Propose structures for the following: (a) A ketone, C4H8O (b) A nitrile, C5H9N (c) A

Identify the functional groups in the following substances, and convert each drawing into a molecular formula (red5O, blue5N).

Give IUPAC names for the following alkanes, and convert each drawing into a skeletal structure:

Draw a Newman projection along the C2C3 bond of the following conformation of 2-butanol.

Locate and identify the functional groups in the following molecules. (d) (e) (f) (a) CH2OH (b) (c) NHCH3 O C CH3 N H O CH3CHCOH O NH2 O Cl O

Propose structures that meet the following descriptions: (a) A ketone with five carbons (b) A four-carbon amide (c) A five-carbon ester (d) An aromatic aldehyde (e) A keto ester (f ) An amino alcohol

Propose structures for the following: (a) A ketone, C4H8O (b) A nitrile, C5H9N (c) A dialdehyde, C4H6O2 (d) A bromoalkene, C6H11Br (e) An alkane, C6H14 (f ) A cyclic saturated hydrocarbon, C6H12 (g) A diene (dialkene), C5H8 (h) A keto alkene, C5H8O

Predict the hybridization of the carbon atom in each of the following functional groups: (a) Ketone (b) Nitrile (c) Carboxylic acid

Draw the structures of the following molecules: (a) Biacetyl, C4H6O2, a substance with the aroma of butter; it contains no rings or carboncarbon multiple bonds. (b) Ethylenimine, C2H5N, a substance used in the synthesis of melamine polymers; it contains no multiple bonds. (c) Glycerol, C3H8O3, a substance isolated from fat and used in cosmetics; it has an OH group on each carbon.

Draw structures that meet the following descriptions (there are many possibilities): (a) Three isomers with the formula C8H18 (b) Two isomers with the formula C4H8O2

Draw structures of the nine isomers of C7H16

In each of the following sets, which structures represent the same compound and which represent different compounds? (a) Br CH3CHCHCH3 CH3 CH3 CH3CHCHCH3 Br CH3CHCHCH3 CH3 Br (c) CH3CH2CHCH2CHCH3 CH3 CH3CH2CHCH2CHCH2OH CH2OH HOCH2CHCH2CHCH3 CH2CH3 CH3 CH3 CH3

There are seven constitutional isomers with the formula C4H10O. Draw as many as you can

Draw as many compounds as you can that fit the following descriptions: (a) Alcohols with formula C4H10O (b) Amines with formula C5H13N (c) Ketones with formula C5H10O (d) Aldehydes with formula C5H10O (e) Esters with formula C4H8O2 (f ) Ethers with formula C4H10O

Draw compounds that contain the following: (a) A primary alcohol (b) A tertiary nitrile (c) A secondary thiol (d) Both primary and secondary alcohols (e) An isopropyl group (f ) A quaternary carbon

Draw and name all monobromo derivatives of pentane, C5H11Br

Draw and name all monochloro derivatives of 2,5-dimethylhexane, C8H17Cl.

Draw structures for the following: (a) 2-Methylheptane (b) 4-Ethyl-2,2-dimethylhexane (c) 4-Ethyl-3,4-dimethyloctane (d) 2,4,4-Trimethylheptane (e) 3,3-Diethyl-2,5-dimethylnonane (f ) 4-Isopropyl-3-methylheptane

Draw a compound that: (a) Has only primary and tertiary carbons (b) Has no secondary or tertiary carbons (c) Has four secondary carbons

Draw a compound that: (a) Has nine primary hydrogens (b) Has only primary hydrogens

Give IUPAC names for the following compounds: (a) CH3 CH3CHCH2CH2CH3 CH3 (b) CH3CH2CCH3 CH3 CH3 (c) CH3 CH3CHCCH2CH2CH3 H3C (d) CH2CH3 CH3CH2CHCH2CH2CHCH3 CH3 CH3 (e) CH3CH2CH2CHCH2CCH3 CH2CH3 H3C CH3 CH3 (f) CH3 CH3C CCH2CH2CH3

Name the five isomers of C6H14.

