91Ó°ÊÓ

What three alkenes yield 2-methylbutane on catalytic hydrogenation?

Use Markovnikov's rule to predict the major organic product formed in the reaction of hydrogen chloride with each of the following: (a) 2-Methyl-2-butene (b) cis-2-Butene (c) 2-Methyl-1-butene Sample Solution (a) Hydrogen chloride adds to the double bond of 2-methyl-2-butene in accordance with Markovnikov's rule. The proton adds to the carbon that has one attached hydrogen, chlorine to the carbon that has none.

Addition of hydrogen chloride to 3,3-dimethyl-1-butene gives a mixture of two isomeric chlorides in approximately equal amounts. Suggest reasonable structures for these two compounds, and offer a mechanistic explanation for their formation.

Is the electrophilic addition of hydrogen chloride to 2 -methylpropene the reverse of the \(\mathrm{E} 1\) or \(\mathrm{E} 2\) elimination of tert-butyl chloride?

Does the presence or absence of a catalyst such as finely divided platinum, palladium, or nickel affect the equilibrium constant for the ethylene-ethane conversion?

Hydroboration-oxidation of \(\alpha\) -pinene, like its catalytic hydrogenation (Problem 8.3), is stereoselective. Addition takes place at the less hindered face of the double bond, and a single alcohol is produced in high yield (89\%). Suggest a reasonable structure for this alcohol.

Arrange the compounds 2-methyl-1-butene, 2-methyl-2-butene, and 3-methyl-1-butene in order of decreasing reactivity toward bromine.

Give the structure of the product formed when each of the following alkenes reacts with bromine in water: (a) 2-Methyl-1-butene (c) 3-Methyl-1-butene (b) 2-Methyl-2-butene (d) 1-Methylcyclopentene

1-Methylcyclopentene gives a single compound \(\left(\mathrm{C}_{6} \mathrm{H}_{12} \mathrm{O}_{2}\right)\) on ozonolysis. What is it?

The same reaction that gave \(2,4,4\) -trimethyl-2-pentene also yielded an isomeric alkene. This second alkene produced formaldehyde and 4,4-dimethyl-2-pentanone on ozonolysis. Identify this alkene.