Sodium tert-butanol

Sodium/tert-butanol Syntheses with iodonium salts... 

Sodium tert-butanol a,y - thyleneoximes and zl -isoxazolines from 1,3-aminooximes... 

Because trimethylsilanol 4 is more acidic than methanol or tert-butanol, tri-methylsilanol 4 and hexamethyldisiloxane 7 react rapidly with 12 M NaOH, KOH, or LiOH to give colorless crystalline precipitates of sodium trimethylsilanolate 96... 

A Lewis acid is also necessary for the acetylation of tetracarbonylferrate using N-acetylimidazole. In the absence of a Lewis acid, a Claisen-type condensation product was formed, which has been synthesized independently from 2 moles of A-acetylimidazole with sodium terf-butanolate in tert-butyl alcohol (55% yield) or with imidazole sodium in THF (95% yield) ... 

For the conversion of (15)-(+)-3-carene approximately 0.045 mg mL ( 1.2 /tm) CPO was incubated in 100 mM citric acid buffer, pH 3.5 with 25 % (v/v) tert-butanol containing 10 him (15)-(+)-3-carene (final assay concentration) and 10 him sodium chloride, sodium bromide or sodium iodide (final assay concentrations) in a 50 mL vessel on a magnetic stirrer (300 rpm) at room temperature. Hydrogen peroxide was added to a total concentration of 10 ruM over a reaction time of 60 min at a rate of 165 /iM min (165 portions every minute). 

The nickel oxide electrode is generally useful for the oxidation of alkanols in a basic electrolyte (Tables 8.3 and 8.4). Reactions are generally carrried out in an undivided cell at constant current and with a stainless steel cathode. Water-soluble primary alcohols give the carboxylic acid in good yields. Water insoluble alcohols are oxidised to the carboxylic acid as an emulsion. Short chain primary alcohols are effectively oxidised at room temperature whereas around 70 is required for the oxidation of long chain or branched chain primary alcohols. The oxidation of secondary alcohols to ketones is carried out in 50 % tert-butanol as solvent [59], y-Lactones, such as 10, can be oxidised to the ketoacid in aqueous sodium hydroxide [59]. 

Esterification of linalool requires special reaction conditions since it tends to undergo dehydration and cyclization because it is an unsaturated tertiary alcohol. These reactions can be avoided as follows esterification with ketene in the presence of an acidic esterification catalyst below 30 °C results in formation of linalyl acetate without any byproducts [71]. Esterification can be achieved in good yield, with boiling acetic anhydride, whereby the acetic acid is distilled off as it is formed a large excess of acetic anhydride must be maintained by continuous addition of anhydride to the still vessel [34]. Highly pure linalyl acetate can be obtained by transesterification of tert-butyl acetate with linalool in the presence of sodium methylate and by continuous removal of the tert-butanol formed in the process [72]. 

Styrene is difficult to purify and keep pure. Usually contains added inhibitors (such as a trace of hydroquinone). Washed with aqueous NaOH to remove inhibitors (e.g. tert-butanol), then with water, dried for several hours with MgSO4 and distd at 25° under reduced pressure in the presence of an inhibitor (such as 0.005% p-rert-butylcatechol). It can be stored at -78°. It can also be stored and kept anhydrous with Linde type 5A molecular sieves, CaH2, CaSO4, BaO or sodium, being fractionally distd, and distd in a vacuum line just before use. Alternatively styrene (and its deuterated derivative) were passed through a neutral alumina column before use [Woon et al. JACS 108 7990 1986 Collman JACS 108 2588 7986]. 

Although many recent improvements in the preparation of the Simmons Smith reagent might be helpful23 24, the authors of this chapter would recommend one to consider an alternative two-step cyclopropanation procedure, which includes cycloaddition of dichloro- or dibromocarbene to methylenecycloalkane25 followed by reductive dehalo-genation (equation l)26. The first reaction is usually carried under phase transfer conditions and presents a very simple and efficient procedure. Reduction of gem-dihalocyclopropanes with lithium in tert-butanol or with sodium in liquid ammonia usually proceeds without complications and with high yield. 

