Nitro benzyl alcohol

Much more spectacular were the selectivity variations in the case of 3-nitro-benzaldehyde reduction (Table 3). Depending on the hydrogen donor used 3-nitro-benzyl alcohol (methanol, 450°C) or 3-aminobenzaldehyde (i-propanol, 450°C) were the main reaction products. 

Whittaker performed quantitative structure-activity correlation studies and showed that within a series of m-substituted alcohols the rates correlate with Om- Thus the greater reactivity of m-methoxybenzyl alcohol relative to chloro- and nitro-benzyl alcohol is consistent with the electronic properties of the benzylic bond. This would correspond to hydrogen atom transfer as a key mechanistic step (see below). 

These chemists first examined the reaction of 1 with a primary alcohol, p-nitro-benzyl alcohol (6). The reaction in acetonitrile and with added triethylamine (3 equiv.) gives the t,3-dioxolanc-4-one 7 in 84%, yield. The reaction in pure triethylamine gives the crystalline ester 8 in 47%, yield. 

The possibility of applying the electron-spin-resonance technique to the study of free-radical intermediates in organic electrode reactions was also investigated by the American Oil Company. Studies using stable free radicals (e.g., from p-amino phenol) gave an indication of optimum conditions for detection. However, application of these conditions to the search for anodical-ly generated radicals from benzyl alcohol, t-butanol, and p-nitro benzyl alcohols did not produce observable ESR signals. It is felt that further attempts in this direction will be worth while. 

Hexadecylpyridinium bromide (Mj 385 hexadecylpyridinium = 304) in 2-nitro-benzyl alcohol... 

Drop 1 g. of sodium into 10 ml. of ethyl alcohol in a small flask provided with a small water condenser heat the mixture until all the sodium has dissolved. Cool, and add 1 g. of the ester and 0-5 ml. of water. Frequently the sodium salt of the acid will be deposited either at once or after boiling for a few minutes. If this occurs, filter oflF the solid at once, wash it with a little absolute ethyl alcohol (or absolute methylated spirit), and convert it into the p-bromophenacyl ester, p-nitro-benzyl ester or S-benzyl-tso-thiuronium salt (for experimental details, see Section 111,85). If no solid separates, continue the boiling for 30-60 minutes, boil oflF the alcohol, allow to cool, render the product just neutral to phenolphthalein with dilute sulphuric or hydrochloric acid, convert the sodium salt present in solution into a crystalline derivative (Section 111,85), and determine its melting point. 

Benzyl saUcylate can be prepared by the reaction of ben2yl chloride with an alkaU salt of saUcyhc acid at 130—140°C or by the transesterification of methyl saUcylate with benzyl alcohol. It is used as a fixative and solvent for nitro musks and as a fragrance for detergents. Benzyl saUcylate was priced at... 

Lower aliphatic primary alcohols including octanol, halogeno alcohols, and benzylic alcohols yield only alkyl fluorides [81, 82 The reaction of higher primary alcohols gives a mixture of fluorides and alkyl 2,3,3,3-tetrafluoropropionates [S3] and 2-nitro alcohols, alcohols branched at C-2 [82, 84 and unsaturated alcohols [55] give 2,3,3,3-tetrafluoropropionates exclusively... 

Synthetic routes that access appropriately substituted thienobenzazepines are also quite important for medicinal chemistry stracture activity relationship studies, and many involve similar bond connectivity strategies. One notable example employs the use of conunercially available 4-methyl-3-nitrophenol (Scheme 6.3). Methylation of the phenol followed by bromination, hydrolysis, and oxidation of the benzylic alcohol afforded aldehyde 9 in quantitative yield. Treatment of this aldehyde with 5-lithio-2-methylthiophene provided, after dehydroxylation, nitro intermediate A in good overall yield. Reduction of the nitro functionality and treatment with phosgene presented the corresponding isocyanide which upon cychzation using aluminum trichloride in a Friedel-Crafts fashion afforded the... 

