Nitrobenzoyl chloride

The liquid phosphorus oxychloride, b.p. 107°, is a by-product and is removed by fractional distillation under normal pressure. Unless the b.p. of the acid chloride differs very considerably (say, ] 100°) from that of the phosphorus oxychloride, the acyl halide is liable to contain traces of the latter. In such circumstances it is preferable to use thionyl chloride for the preparation of the acid chloride. 

By the action of thionyl chloride upon the acid (see discussion preceding Section 111,86), for example  

It will be noted that the by-products are both gaseous. In practice, a slight excess over the theoretical quantity (20-75 per cent.) of thionyl chloride is used some of this is volatilised with the gaseous by-products and the remainder is easily removed by fractional distillation (thionyl chloride has b.p. 77°). 

The preparation of 3 5-dinitrobenzoyl chloride by both the PCI, and SOCl, methods is described in Section 111,27,1 see also Section VII,22. 

Thionyl chloride method. Mix 100 g. of pure p-nitrobenzoic acid and 125 g. (77 ml.) (1) of redistilled thionyl chloride in a 500 ml. round-bottomed flask. Fit the flask with a double surface reflux condenser carrying a calcium chloride (or cottou wool) guard tube and connect the latter to an absorption device e.g.. Fig. II, 8, c). Heat the flask on a 

Thionyl chloride method. Mix 100 g. of pure p-nitrobenzoic acid and 125 g. (77 ml.) (1) of redistilled thionyl chloride in a 500 ml. round-bottomed flask. Fit the flask with a double surface reflux condenser carrying a calcium chloride (or cottou wool) guard tube and connect the latter to an absorption device (e.g., Fig. II, 8, 1, c). Heat the flask on a water bath with occasional shaking for 1 hour or until the evolution of hydrogen chloride and sulphur dioxide ahnost ceases. Allow the reaction mixture to cool, transfer it cautiously to a Claisen flask connected with a water-cooled condenser and a receiver (compare Fig. II, 13, 1). Distil off the excess of thionyl chloride (b.p. 77°) slowly and continue the distillation until the temperature rises rapidly to about 120° this will ensure that all the thionyl chloride is removed. Allow to cool, and distil the residual p-nitrobenzoyl chloride under diminished pressure as detailed in the Phosphorus Pentachloride Method. The resulting p-nitrobenzoyl chloride (a yellow crystalline solid) weighs 107 g. and melts at 72-73°. 

CAUTION. The preparation of o-nitrobenzoyl chloride, o-nitrophenacetyl chloride and all o-nitroacid chlorides should not be attempted by the above methods a violent explosion may occur upon distilling the product or when the last traces of thionyl chloride are removed in vacuo at 100°. Perhaps the safest method is to treat the pure acid in benzene solution with 1 1 mols of thionyl chloride and to reflux until evolution of sulphur dioxide and hydrogen chloride has ceased the solution of the acid chloride in benzene may then be employed for most reactions. 

A very small high-boiling fraction may remain in the flask this consists largely of benzoic anhydride (b.p. 360° m.p. 42°) produced by the dehydrating action of the thionyl chloride upon the benzoic acid  

N02 CeH4 CO2H+PCI5 - N02 C6H4 COCl+POCla+HCI 

The reaction mixture is now transferred to a Claisen flask connected with a water-cooled condenser, and the phosphorus oxychloride is removed at ordinary pressure by raising the temperature of the oil bath (Note 2) gradually to 200-2 20°. The water condenser is then replaced by a short air-cooled condenser and the residual liquid is distilled under reduced pressure (Note 3). A small quantity of phosphorus oxychloride first distils over, after which the receiver is changed and the temperature rises rapidly to the boiling point of / -nitrobenzoyl chloride, I97°/73 Pirn. (i55°/20 mm.). During this distillation the oil bath should be kept at a temperature of about 230-250° (or at 210 -2150 if 20 111m. pressure is used). The yield is 500-534 g. (90-96 per cent of the theoretical amount). The distillate 

Phosphorus pentachloride purchased as pure is occasionally of inferior quality and gives poor results. It is not a difficult matter to prepare in the laboratory a product suitable for this reaction. To 1000 g. of phosphorus trichloride, chlorine is added until the increase in weight is 500 g. The gas should be added above the surface of the liquid, which is stirred occasionally during the addition. The stirring should not be continuous, however, as this tends to allow the formation of the pentachloride in the tube, which thus becomes clogged. At the end of the reaction the mixture becomes practically solid. 

If the reaction mixture is heated with a free flame during the distillation under reduced pressure, there is considerable danger of superheating and consequent decomposition (sometimes violent) of the -nitrobenzoyl chloride. 