The ketone is added to a large excess of a strong base at low temperature, usually LDA in THF at -78 °C. The more acidic and less sterically hindered proton is removed in a kineti-cally controlled reaction. The equilibrium with a thermodynamically more stable enolate (generally the one which is more stabilized by substituents) is only reached very slowly (H.O. House, 1977), and the kinetic enolates may be trapped and isolated as silyl enol ethers (J.K. Rasmussen, 1977 H.O. House, 1969). If, on the other hand, a weak acid is added to the solution, e.g. an excess of the non-ionized ketone or a non-nucleophilic alcohol such as tert-butanol, then the tautomeric enolate is preferentially formed (stabilized mostly by hyperconjugation effects). The rate of approach to equilibrium is particularly slow with lithium as the counterion and much faster with potassium or sodium. 

Potassium—sodium alloy See Potassium—sodium alloy tert-Butanol... 

The successful extension of this asymmetric reaction to the use of allyl halides (instead of benzyl halides) was also reported by the Metzner group [208]. The desired vinyl oxiranes were formed in a one-pot reaction starting from an allyl halide and an aromatic aldehyde in the presence of a sulfide, e.g. 215, and sodium hydroxide as base. A 9 1 mixture of tert-butanol and water was used as solvent. 

A mixture of 23.9 g ethyl 2-carboxy-3-nitrobenzoate and 12 ml thionyl chloride in 150 ml benzene were heated under reflux for 3 hours. The reaction mixture was concentrated to dryness. The resultant acid chloride (26 g) was dissolved in 20 ml. The solution was added to a mixture of sodium azide (9.75 g) in 20 ml DMF with stirring. The reaction mixture was poured into 200 ml a mixture of ether-hexane (3 1). The organic layer was washed with water and evaporated. The residue was dissolved in 200 ml tert-butanol and the solution was heated gradually with stirring, followed by heating under reflux for 2 hours. The reaction mixture was concentrated to give an oily ethyl 2-butoxycarbonylamino-3-nitrobenzoate (30 g). 

To a mixture of 50 g 2-[4-[(4-chlorophenyl)phenylmethyl]-l-piperazinyl]-ethanol and 225 ml of tert-butanol at 45°C under a nitrogen was added 21 g tert-BuOK. The temperature was raised to 75-80°C and the mixture was kept at this temperature. After 45 min was added 11 g sodium chloracetate after 1.5 hour was added 5.2 g tert-BuOK after 2 hours was added 5.64 g sodium chloracetate after 2.5 hours was added 1.9 g tert-BuOK after 3 hours was added 1.9 g sodium chloracetate after 3.5 hours was added 0.8 g tert-BuOK and after 4 hours was added 1.13 g sodium chloracetate. Then about 150 ml tert-butanol was distilled of, 190 ml of water was added and the distillation of tert-butanol was continued until the temperature of the vapour reaches 100°C. To the reaction mixture was added 60 ml of water and 8 ml concentrated hydrochloric acid to pH 8. Unreacted 2-[4-[(4-chlorophenyl) phenylmethyl]-l-piperazinyl]-ethanol was extracted with diethyl ether. The aqueous phase was acidified to pH 5 by addition of hydrochloric acid and extracted with dichloromethane (200 ml x 3). The extract was dried over MgS04, filtered and concentrated in a rotary evaporator. An obtained oil was allowed to crystallize by addition of 150 ml of 2-butanone, yields of 2-[4-[(4-chlorophenyl)phenylmethyl]-l-piperazinyl]-ethoxy]acetic acid 55.5%, M.P. 146-148°C. 

Note Triethylamine proved to be a better base in this particular synthesis than sodium acetate, sodium carbonate, sodium hydride or potassium tert-butanolate. 

