Isopropyl alcohol elimination

Substances whose poisonous metabolites are eliminated slowly Ethylene glycol, methanol, primidone, isopropyl alcohol, carbon tetrachloride, levothyroxine. 

Another synthetic use of the M-P-V reaction has been exploited in the synthesis of new alkoxide derivatives.247,248 Hence, 2-hydroxybenzaldehyde (salicylaldehyde) will react with isoproxides of titanium and zirconium to initially displace isopropyl alcohol and give mixed derivatives which on heating undergo reduction of the aldehyde function with elimination of acetone. The stoichiometry of the overall reaction can be represented as shown in equation (66).248... 

The uncatalyzed H02 elimination from the peroxyl radical derived from methanol is too slow to be measured at room temperature (k < 10 s-1). That derived from ethanol eliminates H02" with k = 52 s and that derived from isopropyl alcohol undergoes an even faster elimination of HOj (k = 665 s-1). The activation energies are,T —60 kj. mol-1. If OH - acts as the base, reaction 38 occurs at rates that are near to diffusion-controlled. The catalysis by phosphate is three orders of magnitude slower. 

The reaction of sodium methoxide with isopropyl bromide will proceed mainly by elimination. Methyl bromide is prepared as shown previously sodium isopropoxide can be prepared by adding sodium to isopropyl alcohol. 

Air dry, or dry with heat if available. For more rapid drying, bathe in isopropyl alcohol or a good denatured alcohol for 1 to 2 minutes. The film should then be dried without heat or opalescence will occur. Use of an 85% alcohol solution will eliminate opalescence, but drying will be slower. 

Elimination of bromine and ethoxyl groups with zinc is much the same as the elimination of two adjacent halogen atoms. The /6-bromo ether is heated with a stirred suspension of powdered zinc or zinc-copper couple in 90-95% ethanol, n-propyl alcohol, or isopropyl alcohol. The preparation of 3 Octene fails in n-propyl alcohol. In several cases the products have been shown to be mixtures of cis and trans isomers. The yields for the first two steps of the synthesis are 70-90%. The coupling of the a,/S-dibromo ethers with primary Grignard reagents takes place in 50-80% yields, whereas with secondary Grignard reagents only 30-55% yields are obtained. 

Isopropyl alcohol under UV irradiation converts bromobenzene to benzene in 72% yield (Table 4). Similar replacement of bromine by hydrogen is accomplished by treatment of aryl bromides dissolved in dichloromethane with a mixture of ethanethiol and anhydrous aluminum chloride. This hard acid-soft base combination reacts with polycyclic aromatic halides and halogenated phenols by an addition-elimination mechanism, leading to an aryl ethyl sulfide through a radical anion intermediate. This is converted by another molecule of ethanethiol to the debrominated arene and diethyl disulfide. 1-Bro-monaphthalene is thus transformed into naphthalene (equation 59), 2,4,6-tribromophenol into phenol (equation 60), and bromochlorophenols into chlorophenols in 61-91% yields. ... 

In contrast to the tertiary alcohols, primary (e.g., ethyl alcohol) and secondary alcohols e.g., isopropyl alcohol) decompose to products at temperatures above 800 °K via complex free radical chain processes . This mechanistic inversion is not surprising. Based on the magnitude of substituent effects in four-center elimination reactions, particularly the variations found in the series r-BuCI, i-PrCl, EtCl - , one would estimate that the isopropyl alcohol unimolecular elimination of water should have an activation energy about 6 kcal.mole higher than that for r-butyl alcohol. The. 4-factor can be estimated by transition state methods, and one obtains for the unimolecular decomposition... 

When j6-toluenesulphonyl azide was heated at 50-80° in isopropyl alcohol in the presence of diethyl peroxydicarbonate (20-3 azide 1 -4 peroxide), -toluenesulphonamide and acetone were obtained in 75 and 81% yields respectively " . It was thought that the 2-hydroxy-t-propyl radical (292) added to the azide to give 293 (equation 132) and that an intramolecular reduction and elimination of nitrogen occurred via a cyclic intermediate (294) to give the radical (295) and acetone. Hydrogen abstraction by (295) would then give the sulphonamide. 

Preconcentration of analytes in aqueous solution may be performed by a miscible organic phase followed by salting out. Thus, microextraction of anionic solntes snch as phenol, cresols and xylenols in industrial effluents can be carried ont with a small amonnt of isopropyl alcohol, followed by demixing of the phases with ammoninm snlfate. End analysis of the extract by GC-MS in the selected ion monitoring (SIM) mode allowed a LOD of 1 ppb for 50 mL samples . The best conditions for eliminating petrolenm prodncts from the concentrate were found for the GC determination of volatile phenols in natnral waters. Losses of volatile phenols due to preconcentration were insignificant and cansed no increase in the relative error of determination by the internal-standard method. The concentration of phenol in the atmosphere can be determined by sorption on Chromosorb 102, desorption with benzene and 0.1 M NaOH and GC nsing a capillary colnmn. LOD was abont 1 p,gm, with accuracy within 15% . 

Isopropyl cyclopropanesulfonate was obtained in low yield on reaction of cyclopropanesulfonyl chloride with isopropyl alcohol in the presence of triethylamine. The reaction apparently occurs via an elimination-addition process as indicated by the fact that the sulfonate obtained from 1-deuteriocyclopropanesulfonyl chloride was nondeuterated. ... 

C. Drugs or chemicals metabolized by alcohol dehydrogenase (eg, chloral hydrate, isopropyl alcohol) will also have impaired elimination. Fomepizole and ethanol mutually inhibit the metabolism of each other. 

The material proved easy to apply both manually and with a pneumatic dispenser. UV acrylic reworkability with isopropyl alcohol or heat was quick and easy as well. In this case, the acrylic was more expensive than epoxy or silicone, but proved more cost-effective because of its virtual elimination of flex failures. 

Nitrocellulose, polyester, acrylic and methacrylic ester copolymer, formaldehyde resin, rosin, cellulose acetate butyrate are the most frequently used polymers in nail polish formulations. Solvents were selected to suit the polymer used. These include acetone, methyl acetate, ethyl acetate, butyl acetate, methyl glycol acetate, methyl ethyl ketone, methyl isobutyl ketone, toluene, xylene, isopropyl alcohol, methyl chloroform, and naphtha. Solvents constitute a substantial Ifaction of the composition usually around 70%. Reformulation is ongoing to improve the flexibility and durability of the nail polish. Other efforts are directed to improve antifungal properties,to eliminate ketones and formaldehyde resin (ketones because of their toxicity and irritating smell and formaldehyde resins because they contribute to dermatitis), and elimination of yellowing. All efforts are di-... 

The dehydrohalogenation of vinyl halides in the s5mthesis of alk3mes shows steric preferences analogous to those of alkyl halides. The reaction of (Z)-)3-bromostyrene with hydroxide ion in isopropyl alcohol at 43°C was 2.1 X 10 faster than the reaction of the ( ) isomer. The results were interpreted in terms of differing mechanisms for the eliminations of the two compounds. As shown in equation 10.28, the (Z) isomer can undergo concerted elimination of hydrogen and bromine because they are in the proper orientation for anti-coplanar elimination. 

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