Experience with many preparations of this acid chloride has shown that it is desirable to use, during the distillation under reduced pressure, a safety water-bottle between the receiving flask and the manometer. This avoids the passage of vapors of phosphorus oxychloride or acid chloride into the pump. 

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Nitrobenzoyl chloride and 3,5-dinitrobenzoyl chloride were each reacted with dl-1-phenylethylamine and 4-amino-l-benzylpiperidine using a phase-transfer reaction [23]. The amines were in the aqueous phase and the acid chlorides in the organic phase. By this means, a 2 x 2 library was created in one experimental run. 

P 9] DL-l-Phenylethylamine and 4-amino-l-benzylpiperidine were dissolved in 0.1 M NaOH aqueous solution [23]. 3-Nitrobenzoyl chloride and 3,5-dinitrobenzoyl chloride were used as ethyl acetate solutions. The concentration of all reactants was set to 0.01 M. Syringe pumps served for liquid feed. The flow rate was 50 plmin and room-temperature processing was applied. No further temperature control was exerted as the reaction is only mildly exothermic. After having passed the micro reactor, the phases were settled in test-tubes and the organic phase was withdrawn for analysis. 

Figure 4.40 Dependence of yield on specific interfacial area between aqueous or organic phase. The four combinations AC-BD refer to the respective reactions between dl-1-phenyl-ethylamine (A), 4-amino-l-benzylpiperidine (B), 3-nitrobenzoyl chloride (C), and 3,5-dinitrobenzoyl chloride (D) [23],...

Methanol, Hydrogen, Raney nickel catalyst, 0484 Methoxyacetyl chloride, 1165 4-Methoxy-3-nitrobenzoyl chloride, 2916 Methyl formate, Methanol, Sodium methoxide, 0834 3-Methyl-2-penten-4-yn-l-ol, 2384 Nitric acid, 4436... 

Methoxy-5-nitroaniline, 2802 4-Methoxy-3-nitrobenzoyl chloride, 2916 Methylborylene, 0425 Methyl iminioformate chloride, 0897... 

Also of synthetic significance is the Beckmann fragmentation of cis- and imm>-3-ethoxy-2,2,4-trimethylcyclobutanone oxime (71) with 3-nitrobenzoyl chloride at ambient temperature, from which the bifunctional (2S,3/ )-3-ethoxy-2,4-dimethylpent-4-enenitrile (72 61 %) and (25,3S)-3-ethoxy-2,4-dimethylpent-4-enenitrile (72 64%) are generated with approximately 98 and 91% stereoselectivity, respectively.172 Another condition for such a Beckmann fragmentation is to employ trifluoroacetic anhydride in pyridine and /< r/-butyl methyl ether at temperatures between 20-50 C, which also leads to the formation of the pent-4-enenitriles.172... 

See 4-Methoxy-3-nitrobenzoyl chloride See entry NITROACYL HALIDES... 

Fithium tetrahydroaluminate, Fluoroamides, 0075 Lithium tetrahydroaluminate, Water, 0075 Lithium, 1,2-Diaminoethane, Tetralin, 4675 Magnesium, Barium carbonate, Water, 4685 Maleic anhydride, Bases, or Cations, 1400 Mercaptoacetonitrile, 0763 t Methanol, Hydrogen, Raney nickel catalyst, 0482 4-Methoxy-3-nitrobenzoyl chloride, 2911 Methoxyacetyl chloride, 1161 t Methyl formate, Methanol, Sodium methoxide, 0830 3-Methyl-2-penten-4-yn-l-ol, 2378 Nitric acid, 4430... 

Aluminum chloride 4-Chloro-3-nitrobenzoyl chloride Methyl chloroformate... 

To a stirred and cooled (ice bath) suspension of 25 parts of aluminum chloride in 52 parts of fluorobenzene is added dropwise a solution of 27.5 parts of 4-chloro-3-nitrobenzoyl chloride in 52 parts of fluorobenzene. Upon completion, stirring is continued overnight at room temperature. The reaction mixture is poured onto water and the product is extracted with methylene chloride. The extract is washed successively with sodium hydrogen carbonate solution and water, dried, filtered and evaporated in vacuo. The solid residue is crystallized from 2-propanol, yielding 4-chloro-4 -fluoro-3-nitrobenzophenone MP 97.9°C. 

C6H15N05 1 -amino-1 -deoxy-D-glucitol 488-43-7 25.00 1.1273 2 9534 C7H3CI2N03 4-chloro-3-nitrobenzoyl chloride 38818-50-7 25.00 1.6035 2... 

The Schotten-Baumann reaction of l-naphthylamine-4,6,8-trisulphonic acid (71) with 4-methyl-3-nitrobenzoyl chloride (72) gives the corresponding amide (73),... 

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