P-Nitrobenzyl bromide

Dicbloronitrobenzene o-Nitrobenzyl chloride m-Nitrobenzyl chloride p-Nitrobenzyl chloride o-Nitrobenzyl bromide m-Nitrobenzyl bromide p-Nitrobenzyl bromide o-Nitrobenzyl iodide m-Nitrobenzyl iodide p-Nitrobenzyl iodide o-Nitrobenzyl cyanide... 

Care must be taken in manipulating the lachrymatory solutions of p-nitrobenzyl bromide. If the substance should come into contact with the skin, bnthe the affected part with alcohol. 

A mechanism of this type permits substitution of certain aromatic and ahphatic nitro compounds by a variety of nucleophiles. These reactions were discovered as the result of efforts to explain the mechanistic basis for high-yield carbon alkylation of the 2-nitropropane anion by p-nitrobenzyl chloride. p-Nitrobenzyl bromide and iodide and benzyl halides that do not contain a nitro substituent give mainly the unstable oxygen alkylation product with this ambident anion ... 

We first tried to prepare 1-hydroxyyohimbine (23) and its derivatives. With 23 in hand (as described in Section II.D), its methylation with CH2N2 is carried out to provide 1-methoxy derivative 304 (77%) (Scheme 47). Utilizing K2CO3 as a base in DMF, allyl bromide, butyl iodide, and p-nitrobenzyl bromide react successfully with 23, resulting in the formation of 305 (93%), 306 (99%), and 307 (90%), respectively. All of these compounds, including 23 itself, are found to exhibit potent Q 2-blocking activity (2001H1237), and the details will be reported in due course. 

Reslurrying can sometimes be advantageously employed for removal of impurities adsorbed on the surface. Anderson (2000) has given an example of the removal of excess p-nitrobenzyl bromide from a modified penicillin by reslurrying. 

Bromoadamantane and 1-bromoadamantane are reduced to adamantane in yields of 84% and 79%, respectively, when treated with triethylsilane and catalytic amounts of aluminum chloride.186 Similar treatment of benzhydryl chloride and exo-2-bromonorbomane gives the related hydrocarbons in yields of 100% and 96%, respectively.186 In contrast, 2-bromo-l-phenylpropane gives only a 43% yield of 1-phenylpropane the remainder consists of Friedel-Crafts alkylation products.186 Some alkyl halides resist reduction by this method, even when forcing conditions are employed. These include p-nitrobenzyl bromide, 3-bromopropanenitrile, and 5-bromopentanenitrile.186... 

Sodium fluoroacetate.1 To methyl fluoroacetate (46-0 g., 0-5 mol.) suspended in water (100 c.c. containing a few drops of phenolphthalein) sodium hydroxide (0-5 mol., 20 g. in 100 c.c. water) is added slowly. The mixture is kept well stirred, and the rate of addition governed by the disappearance of the red coloration. When the addition of sodium hydroxide is complete, a few more drops of M.F.A. are added to render the solution acid. It is then evaporated on the water-bath until crystallization starts, cooled and the solid filtered off. More solid is obtained from the filtrate by the addition of alcohol total yield 45-5g. (91-0 per cent). (Found F, 19-0. Calc, for C2H202FNa F, 19-0 per cent.) This is characterized as p-nitrobenzyl fluoroacetate as follows. p-Nitrobenzyl bromide (0-9 g.), dissolved in alcohol (10 c.c.), is added to a solution of sodium fluoroacetate (0-3 g.) in the minimum amount of water. The mixture is heated under a reflux condenser for 2 hr. and allowed to cool the solid is collected by filtration, and crystallized from ethanol as long needles, m.p. 76°. 

Second-order rate constants have been measured for the S 2 reactions of benzyl bromide and p-nitrobenzyl bromide with hydroxy nucleophiles. The values of (HOO )//c(HO ) are very small (1.3 and 1.2, respectively) for the two substrates. Thus the a-effect is very small and it is suggested that this may be due to the lack of tight a-bond formation at the transition state. 

H2.C(N02)3 mw 286.16, N 19.58% crysts (fron ale + CC14), mp 135°. It may be prepd from p-nitrobenzyl bromide and silver nitroform (from silver oxide and nitroform) in ether for 50 hours. 

Poly(/ -acetamidostyrene) (V) is prepared from p-nitrobenzyl bromide as shown in Scheme 6. Homopolymer V has very little solubility in common organic solvents and thus it is difficult to use attempts at increasing the solubility of V by incorporation of up to 40% styrene units in copolymers such as Va do not result in any significant improvement in solubility. Polyfphenyl methacrylate) (VI) and poly(methacryl anilide) (VII) are prepared from the corresponding monomers according to literature procedures (19-20). 

Preparation of p-Nitrostyrene The monomer p-Nitrostyrene was prepared by the procedure of Broos and Anteunis (27) using p-nitrobenzyl bromide as starting material. The crude monomer was purified by column chromatography using a 9 1 hexane/ethyl acetate mixture as eluting solvent to yield 78% of p-nitrostyrene. 

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