Ono and Kamimura have found a very simple method for the stereo-control of the Michael addition of thiols, selenols, or alcohols. The Michael addition of thiolate anions to nitroalkenes followed by protonation at -78 °C gives anti-(J-nitro sulfides (Eq. 4.8).11 This procedure can be extended to the preparation of a/jti-(3-nitro selenides (Eq. 4.9)12 and a/jti-(3-nitro ethers (Eq. 4.10).13 The addition products of benzyl alcohol are converted into P-amino alcohols with the retention of the configuration, which is a useful method for anri-P-amino alcohols. This is an alternative method of stereoselective nitro-aldol reactions (Section 3.3). The anti selectivity of these reactions is explained on the basis of stereoselective protonation to nitronate anion intermediates. The high stereoselectivity requires heteroatom substituents on the P-position of the nitro group. The computational calculation exhibits that the heteroatom covers one site of the plane of the nitronate anion.14... 

These reaction conditions also permit the chemoselective quantitative reduction of benzaldehyde to benzyl alcohol without any concomitant reduction of either acetophenone or 3,3-dimethylbutan-2-one present in the same reaction mixture.83 Additionally, this useful method permits the reduction of aldehyde functions in polyfunctional compounds without affecting amide, anhydride, eth-ylenic, bromo, chloro, or nitro groups.79,80,319... 

Chemical/Physical. Products identified from the reaction of toluene with nitric oxide and OH radicals include benzaldehyde, benzyl alcohol, 3-nitrotoluene, p-methylbenzoquinone, and o, m, and p-cresol (Kenley et ah, 1978). Gaseous toluene reacted with nitrate radicals in purified air forming the following products benzaldehyde, benzyl alcohol, benzyl nitrate, and 2-, 3-, and 4-nitro-toluene (Chiodini et al., 1993). Under atmospheric conditions, the gas-phase reaction with OH radicals and nitrogen oxides resulted in the formation of benzaldehyde, benzyl nitrate, 3-nitrotoluene, and o-, m-, and p-cresol (Finlayson-Pitts and Pitts, 1986 Atkinson, 1990). 

Y = OMe and 1.18 for 115, Y = Ph, in accordance with the change in hybridization at the benzylic position in the transition state (118). Furthermore, in H2 0, the Diels-Alder product (120) from cyclopentadiene and 119 was unlabelled while benzyl alcohol (122), formed from 121 and water, was enriched in 0. Methyl and nitro analogues (115,... 

Recently, Behiman and coworkers discussed the mechanism of the Elbs oxidation reaction and explained why the para product predominates over the ortho product in this oxidation. According to the authors, semiempirical calculations show that the intermediate formed by the reaction between peroxydisulfate anion and the phenolate ion is the species resulting from reaction of the tautomeric carbanion of the latter rather than by the one resulting from the attack by the oxyanion. This is confirmed by the synthesis of the latter intermediate by the reaction between Caro s acid dianion and some nitro-substituted fluorobenzenes. An example of oxidative functionalization of an aromatic compound is the conversion of alkylated aromatic compound 17 to benzyl alcohols 20. The initial step in the mechanism of this reaction is the formation of a radical cation 18, which subsequently undergoes deprotonation. The fate of the resulting benzylic radical 19 depends on the conditions and additives. In aqueous solution, for example, further oxidation and trapping of the cationic intermediate by water lead to the formation of the benzyl alcohols 20 (equation 13) . ... 

Problem 19,14 Assign numbers from 1 for least to 4 for most to indicate the relative acid strengths in the following groups (a) phenol, m-chlorophenol, m-nitrophenol, m-cresol (b) phenol, benzoic acid, p-nitro-phenol, carbonic acid (c) phenol, p-chlorophenol, p-nitrophenol, p-cresol (d) phenol, o-nitrophenol, m-nitrophenol, p-nitrophenol (e) phenol, p-chlorophenol, 2,4,6-trichlorophenol, 2,4-dichlorophenol (/) phenol, benzyl alcohol, benzenesulfonic acid, benzoic acid. ... 

When sodium methylate or ethylate was prepared by direct reaction of sodium with an excess of alcohols and the resulting mixture was used as a dispersion in benzene to reduce aromatic nitro compounds, yields of azoxy compounds were quite low. With the higher alcohols, substantial production of azoxy compounds was observed. However, the reduction product mixture usually contained a 40 % yield of amino compounds. In a few examples, where benzyl alcohol was used to prepare sodium benzylate, only azoxy products and no amino by-products were formed. The scope of this preparation requires further study. 

Alcoholic potassium hydroxide and sodium alcoholate in the presence of alcohols such as benzyl alcohol have been used as reducing agents for aromatic nitro compounds. 

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