Sodium butoxide, solution

A sodium butoxide solution is prepared in a flask attached to a reflux condenser by heating 23.5 g. of sodium with 300 ml. of commercial redistilled butyl alcohol (b. 115.5 to 117.5°C.). The resulting solution must be sufficiently free from color so as not to mask the effect of the indicator. The sodium dissolves rather slowly unless an elevated temperature is maintained. The brown color which is imparted to the warm alkaline solution as it is poured rapidly from the flask to the dropping funnel is not troublesome. 

NSodium Butoxide Transfer 9.62 g of sodium butoxide solution (50% in butanol) into a 100-mL volumetric flask, dilute to volume with 1-butanol, and mix. 

Heating 3,4-bis(phenylsulfonyl)furoxan with a solution of sodium butoxide in butanol followed by reduction with trimethyl phosphite gives furazan 281 (Scheme 183). Compound 281 was converted into dialkoxy derivative 282 with the lithium salt of ( )-l-azabicyclo[2.2.2]octan-3-ol in 33% overall yield (96W012711, 97EUP773021, 98JMC379). 

A 250-ml three-necked flask is fitted with a condenser (drying tube). The system is flushed with dry nitrogen, and a dry nitrogen atmosphere is maintained. In the flask is placed a solution of potassium /-butoxide (2.8 g, 0.025 mole) in dry /-butyl alcohol (100 ml). 4-Benzoyloxycyclohexanone (5 g, 0.022 mole, Chapter 7, Section X) is added to the solution, the transfer being assisted by the use of 10-15 ml of dry /-butyl alcohol. The mixture is cautiously brought to reflux, and refluxing is continued for 45 minutes. The mixture is then cooled rapidly to room temperature and carefully acidified by the addition of 10 ml of 6 A hydrochloric acid (potassium chloride will precipitate). The mixture is placed on a rotary evaporator and the bulk of the solvent is removed. The residue is diluted with sufficient water to dissolve the potassium chloride and extracted three times with 50-ml portions of ether. The ether extracts are combined and extracted four times with 100-ml portions of aqueous 5% sodium bicarbonate solution. The bicarbonate extracts are combined and the solution is acidified by the addition of concentrated hydrochloric acid to pH 4. The mixture is now extracted three times with 100-ml portions of ether, the combined ethereal extracts are washed with water, then dried, and the solvent is removed. The residual product may be recrystallized from benzene-hexane. The acid has mp 65-68°. 

Silicon, higher chlorides of, 42 Silicon tetrabromide, 38, 40 Silicon tetrachloride, 44 Silicopropane, octachloro, 44 Silicotungstic acid, 129 analysis, 131 ether complex, 131 Silver, metallic, 4 Silver chloride, reduction of, 3 Silver cyanamide, 98 Silver residues, purification of, 2 Sodium amalgam, 10 Sodium amide, 74 Sodium azide, purification of, 79 Sodium azidodithiocarbonate, 82 Sodium butoxide, 88 Sodium hypochlorite (solution), 90 Sodium iodate, 168 Sodium metaperiodate, 170 Sodium paraperiodate, chlorine method, 169 persulfate method, 170 Strontium amalgam, 11 Sulfur hexafluoride, 121 Sulfuryl chloride, 114... 

Dimethyl malonate (4.04 g, 30.6 mmol), potassium t-butoxide (3.43 g, 30.6 mmol) and anhydrous N,N-dimethylformamide (15 ml) were mixed and stirred for 10 minutes in a nitrogen atmosphere at 90°C. The mixture was then cooled to room temperature, and to the cooled mixture was added a solution of diethyl 2-(3-chloro-4-nitrophenyl)-2-methylmalonate (5.04 g, 15.3 mmol) prepared in the manner as described in Japanese Patent Publication No. 47-45, 746) in anhydrous N,N-dimethylformamide (15 ml). The resulting mixture was stirred at 90°C for 3 hours, and then poured into 1 N hydrochloric acid (30 ml). The mixture was subjected to extraction using two portions of diethyl ether. The ether extracts were combined, washed successively with water and an aqueous saturated sodium chloride solution, and dried over anhydrous sodium sulfate. The dried extract was placed under reduced pressure to give 7.97 g of yellow oil. The oil was adsorbed on silica gel (16 g) and subjected to... 

