Fall-2013- Chemistry 2311 Homework Problems- Chapter 4 (1) Provide the IUPAC name for each of the following molecules. (a) (b) (c) (d)(e) (f) (g) (h) (i)(j) (k) (2) Draw a bond-line structure for each of the following. (a) Allylcycloheptane (b) 4-methoxy-1-hexyne(c) trans-1,4-Dichloro-2-butene (d) cis-3-tert-Butylcyclohexanol (e) Vinylcyclopropane (f) 1-Neopentylcyclobutane (g) Bicyclo [2.2.2]octene(3) Sketch a “potential energy” vs. “rotation” curve showing in general terms the energy changes arising from rotation about the C2-C3 bond of 2-methylbutane. The actual numerical energy values are not important. Draw the conformational structures for all maxima and minima. Potential EnergyRotation0o60o120o180o240o300o360o (4) Draw all the chair conformations of trans-1,3-dichlorocyclohexane. Circle the most stable conformation.(5) Complete each of the following reactions: (a) (b) (6) The infrared spectrum of a molecule whose formula is C6H12O is given below. Draw a structure consistent with this spectrum.(7) Which of the following structures is consistent with the following infra red spectrum? OCOH OO OO OHO(8) Indicate True (T) or False (F) for each of the following statements: (a) The temporary molecular shape that results from rotation of groups about single bonds is called a conformation of a molecule. (b) The eclipsed conformation of ethane is more stable than the staggered conformation. (c) The phenomenon of electron delocalization (via orbital overlap) from a filled bonding orbital to an adjacent unfilled orbital is called hyperconjugation. (d) The barrier to rotation about a single bond is called the torsional barrier of that particular single bond. (e) The factors involved in the rotational barrier about a carbon-carbon single bond are together called torsional strain. (f) Considering the rotation about the C2-C3 bond of butane, the gauche conformation is more stable than the anti conformation. (g) The heat of formation of a hydrocarbon is the enthalpy (ΔH) change for the complete oxidation of the hydrocarbon to carbon dioxide and water. (h) Cyclobutane has a greater stain energy compared to cyclohexane. (i) The C-C-C bond angles in cyclohexane are approximately 109.5o. (j) The diaxial conformation of cis-1,3-dimethylcyclohexane is more stable than the diequatorial conformer. (k) The cis-isomer of 1,2-dimethylcyclohexane has one methyl group axial and the other methyl group equatorial. (l) cis-2-Butene has an index of hydrogen deficiency equal to one while the corresponding trans-isomer has an index of hydrogen deficiency equal to two. (m) Cyclohexane is produced from cyclohexene by the addition of hydrogen in the presence of a transition metal catalyst such as platinum, palladium, or nickel. (n) The twist boat conformation of cyclohexane is more stable than the chair form of cyclohexane. (o) The carbon atoms in cyclobutane lie in a plane.(p) The heat of combustion of isobutene is -2868 kJ/mol and the heat of combustion of butane is -2877 kJ/mol. This indicates that butane is more stable than isobutene. (q) The index of hydrogen deficiency of allyl alcohol is
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