Sodium Cone production

Diethyl oxalate (29.2 g, 0.20mol) and 4-bromo-2-nitrotoluene (21.6 g, O.lOmol) were added to a cooled solution of sodium cthoxide prepared from sodium (4.6 g, 0.20 mol) and ethanol (90 ml). The mixture was stirred overnight and then refluxed for 10 min. Water (30 ml) was added and the solution refluxed for 2h to effect hydrolysis of the pyruvate ester. The solution was cooled and concentrated in vacuo. The precipitate was washed with ether and dried. The salt was dissolved in water (300 ml) and acidified with cone. HCl. The precipitate was collected, washed with water, dried and recrystallizcd from hexane-EtOAc to give 15.2 g of product. 

A mixture of a-naphthol 41 (15.0 g, 0.1 mol), phenylhydrazine 42 (11.0 g, 0.1 mol) and sodium bisulfite solution (36 %, 250 g) was heated at reflux for 15 h. A further 4 g of phenylhydrazine was added and heating continued for 15 h, after which time the majority of the a-naphthol was consumed. After cooling, the mixture was extracted with ether. The oily, ether and aqueous insoluble residue was warmed with cone. HCl until a dark crystalline mass developed. After cooling, the mixture was extracted with ether. The organic extract was dried and concentrated to afford a crystalline residue which was purified by recrystallisation from ethanol to afford the product 43 as a white crystalline solid, mp 225 °C. A reaction yield is not given. 

A methanolic solution of a V-alkyl-2-nitroaniline (13.3 mmol) was hydrogenated at 20 C and atmospheric pressure in the presence of Raney nickel, filtered and treated with coned HCI (1.32 mL, 13.3 mmol), followed by sodium dicyanimide (1.17 g, 13.1 mmol) in H20 (5 mL). The mixture was heated in an open vessel on a steam bath for 1 h, by which time most of the McOH had evaporated. The resulting suspension of a black oil was treated with a solution of picric acid (6.0 g, 26.2 mmol) in MeOH, whereupon the dipicrate of the product separated as yellow crystals. 

Dichloroethylene in contact with solid caustic alkalies or their cone, solutions will form chloroacetylene which ignites in air [1], Distillation of ethanol containing 0.25% of the halocarbon with aqueous sodium hydroxide gave a product which ignited in air [2]. 

Keto-4-N-methyl-N-acetonylamino-l,2,2a,3,4,5-hexahydrobenzindole. 20 g of the above product is dissolved in a mixture of 250 ml of coned HCl add and 250 ml of water, and the solution is kept under nitrogen for 5 days at 37°. Cool the mixture, treat with carbon, filter, and concentrate the filtrate in vacuo to a small volume. Treat the residue with an excess of sodium bicarbonate, extract with cold chloroform, and remove the chloroform by evaporation in vacuo at room temp. The crude diketone is powdered, slurried with 75 ml of Vi benzene-ether, and filtered. Yield 9.8 g, mp 105-107°. 

B. 7-Fluoroisatin (3). A 250-mL, three-necked, round-bottomed flask fitted with a condenser and a thermometer is charged with 100 mL of coned sulfuric acid. After heating to 70°C, 30.0 g (0.165 mol) of anilide 2 (Note 9) is added over a period of 1 hr. The resulting deep red solution is heated to 90°C (Note 10) for 60 min (Note 11) and then is cooled to room temperature (20°C) over an ice bath (Note 12). The mixture is then added rapidly to a vigorously stirred mixture of 1.0 L of ice water and 200 mL of ethyl acetate (Note 13). The organic phase is separated and the almost black aqueous phase is extracted twice with 200 mL of ethyl acetate (Note 14). The combined red organic phases are dried with sodium sulfate. The solvent is removed under reduced pressure and the crude product is dried at low pressure, whereupon 12.9 to 15.7 g (47-57%) of an orange powder, mp 186-190°C, is obtained (Note 15). The crude product is sufficiently pure for the next step. Further purification is possible by recrystallization from acetone/water. 

Formylfuran behaves in a very similar manner to benzaldehyde and undergoes the usual reactions of an aromatic aldehyde, e.g. (i) the Cannizzaro reaction with cone, sodium hydroxide to give furan-2-ylmethanol and the sodium salt of furoic acid, (ii) the Perkin reaction with acetic anhydride and sodium acetate to yield an aldol product that dehydrates to 3-(furan-2-yl)propenoic acid, and (iii) a condensation with potassium cyanide in alcoholic solution to form furoin (under these conditions, benzaldehyde undergoes the benzoin condensation) (Scheme 6.32). 

The sal natron liquor, prepared by heating crude nitrate from the aqua vicja tanks with 15 per cent, of coal dust, is made into a cone 5 ft. high with a kind of moat dug round the base of the cone. The cone is sat. with water and ignited. The crude sodium carbonate formed fuses and runs into the pit. The product dissolved in water forms the sal natron liquor. The sodium bisulphate soln. is made by passing the fumes of burning sulphur into the sal natron liquor. The liquid acid is then acid enough to liberate iodic acid from iodates. 

To summarize the production of sodium hypochlorite is favoured by (i) Neutral cone. soln. of sodium chloride (ii) Low temp. (iii) High anodic current density (iv) The presence of potassium bichromate and (v) An adequate circulation of the electrolyte. G. E. Cullen and R. S. Hubbard have studied the best... 

M. Couleru recommends the use of a cone. soln. of sodium chromate for the successful production of perchlorates. The action is similar to that which is obtained by a little chromate in the electrolyte during the production of chlorates. The sodium perchlorate so produced is very soluble and deliquescent, and it is not usually worked up, but rather converted into the ammonium or potassium salt by the addition of ammonium or potassium chloride. It is advisable to ensure that all the chlorate has been converted into perchlorate before precipitating the perchlorate, otherwise the perchlorate will be contaminated by the chlorate in solid soln. which cannot be removed by washing. A. Angeli recommends electrolyzing... 

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