Sodium amide, 1 74, 2 80, 128, 134 Sodium amidophosphate (Na2P03NH2), 6 100 anhydrous, for preparation of tetrasodium imidodiphos-phate, 6 101 Sodium azide, 2 139 purification of, 1 79 Sodium azidodithiocarbonate, solution of, 1 82 Sodium butoxide, 1 88 Sodium carbonate, Na2C03, light, for preparation of chlorine (I) oxide, 5 159... 

Condensation of hydrazine with formaldehyde (37% solution) and hydrogen sulfide in water in the presence of a sodium butoxide-butanol buffer (pH 10.75-11.5) gives a mixture of products. The reactant ratio is an important factor in determining the product ratio and, when a 6 4 1 ratio of HCHO-H2S-H2NNH2 was used, the perhydro-A-(l,3-thiazet-3-yl)-l,3,5-dithiazine 48 was isolated in 5-6% yield in addition to other S,N-heterocycles (Equation 18) <2006RJ0145>. 

Procedure For each sample (hexane blank, Standard Reference Solution, and Sample Solution) to be assayed, pipet 5.0 mL of solution into a clean 8-mL clear glass vial. Add 0.5 mL of 0.5 N sodium butoxide, seal, and shake vigorously. The solution will turn yellow. For the hexane blank and the Sample Solutions only, allow the solution to stand for 2 min. Neutralize the mixture by adding 1.0 mL of 0.5 N hydrochloric acid. Seal the vial, and shake well until the solution is clear. Check the pH with pH paper. The solution should be acidic. If it is not, the column will degrade. 

N sodium butoxide and 0.5 N hydrochloric acid, respectively, for the Standard Reference Solution. 

Although potassium fert-butoxide (f-BuOK), sodium methylate (NaOCHs), sodium ethylate (NaOC2H5), alcoholic potassium hydroxide, and sodium hydroxide solutions have been used, the utilization of the... 

The phenol (Imol) in 5% aqueous NaOH is treated (while cooling) with benzoyl chloride (Imol) and the mixture is stirred in an ice bath until separation of the solid benzoyl derivative is complete. The derivative is filtered off, washed with alkali, then water, and dried (in a vacuum desiccator over NaOH). It is recrystallised from ethanol or dilute aqueous ethanol. The benzoylation can also be carried out in dry pyridine at low temperature (ca 0°) instead of in NaOH solution, finally pouring the mixture into water and collecting the solid as above. The ester is hydrolysed by refluxing in an alcohol (for example, ethanol, n-butanol) containing two or three equivalents of the alkoxide of the corresponding alcohol (for example, sodium ethoxide or sodium -butoxide) and a few (ca 5-10) millilitres of water, for half an hour to three hours. When hydrolysis is complete, an aliquot will remain clear on dilution with four to five times its volume of water. Most of the solvent is distilled off. The residue is diluted with cold water and acidified, and the phenol is steam distilled. The latter is collected from the distillate, dried and either fractionally distilled or recrystaUised. It can also be isolated by extraction from a slightly acidified (pH 3) aqueous solution with diethyl ether. 

In case of carboxylic acid starting materials, they were first converted into their corresponding acyl chlorides by reacting with oxalyl chloride in dichloromethane. A cooled dichloro-methane solution of an acyl chloride (1 1 mmol) in a 25 mL round bottomed flask was then added with triethylphosphite (1 mmol) drop-wise under stirring, and the reaction mixture was allowed to attain room temperature. On completion of the formation of acyl phosphonate, the reaction mixture was reduced in vacuo, and benzoic acid (2 mmol) was added directly to the residue, followed by benzene. The mixture was stirred to dissolve completely, then hydrazine solution in THF (1.05 mmol) was added drop-wise under rapid stirring. On completion of hydrazone formation, the reaction was flash-frozen and lyophilized. After lyophilization, 1 1 v/v tetrahydrofuran ferf-butanol was added to the flask and stirred to dissolve the solid. Potassium ferf-butoxide solution (3 mmol) in 1 1 v/v tetrahydrofuran ferf-butanol was then added to the stirring solution in one portion. After stirring at room temperature for several hours, the reaction was diluted with ethyl acetate (50 mL), quenched with 1 N HCl (20 mL), washed with saturated sodium bicarbonate (2 x 15 mL), then with brine (15 mL),... 