Explain why each of the following names is incorrect: (a) 2,2-Dimethyl-6-ethylheptane (b) 4-Ethyl-5,5-dimethylpentane (c) 3-Ethyl-4,4-dimethylhexane (d) 5,5,6-Trimethyloctane (e) 2-Isopropyl-4-methylheptane

Propose structures and give IUPAC names for the following: (a) A diethyldimethylhexane (b) A (3-methylbutyl)-substituted alkane

Consider 2-methylbutane (isopentane). Sighting along the C2C3 bond: (a) Draw a Newman projection of the most stable conformation. (b) Draw a Newman projection of the least stable conformation. (c) If a CH3 CH3 eclipsing interaction costs 11 kJ/mol (2.5 kcal/mol) and a CH3 CH3 gauche interaction costs 3.8 kJ/mol (0.9 kcal/mol), make a quantitative plot of energy versus rotation about the C2C3 bond.

What are the relative energies of the three possible staggered conformations around the C2C3 bond in 2,3-dimethylbutane? (See Problem 3.42.)

Construct a qualitative potential-energy diagram for rotation about the CC bond of 1,2-dibromoethane. Which conformation would you expect to be most stable? Label the anti and gauche conformations of 1,2-dibromoethane.

Which conformation of 1,2-dibromoethane (Problem 3.44) would you expect to have the largest dipole moment? The observed dipole moment of 1,2-dibromoethane is m51.0 D. What does this tell you about the actual conformation of the molecule?

Draw the most stable conformation of pentane, using wedges and dashes to represent bonds coming out of the paper and going behind the paper, respectively.

Draw the most stable conformation of 1,4-dichlorobutane, using wedges and dashes to represent bonds coming out of the paper and going behind the paper, respectively.

For each of the following compounds, draw an isomer that has the same functional groups. OH N CH3CH2CHO CH3 CH3CHCH2CH2Br (a) (b) (c) CH3CH2CH2C (d) (e) (f) OCH3 CH2CO2H

Malic acid, C4H6O5, has been isolated from apples. Because this compound reacts with 2 molar equivalents of base, it is a dicarboxylic acid. (a) Draw at least five possible structures. (b) If malic acid is a secondary alcohol, what is its structure?

Formaldehyde, H2C5O, is known to all biologists because of its usefulness as a tissue preservative. When pure, formaldehyde trimerizes to give trioxane, C3H6O3, which, surprisingly enough, has no carbonyl groups. Only one monobromo derivative (C3H5BrO3) of trioxane is possible. Propose a structure for trioxane.

The barrier to rotation about the CC bond in bromoethane is 15 kJ/mol (3.6 kcal/mol). (a) What energy value can you assign to an HBr eclipsing interaction? (b) Construct a quantitative diagram of potential energy versus bond rotation for bromoethane.

Increased substitution around a bond leads to increased strain. Take the four substituted butanes listed below, for example. For each compound, sight along the C2C3 bond and draw Newman projections of the most stable and least stable conformations. Use the data in Table 3.5 to assign strain energy values to each conformation. Which of the eight conformations is most strained? Which is least strained? (a) 2-Methylbutane (b) 2,2-Dimethylbutane (c) 2,3-Dimethylbutane (d) 2,2,3-Trimethylbutane

The cholesterol-lowering agents called statins, such as simvastatin (Zocor) and pravastatin (Pravachol), are among the most widely prescribed drugs in the world, with annual sales estimated at approximately $15 billion. Identify the functional groups in both, and tell how the two substances differ.

Well look in the next chapter at cycloalkanessaturated cyclic hydrocarbons and well see that the molecules generally adopt puckered, nonplanar conformations. Cyclohexane, for instance, has a puckered shape like a lounge chair rather than a flat shape. Why?

Well see in the next chapter that there are two isomeric substances both named 1,2-dimethylcyclohexane. Explain. CH3 CH3 H 1,2-Dimethylcyclohexane