Organic Chemistry, 5th Edition L.G. Wade. jr Chapter 3 Structure and Stereochemistry of alkanes Jo blackburn Richland college, dallas TX Dallas county community college district C 2003. Prentice hall
Chapter 3 Structure and Stereochemistry of Alkanes Organic Chemistry, 5th Edition L. G. Wade, Jr. Jo Blackburn Richland College, Dallas, TX Dallas County Community College District © 2003, Prentice Hall
Alkane formulas All C-C single bonds Saturated with hydrogens ·Rato:C.H n2n+ 2 Alkane homologs: CH3(CH2),CH3 Same ratio for branched alkanes H HhH H H—C-H H—C-C-C—C-H H H H-C-C--C-H HHH H H H H Butane, C 4H10 hapter 3 Isobutane, C4H10
Chapter 3 2 Alkane Formulas • All C-C single bonds • Saturated with hydrogens • Ratio: CnH2n+2 • Alkane homologs: CH3 (CH2 )nCH3 • Same ratio for branched alkanes H C H C H H C H H C H H H H Butane, C 4H10 => H C H C C H H H C H H H H H Isobutane, C 4H10
Common names Isobutane.“ isomer of butane” Isopentane, isohexane, etc, methyl branch on next-to-ast carbon in chain Neopentane, most highly branched Five possible isomers of hexane, 18 isomers of octane and 75 for decane! => Chapter 3
Chapter 3 3 Common Names • Isobutane, “isomer of butane” • Isopentane, isohexane, etc., methyl branch on next-to-last carbon in chain. • Neopentane, most highly branched • Five possible isomers of hexane, 18 isomers of octane and 75 for decane! =>
Pentanes H HHhh H H—C—H H—C—C—C—C—C—H H HH HHhh H H-C-C-C-C-H HH H n-pentane, C5H12 Isopentane, C sH12 CH3 H3C一C-CH3 CH neopentane, C 5H12 Chapter 3
Chapter 3 4 Pentanes H C H C H H C H H C H C H H H H H n-pentane, C5 H12 H C H C C H H C H H H H H C H H H isopentane, C 5 H12 => C CH3 H3C CH3 CH3 neopentane, C 5H12
IUPAC Names Find the longest continuous carbon chain Number the carbons, starting closest to the first branch Name the groups attached to the chain using the carbon number as the locator Alphabetize substituents Use di-, tri-, etc for multiples of same substituent Chapter 3
Chapter 3 5 IUPAC Names • Find the longest continuous carbon chain. • Number the carbons, starting closest to the first branch. • Name the groups attached to the chain, using the carbon number as the locator. • Alphabetize substituents. • Use di-, tri-, etc., for multiples of same substituent. =>