Di4ert-butoxypyrimidine (2). Uracil (1) was reacted with phosphorus asy-chloride to give 2,4-dichloropyrimidine (4) (9). Potassium (0.78 g, 20 mmol) was added to potassium tert-butoxide solution. To the solution, 2,4-dichloropyrimidine (13 g, 10 mmoO was added at room temperature, and the mbdure was stirred under reflux for 1 hour. After the reaction, the precipitated KG was removed filtration, and the solvent was removed by evaporation. The residue was dissolved in diethyl ether, and washed with 30% aqueous KOH and dried over sodium sulfate. After evaporation of the solvent, the product was obtained by distillation under reduced pressure. Yield 1.1 g (49%). IR 1580 and 1155 on H-NMR (CDGj, TMS, 8) 1.4 (18H, s), 6.0 (IH, d), and 7.9 (IH, d). 

Pentacarbonyliron (2.9 g, 15 mmol) is added dropwise to a solution of anhydrous potassium butoxide (1.68 g, 15 mmol) in tetrahydrofuran (70 mL) at 25 C under dry nitrogen. The color of the reaction mixture immediately changes from yellow to dark brown. The reaction mixture is stirred for another 1 h at 70 °C and brought slowly to 25 °C. Diphenylacetylene (0.44 g, 2.5 mmol) is added and further stirred for 10 h at 70 C. The mixture is brought slowly to 25 °C. The metal carbonyl complexes are oxidized using copper(II) chloride dihydrate (5.0 g, 30 mmol) in acetone (20 mL). Saturated sodium chloride solution is added and the contents are extracted with ether (2 x 75 mL), dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue is subjected to column chromatography [silica gel, hexane (2%)/ethyl acetate] to afford the pure 3,4-diphenyl-3-cyclobutene-1,2-dione mp 95-96 °C, 0.52 g (88%) ... 

Reinhoudt, Gray, Smit and Veenstra prepared a number of monomer and dimer crowns based on a variety of substituted xylylene units. They first conducted the reaction of 1,2-dibromomethylbenzene and a polyethylene glycol with sodium hydride or potassium Z-butoxide in toluene solution. Mixtures of the 1 1 and 2 2 (monomer and dimer) products were isolated and some polymer was formed . The reaction was conducted at temperatures from 30—60° and appeared to be complete in a maximum of one hour. The authors noted that the highest yield of 1 1 cyclic product was obtained with disodium tetraethylene glycolate instead of dipotassium hexaethylene gly-colate (see also Chap. 2) . Chloromethylation of 1,3-benzodioxole followed by reaction with disodium tetraethylene glycolate afforded the macrocycle (29% yield) illustrated in Eq. (3.20). 

Timko and Cram were the first to prepare true crown ethers containing the furanyl subcyclic unit ° . Destructive distillation of sucrose yielded 2-hydroxymethyl-5-formyl-furan 7 in 41% yield. This could be reduced to the corresponding diol in 91% yield by treatment with sodium borohydride. Reaction of the diol with tetraethylene glycol dito-sylate, and potassium t-butoxide in THE solution afforded the crown in 36% yield. The approach is illustrated below as Eq. (3.26). 

In a dry, 250 ml, three-necked flask equipped with a dropping funnel and magnetic stirrer are placed 40 ml of dry /-butyl alcohol (distilled from calcium hydride) and 4.0 g (0.036 mole) of potassium /-butoxide. The solution is cooled in ice and 40 g (49 ml, 0.49 mole) of dry cyclohexene is added. Bromoform (10 g, 3.5 ml, 0.039 mole) is added to the cooled, stirred reaction vessel dropwise over about hour, and the vessel is stirred an additional hour with the ice bath removed. The reaction mixture is poured into water (approx. 150 ml), and the layers are separated. The aqueous layer is extracted with 25 mi of pentane, and the extract is combined with the organic layer. The combined layers are dried (sodium sulfate), and the solvent is removed. The product is purified by distillation, bp 10078 mm. 

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