Nitro, acids benzaldehyde

The data for this solvent were not used to calculate the parameters in Table 54. Similarly the data for decarboxylation of oxanilic acid in anisole were not used for the AH -AS correlation. With the reported AH value of 32.6 kcal.mole , the entropy of activation is calculated to be 3.59 0.03 eu compared to the reported value of 11.1 eu. In the decarboxylation of malonic acid, the data obtained with pyridine and ) -mercaptopropionic acid solvents deviated considerably from the plots and were not included in the correlation. The data for malonic acid decarboxylation appeared to be best correlated by two lines. One line was described by the following solvents acids, phenols, nitro-aromatics, benzaldehyde, and the melt the other line involved amines, alcohols, dimethylsulfoxide and triethyl phosphate. The latter line was not as well defined as the former. However, it was our intention to correlate as many solvents as possible with a minimum number of lines. The data for decarboxylation of malonic acid in water and in benzyl alcohol fell between these two lines and were not included in either correlation. The data for decarboxylation of benzylmalonic acid also appeared to be best correlated with two lines. One line was defined by the cresols, acids and the melt, while the other line was defined by the amines. Decarboxylation of cinnamalmalonic acid was correlated by two lines as indicated in Table 54. Similarly j8-resorcylic acid was correlated by two lines. The separation of data into parallel lines is presumably due to multiple solvation mechanisms . In support of this interpretation it is seen that when two lines are observed, acids fall into one line and amines into the other. It is not unexpected that the solvation mechanisms for these two classes of solvents would differ. It is interesting to note that all of the nitrogen containing acids are correlated reasonably well with one line for both basic and acidic solvents. Also the AHq values fall in a rather narrow range for all of the acids. From the values of p in Table 54, there appears to be little correlation between this parameter and the melting point of the acids, contrary to prior reports " ... 

The reaction mechanism of Lehmstedt-Tanasescu reaction is generally based on an aromatic electrophilic addition of an or/Ao-nitro-substituted benzaldehyde to electron-rich arenes, yielding substituted 3-phenyl 1,2-benzisoxazoles, which are then rearranged to the desired acridones. In the first step of the reaction mechanism the benzaldehyde is protonated by sulfuric acid to form intermediate 5, followed by electrophilic addition to an electron rich arene (benzene in the following scheme), to give compound 6. Intramolecular attack of the formed hydroxyl group to the or/to-positioned... 

Nearly all of the benzal chloride produced is consumed in the manufacture of benzaldehyde. Benzaldehyde (qv) is used in the manufacture of perfume and flavor chemicals, dyes, and pharmaceuticals. The principal part of benzotrichloride production is used in the manufacture of benzoyl chloride (see Benzoic acid). Lesser amounts are consumed in the manufacture of benzotrifluoride, as a dyestuff intermediate, and in producing hydroxybenzophenone ultraviolet light stabilizers. Benzotrifluoride is an important intermediate in the manufacture of herbicides, pharmaceuticals, antimicrobial agents, and the lampreycide, 4-nitro-3-(trifluorometh5l)phenol [88-30-2]. 

In 1972, van Leusen, Hoogenboom and Siderius introduced the utility of TosMIC for the synthesis of azoles (pyrroles, oxazoles, imidazoles, thiazoles, etc.) by delivering a C-N-C fragment to polarized double bonds. In addition to the synthesis of 5-phenyloxazole, they also described reaction of TosMIC with /7-nitro- and /7-chloro-benzaldehyde (3) to provide analogous oxazoles 4 in 91% and 57% yield, respectively. Reaction of TosMIC with acid chlorides, anhydrides, or esters leads to oxazoles in which the tosyl group is retained. For example, reaction of acetic anhydride and TosMIC furnish oxazole 5 in 73% yield. ... 