Birch reduction of aromatic compounds involves reaction with an electron-rich solution of alkali metal lithium or sodium in liquid ammonia (sometimes called metal ammonia reduction). Usually a proton donor such as tert-butanol or ethanol is used to avoid the formation of excess amount of LiNH2 or NaNH2. The major product is normally a 1,4-diene. This reaction is related to the reduction of alkynes to frans-alkenes ° (section 6.2.2). 

Cyclopentenediol isomers have previously been prepared by hydrolysis of acetates produced by reaction of dibromocyclopen-tene with potassium acetate in acetic acid 2 by reaction of cyclo-pentene with selenium dioxide in acetic anhydride or by reaction of cyclopentadiene with phenyl iodosoacetate,4 with lead tetraacetate,6 or with peracetic acid in the absence of base. Preparation of cyclopentenediol without intermediate formation of acetates has been accomplished by reaction of cyclopentadiene with hydrogen peroxide in the presence of osmium tetroxide in tert-butanol,7 and by reaction of cyclopentadiene with peracetic acid in a methylene chloride suspension of anhydrous sodium carbonate, followed by hydrolysis of the resulting epoxycyclopen tene.8... 

Asymmetric dihydroxylation of the side-chain of Z-1-(4-meth-oxyphenyl)-1-(tert-butyldimethylsiloxy)-1-propene to give (R)-l-hydroxyethyl 4-methoxyphenyl ketone in 94% yield (99% e.e.) was effected by addition of the alkene to a stirred mixture of osmium tetroxide, potassium ferricyanide, potassium carbonate, a 9-0-(9 -phenanthryl)ether(PHN) of dihydroquinidine and 1 mole of methanesulphonamide in aqueous tert-butanol (1 1), with reaction during 16 hours at ambient temperature. Then treatment with sodium sulphite prior to work-up to gave the product (ref. 130). Other best ligands were the 9-0-(4 -methyl-2 -quinolyl) ethers (MEQ) of dihydroquinine. 

The vinylogous amide lactam 411 prepared by the route described previously (203) was N-tosylated in 44% yield by reaction with sodium hydride in boiling monoglyme followed by treatment with tosyl chloride. On treating the tosyl derivative 428 with excess acrylonitrile in tert-butanol-dimethyl sulfoxide in the presence of potassium re/t-butoxide, two products were formed the pentacylic derivative 429 and the hexacyclic compound 430. Further base treatment of the former compound gave 430 in quantitative yield, thereby bringing the overall reaction yield to a respectable 50%. 

Although DBN and DBU are very selective, the most common bases used in E2 reactions are hydroxide (in water) or alkoxides in alcohol solvent (sodium methoxide in methanol, sodium ethoxide in ethanol, potassium tert-butoxide in tert-butanol). Amide bases such as sodium amide or lithium diethylamide can be used in ammonia or amine solvents. In these latter cases, the bases are also good nucleophiles and in reactions with... 

In most cases, an aqueous solution of the quinone has been used for radiation chemical studies. However, the reaction sequence depends entirely on the added scavengers like sodium formate, methanol, 2-propanol, tert-butanol or others. In om own work, we have extensively used a relatively novel solvent system comprising of a mixture of 2-propanol (5 mol dm ) and acetone (1 mol dm ) in water (32.5 mol dm ). The advantage of this system, over and above solubilizing quinones insoluble in water, lies in the chemistry involved [26,27], so that (CH3)2C 0H radical is produced as an exclusive reducing agent. 

To a three-necked flask equipped with a mechanical stirrer, thermometer, gas inlet, and gas outlet device is added 112gm (1.5 mole) of tert-butanol. Then 0.5 gm (0.45 wt%) of tropylium fluoroborate is added and the temperature rises to 75-83°C. Then 132 gm (3.0 mole) of ethylene oxide is added over a 1-hr reaction time. The final product is obtained by neutralizing with sodium hydroxide, filtering the salts, and stripping the resulting liquid under reduced pressure. The unreacted alcohol amounted to only 10%. 

---