Sodium bi-carbonate

Tabie 4 Rate Constants of Radiation-Induced Reactions in Sodium (Bi)carbonate Aqueous Solution... 

Magnesium Citrate.—This salt is used in medicine as a purgative. Mixed with sodium bi-carbonate, free citric acid and sugar it produces a pleasant ejffervescing purgative. 

Water insolubles Sodium bi-carbonate Iron as Fe Copper as Cu Arsenic as As... 

Oxidation in solution To a solution of thiol (1 1 mmol) in dichloromethane (10 itiL) was added DBDMH (1 mmol), and the mixture was stirred vigorously at room temperature for stipulated time (monitored by TLC). After completion of the reaction, 20 itiL of dichloromethane was added and the reaction mixture was extracted with saturated sodium bi-carbonate (2 x 20 mL) and dried over anhydrous calcium chloride (1 g). Evaporation of the solvent, followed by recrystallization or chromatography on silica gel, afforded pure disulfide 2 in 87-94% yield. 

If alkyl groups are attached to the ylide carbon atom, cis-olefins are formed at low temperatures with stereoselectivity up to 98Vo. Sodium bis(trimethylsilyl)amide is a recommended base for this purpose. Electron withdrawing groups at the ylide carbon atom give rise to trans-stereoselectivity. If the carbon atom is connected with a polyene, mixtures of cis- and rrans-alkenes are formed. The trans-olefin is also stereoseiectively produced when phosphonate diester a-carbanions are used, because the elimination of a phosphate ester anion is slow (W.S. Wadsworth, 1977). 

The systematic name for bi carbonate ion is hydrogen carbonate Thus the system atic name for sodium bicar bonate (NaHCOs) is sodium hydrogen carbonate... 

The synthesis of key intermediate 6 begins with the asymmetric synthesis of the lactol subunit, intermediate 8 (see Scheme 3). Alkylation of the sodium enolate derived from carboximide 21 with allyl iodide furnishes intermediate 26 as a crystalline solid in 82 % yield and in >99 % diastereomeric purity after recrystallization. Guided by transition state allylic strain conformational control elements5d (see Scheme 4), the action of sodium bis(trimethylsilyl)amide on 21 affords chelated (Z)-enolate 25. Chelation of the type illustrated in 25 prevents rotation about the nitrogen-carbon bond and renders... 

A solution of ( )-l,2-bis(trimethylsilyl)oct-l-ene (12mmol) in glacial AcOH (31 ml) and H20 (1.6 ml) was heated with stirring at 110°C for 29 h. The mixture was then cooled to0°C, aqueous NaOH (60 ml, 9 m) added, and the total was extracted with ether (50 ml). The ethereal extract was washed with saturated sodium hydrogen carbonate solution and brine, and dried. Concentration and distillation gave 2-trimethylsilyloct-l-ene (U.5mmol, 96%), b.p. 106 °C/1 mmHg. 

Sodium hydrogen acetate (diacetate) Sodium hydrogen carbonate Sodium hydrogen (bi) sulphite... 

Since sodium borohydride usually does not reduce the nitrile function it may be used for selective reductions of conjugated double bonds in oc,/l-un-saturated nitriles in fair to good yields [7069,1070]. In addition some special reagents were found effective for reducing carbon-carbon double bonds preferentially copper hydride prepared from cuprous bromide and sodium bis(2-methoxyethoxy)aluminum hydride [7766], magnesium in methanol [7767], zinc and zinc chloride in ethanol or isopropyl alcohol [7765], and triethylam-monium formate in dimethyl formamide [317]. Lithium aluminum hydride reduced 1-cyanocyclohexene at —15° to cyclohexanecarboxaldehyde and under normal conditions to aminomethylcyclohexane, both in 60% yields [777]. 

Bis[3-phcnyl-l-rf-propyl] Ditellurium1 A suspension of 266 mg (2.0 mmol) 3-phenylpropanal and 1.75 g (4.0 mmol) aluminum telluridein 10 ml tetrahydrofuran is cooled to - 78°. A solution of 0.21 m/(4.0 mmol) of concentrated (98%) sulfuric acid in 1.75 ml (96 mmol) deuterium oxide is added to the chilled suspension. The mixture is wanned to 20° and then heated to the reflux temperature with continuous stirring over a 30 min period. The mixture is then refluxed for 1.5 h. After cooling to 20°, the black precipitate is removed by filtration. The filtrate is washed with aqueous sodium hydrogen carbonate solution and dried with calcium sulfate. The mixture is filtered, the solvent removed from the filtrate, and the residue chromatographed with hexane/benzcnc (1 1) as the mobile phase. The product was obtained as a dark-red oil in 70% yield. 

Bis[2-carboxyphenvl] Ditellurium [Sodium disulfite Method]3 10 g (0.03 mol) of 2-carboxyphenyl tellurium bromide are suspended in 100 ml of water and a 10% solution of sodium disulfitc is added dropwiseto the red suspension. The precipitate is collected, dissolved in sodium hydrogen carbonate solution, filtered, and acid is added to the filtrate. The precipitated product is filtered yield 4.1 g (52%) m.p. 216° (dec.). 

Summary Ammonium perchlorate is prepared by addi ng a concentrated ammoni a solution to a concentrated solution of sodium perchlorate, and then passing carbon dioxide into the solution over several hours to precipitate the sodium as the water i nsol ubl e sodi urn bi carbonate. The ammoni urn perchl orate remai ns i n sol uti on, and the sol uti on i s then fi Itered. Thereafter, the ammonium perchlorateisthen collected by recrystallization. 

An older nomenclature system, still in use to some extent, uses the word acid to denote an acid salt. Also, the prefix bi- may be used for an acid salt of an acid with two ionizable hydrogen atoms. Thus, NaHCOs can be called sodium bicarbonate or sodium acid carbonate instead of sodium hydrogen carbonate (Figure 6.5). 

In an older nomenclature system, the word acid was used to denote an acid salt. In another old system, the prefix bi- was used for a half-neutralized acid that originally contained two ionizable hydrogen atoms. Thns, sodium bicarbonate and sodium acid carbonate are other names that have been nsed for NaHC03. 

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