In 212 cc of water are mixed 21.2 grams (0.112 mol) of N-(benzylidene)-3-amino-2-oxa-zolidone, 8.93 grams of concentrated sulfuric acid, and 30.1 grams (0.124 mol) of 5-ni-tro-2-furaldehyde diacetate. This mixture is heated to effect the hydrolysis of N-(benzy-lidene)-3-amino-2-oxazolidone, steam distillation of the benzaldehyde and hydrolysis of 5-nitro-2-furaldehyde diacetate. Approximately IV2 hours are required for this reaction to take place. When the bulk of the benzaldehyde has been removed, 50 cc of 99% isopropanol are added, the reaction mixture is refluxed a short time, and the crystals of N-(5-nitro-2-furfurylidene)-3-amino-2-oxazolidone are filtered from the hot suspension. The product is washed with water and isopropanol and dried a yield of 23.3 grams, 92.8% based on N-(benzylidene)-3-amino-2-oxazolidone of MP 254° to 256°C is obtained, according to U.S. Patent 2,759,931. 

Using 2,6-diformyl-4-methylphenol dioxime, Tasker, Schroder, and their co-workers conducted a magnetostructural study on complex (374) (pseudo macrocyclic structure Cu-Cu 2.994 A 2J= — 904 cm-1).330 Using 2-hydroxy-5-nitro-benzaldehyde benzoylhydrazone as ligand, complex (375) (Cu-Cu 3.041 A 2J=—372cm 1) was reported.331 Using 3-formylsalicylic acid oxime Okawa and co-workers reported complex (376) (square-planar and SP geometry Cu-Cu 2.961 A).332... 

A. tn-NUrocinnamic acid. In a 1-1. round-bottomed flask fitted with a reflux condenser are placed 151 g. (1 mole) of tw-nitro-benzaldehyde (Note 1), 115 g. (1.1 moles) of malonic acid, 250 ml. of 95% ethanol, and 25 ml. of pyridine. The mixture is heated on a steam bath under gentle reflux for 6-8 hours and cooled. The large masses of crystals are broken up with a spatula, and the reaction mixture is cooled in an ice bath. The solid is collected on a Buchner funnel, and the residue is washed with 100 ml. of cold ethanol and then with two 100-ml. portions of diethyl ether. The crude w-nitrocinnamic acid is suspended in 300 ml. of ethanol and digested on a steam plate for 2-3 hours. The mixture is cooled and filtered, and the solid is air-dried. The product, 144 155 g. (75-80%), is a light-yellow solid and melts at 200-201° (Note 2). 

Nitro compounds have also been reported to undergo photocyclizations. The intermediacy of an isoxazoline in the photorearrangement of o-nitro-benzaldehyde to o-nitrosobenzoic acid is now in doubt,318 but intramolecular hydrogen abstraction by an excited nitro group in nitrobenzene derivatives can result in the formation of heterocycles. 4-tm-Butyl-3-methoxy-2,6-dinitrotoluene (384) on irradiation in methanolic sodium hydroxide solution... 

I. Condensation of N-Monosubstituted Hydroxylamines with Carbonyl Compounds Condensation of N -monosubstituted hydroxylamines with carbonyl compounds is used as a direct synthesis of many acyclic nitrones. The synthesis of hydroxylamines is being carried out in situ via reduction of nitro compounds with zinc powder in the presence of weak acids (NH4CI or AcOH) (14, 18, 132). The reaction kinetics of benzaldehyde with phenylhydroxylamine and the subsequent reaction sequence are shown in Scheme 2.21 (133). 

Mix 0.25M substituted benzaldehyde, 0.3M nitroethane, 50 ml dry toluene and 5 ml n-butylamine (or other amine), and reflux 3 hours with a Dean-Stark trap (or prepare the nitro-propene as described elsewhere here). Add 50 g iron powder and 1 g FeCl3 optional) and reflux while adding 90 ml concentrated HCI over 3 hours. Reflux 1 hour more, add 2 liters of water and extract 3 times with ether, then dry and evaporate in vacuum (or steam distill until about 3.5 liters of distillate is obtained extract the distillate 3 times with toluene wash the toluene layers with 7 g NaHS03 in 225 ml of water, then 3 times with water and dry, evaporate in vacuum) to get the ketone. Mix 0.13M ketone, 28 g formamide (or dimethyl-formamide if the N.N-dimethylamine is desired) and 3 ml formic acid and heat at 160°. Add 3 more ml formic acid and heat 16 hours at 170-180° adding formic acid from time to time to keep the pH acid. Distill off the water formed (about 16 ml), cool and extract with 3X70 ml benzene. Distill off the benzene and reflux the residue 7 hours with 30 ml concentrated HCI. Chill, basify with 10% NaOH and extract with 3X70 ml ether. Dry and evaporate the ether in... 

