Interpretation: The percentage compositions of the mixture of isomeric methylbutenes obtained from 2-bromo-2-methylbutane with potassium hydroxide and potassium tert-butoxide needs to be calculated.
Concept Introduction: In the dehydrogenation reaction of 2-bromo-2-methyl butane, mixture of products is formed only if the halogen is asymmetrically located on the carbon skeleton.
2-bromo-2-methyl butane results in the production of 2-methyl-2-butene and 2-methyl-1-butene on reaction with a strong base that is KOH. The elimination reaction is irreversible thus, the ratio of products formed are defined by the relative rates of the formation of two products.
The rate of the formation is determined by the relative free energies of the 2-transition states rather than the free energies of the products itself.
The product formed in higher yield is more substituted
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Experimental Organic Chemistry: A Miniscale & Microscale Approach (Cengage Learning Laboratory Series for Organic Chemistry)
- P12D.8 Sketch the EPR spectra of the di-tert-butyl nitroxide radical (4) at 292 K in the limits of very low concentration (at which the averaging effect of electron exchange is negligible), moderate concentration (at which electron exchange effects begin to be observed), and high concentration (at which electron exchange effects predominate). 4 di-tert-butyl nitroxidearrow_forwardCalculate the relative population differences (Nɑ - Nβ)/N for 13C nuclei in fields of (i) 0.50 T, (ii) 2.5 T, and (iii) 15.5 T at 25 °C.arrow_forwardA 400 MHz 'H NMR spectrum of a mixture of common organic solvents consisting of benzene (CHs) 8 7.37; diethyl ether (C4H100) 8 3.49 and 8 1.22; and dichloromethane (CH;Cl2) 8 5.30 is given below. Estimate the relative proportions (mole %) of the 3 components from the integrals in the spectrum. CH3-CH2-0-CH2-CH3 Cl-CH2-CI benzene diethyl ether dichloromethane 'H NMR Spectrum (400 MHz, CDCl, solution) 3.5 3.4 ppm 1.3 12 ppm 8 ppm Compound Mole % benzene diethyl ether dichloromethanearrow_forward
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- Principles of Instrumental AnalysisChemistryISBN:9781305577213Author:Douglas A. Skoog, F. James Holler, Stanley R. CrouchPublisher:Cengage Learning