that the 25-ps laser irradiation of the relatively persistent charge-transfer complex of p-bromoanisole with iodine monochloride generates the contact ion pair (see Fig. 15b) in which the metastable ICP undergoes mesolytic fragmentation to form the reactive triad, i.e.,... 

Freshly distilled THF (200 ml) and magnesium turnings (25.2 g, 1.0 mol) were added to a flame-dried, 2-1 flask equipped with a 500-ml dropping funnel. Then, p-bromoanisole (5.0 ml, 40 mmol) was added. After the Grignard reaction initiated, additional p-bromoanisole (96.0 ml, 0.77 mol) was added over 1 h. The flask contents were then stirred for 1 h at room temperature, and subsequently phenyldichlorophos-phine (68.02 g, 0.38 mol) was slowly injected into the stirred mixture. The reaction mixture was stirred for 1 h and then poured into a... 

Bis(p-methoxyphenyl) ditelluride (typicalprocedure To a solution of p-methoxyphenyl-magnesium bromide (prepared from p-bromoanisole (5.82 g, 0.0311 mol) and Mg (1.0 g, 0.042 mol) in THF (20 mL)) is added Te shot (3.81 g, 0.0300 mol) at room temperature. The mixture is stirred under reflux for 3 h and then cooled to 0°C and treated with a sam-rated solution of NH Cl (20 mL vigorous evolution of gas). The mixture is filtered through Celite and the solids washed with saturated solution of NH Cl and ether. The organic phase is washed with brine and dried with Na2S04. Evaporation of the solvent and recrystaUiza-tion from CHClj/petroleum ether affords the pure product (5.16 g (75%) m.p. 57-59°C). 

Phenyl n-propyl et.her. Phenyl n-butyl ether o-Cresyl methyl ether (1) m-Cresyl methyl ether. p-Cresyl methyl ether. o-Cresyl ethyl ether m-Cresyl ethyl ether p-Cresyl ethyl ether Benzyl methyl ether Benzyl ethyl ether Methyl a-naphthyl ether Methyl p-naphthyl ether Ethyl a-naphthyl ether Ethyl p-naphthyl ether Benzyl a-naphthyl ether Benzyl P-naphthyl ether o-Methoxydiphenyl p-Methoxydiphenyl. o-Chloroanisole. m-Chloroanisole. p-Chloroanisolc o-Bromoanisole m-Bromoanisole. p-Bromoanisole. o-Iodoanisole m-Iodoanisole p-Iodoanisole o-Nitroanisole... 

The following couples were tested p-chlorobenzonitrile/p-chloro-acetophenone, p-chloroacetophenone/p-chlorodiphenyl, p-chlorodiphenyl /chlorobenzene, p-chlorodiphenyl/p-chlorofluorobenzene, chlorobenzene /p-chlorotoluene, chlorobenzene/p-chloroanisole, p-chloroacetophenone/ methyl ester of m-chlorobenzoic acid, chlorobenzene/m-chlorotoluene, p-chlorodiphenylether/p-chlorotoluene, m-chlorodiphenylether/chloroben-zene, m-chlorodiphenylether/p-chlorotoluene, chlorobenzene/methyl ester of m-chlorobenzoic acid, chlorobenzene/p-bromoanisole, p-bromoaceto-phenone / p-chlorobenzonitrile, p-bromobenzonitrile / p-chloroacetophe-none, bromobenzene/p-chlorodiphenyl, m-bromotoluene/chlorobenzene, and p-chlorodiphenyl/p-bromotoluene. 

The following materials were used in the preparation of the various silanes. The magnesium turnings and anhydrous diethylether were supplied by Fisher Scientific. Bromobenzene and the substituted bromobenzenes, p-bromochloro-benzene, p-bromotrifluoromethylbenzene, p-bromotoluene and p-bromoanisole, were supplied by Aldrich Chemical Co. and used as provided after the purity was checked by GC analysis. The diethoxydimethylsilane was supplied by Petrarch Systems. 

In 2001, Cammidge et al. [47] reported the preparation of an MIP for Suzuki cross-coupling between p-bromoanisole (68) and phenyl-boronic acid (69) to give the corresponding 4-methoxy-biphenyl (70). 

In a related study, bromoanisoles were reacted with excess CHsF-SbFs and the dicationic product 250 was only formed with p -bromoanisole.82 NMR studies indicated that the dication is in equilibrium with the oxonium monocation 249 (eq 85). 

Bromo-2-isopropylanisole (191) was prepared from p-bromoanisole (190). It was caused to react with magnesium and ethylene oxide to obtain the alcohol (192). Its bromoderivative on heating with diethylmalonate and sodium ethoxide followed by hydrolysis with alcoholic potassium hydroxide yielded the substituted malonic acid. This on heating furnished acid (193). Its acid chloride in benzene underwenr cyclization with aluminium chloride to yield tetralone (194). It was... 

When the haloarene radical anion fragments rapidly, and close to the Na(Hg) surface, only dehalogenation was obtained. However, by using benzonitrile as a redox catalyst, good yields of substitution were found. Thus, the reaction of p-bromoanisole with Ph2P ions and benzonitrile gave 85% of the substitution product. 

Similar substitutions are obtained with the carbanions of esters [129, 131], /V,7V-disubstituted amides [137-138] and nitriles [139-140]. The anion of cyclohexylideneacetonitrile reacts with p-bromoanisole exclusively at the y position (Scheme 26) [141]. The ambient anions of phenols and anilines react as carbon nucleophiles, as observed in the reactions of halobenzenes with 2-naphthylamine [142], 2-naphthol [143] and various phenols (Scheme 27) [144-145],... 

Replace the funnel with the two-way Claisen adaptor fitted with reflux condenser and dropping funnel containing the p-bromoanisole (56.1 g). Place the argon inlet on top of the reflux condenser and close the side neck of the flask with a septum. 

To start the reaction, add rapidly a few drops of p-bromoanisole on to the stirred lithium suspension and heat the flask with a heat gun. Once the reaction has started (gas evolution) add the remaining p-bromoanisole dropwise at such a rate that the ether boils gently. At the end of the addition, place an oil bath under the flask and continue the stirring and heat under reflux for a further 15 min. 

A particularly straightforward way to circumvent the problems with catalyst recycling or the formation of palladium black from the homogeneous Pd catalysts is to use Pd on charcoal. This has been pioneered by IMI/Bromine Co Ltd for the industrial production of the UV-B sunscreen 2-ethylhexyl-p-methoxy-cin-namate (Scheme 5.51). At high temperatures p-bromoanisole is treated with 2-ethylhexylacrylate to yield the desired product and some side products - most likely due to the 180-190 °C reaction temperature. It is not quite clear what the actual catalytic species is [73, 95]. It can be assumed that separate Pd atoms that are released from the carrier at the elevated temperature are the catalytically active species. 

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