For the reduction of nitro-compounds containing a group which may be attacked by nascent hydrogen, as, for example, an aldehyde group, an unsaturated side chain, and so on, special methods must he applied. In such cases ferrous hydroxide or iron powder (cf. Chap. VII. 5, arsanilic acid) are often used. The reduction is carried out thus a weighed amount of ferrous sulphate is caused to act, in the presence of alkali (potassium or sodium hydroxide, baryta), on the substance to he reduced. In this way it is possible to reduce, for example, o-nitro-benzaldehyde to aminobenzaldehyde, and o-nitrocinnamic acid to amino-cinnamic acid. 

Photolytic. Synthetic air containing gaseous nitrous acid and toluene exposed to artificial sunlight (Z = 300-450 nm) yielded methyl nitrate, peroxyacetal nitrate, and a nitro aromatic compound tentatively identified as a nitrophenol or nitrocresol (Cox et al., 1980). A n-hexane solution containing toluene and spread as a thin film (4 mm) on cold water (10 °C) was irradiated by a mercury medium pressure lamp. In 3 h, 26% of the toluene photooxidized into benzaldehyde. 

Benzaldehyde, 4-(l, l-dimethylethyl)-3-nitro Benzaldehyde, 4-(l, l-dimethylethyl)-3,5-dinitro Benzene, 2-(l,l-dimethylethyl)-4,5 dimethyl-1, 3-dinitro Benzoic acid, 4-(l,l-dimethylethyl)-2methyl 3,5-dinitro Benzene, l(l,l-dimethylethyl)-3,4-dimethyl-6- (lmethylethyl)-... 

Nitro and Other Derivatives of Benzoic Acid Mononitrobenzoic AcidfMNBAc), 02N.C6H4.CO-OH mw 167.12, N 8.38%, OB to C02-ll9.7%. Three isomers are described in the literature 2-Nitrobenzoic Acid, col ndls(from w), mp 144 -8° Q 730-735kcal/mol(Refs 1 6) 3-Nitro-benzoic Acid, monoclinic yel prisms, mp 140-1° Q 729kcal/mol(Refs 2 5) Nishi Toki(Ref 4) investigated a number of methods of its prepn from benzaldehyde and noted that reaction with nitric -sulfuric acid mixts above 100° led to explosions 4-Nitrobenzoic Acid, lfts(from boiling w), mp 238 -40° QP 728kcal/mol(Ref 3)... 

An intramolecular Mannich-type cyclization of l,3-dimethyl-6-(2-aminophenylthio)uracil (120) has been utilized for the synthesis of 5, 6-dihydropyrimido[4,5-b][ 1,5]benzothiazepine-2,4( 1H,3//)-diones (121) this synthesis was realized by reaction of 120 with an excess of formaldehyde, benzaldehyde, or p-nitro- or p-methoxybenzaldehyde in chloroform in the presence of a catalytic amount of p-toluenesulfonic acid under reflux for 4-10 hours. The thiazepine cyclization using aliphatic aldehydes other than formaldehyde did not give satisfactory results. In these cases the reaction resulted in the formation of a dimeric product that probably... 

Participation of proton-donors other than hydroxonium ion has been observed, e.g. for phenylglyoxylic (59) and pyruvic (60) acids, for substituted benzaldehydes (61—63), unsaturated acids (49, 64), N-nitros-amines (65), nitrones (66), unsaturated ketones (67), aryl alkyl ketones (68) and various heterocyclic compounds (69, 70). Consecutive dissociation has been observed for maleic and fumaric acids (48), for phthalic acid (50) and for pyridoxal derivatives (71). 

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