Organic Chemistry, 5th Edition L.G. Wade. jr Chapter 6 Alkyl Halides: Nucleophilic Substitution and elimination Jo blackburn Richland college, dallas TX Dallas County Community College District c 2003. Prentice hall
Chapter 6 Alkyl Halides: Nucleophilic Substitution and Elimination Organic Chemistry, 5th Edition L. G. Wade, Jr. Jo Blackburn Richland College, Dallas, TX Dallas County Community College District © 2003, Prentice Hall
Classes of halides Alkyl: Halogen, X, is directly bonded to sp3 carbon Vinyl: X is bonded to sp carbon of alkene Aryl: X is bonded to sp2 carbon on benzene ring. EXamples HH H-C-C-Br HH alkyl halide vinyl halide arvi halide Chapter 6
Chapter 6 2 Classes of Halides • Alkyl: Halogen, X, is directly bonded to sp3 carbon. • Vinyl: X is bonded to sp2 carbon of alkene. • Aryl: X is bonded to sp2 carbon on benzene ring. Examples: C H H H C H H Br alkyl halide C C H H H Cl vinyl halide I aryl halide =>
Polarity and reactivity Halogens are more electronegative than c Carbon-halogen bond is polar, so carbon has partial positive charge Carbon can be attacked by a nucleophile Halogen can leave with the electron pair > 6+ h-C-Br Chapter 6
Chapter 6 3 Polarity and Reactivity • Halogens are more electronegative than C. • Carbon-halogen bond is polar, so carbon has partial positive charge. • Carbon can be attacked by a nucleophile. • Halogen can leave with the electron pair. => C H H H Br + -
Classes of Alkyl Halides Methyl halides: only one C, CH3X Primary: C to which X is bonded has only one C-c bond Secondary: C to which X is bonded has two c-c bonds Tertiary: C to which X is bonded has three c-c bonds Chapter 6
Chapter 6 4 Classes of Alkyl Halides • Methyl halides: only one C, CH3X • Primary: C to which X is bonded has only one C-C bond. • Secondary: C to which X is bonded has two C-C bonds. • Tertiary: C to which X is bonded has three C-C bonds. =>
Classify These CH3--CH-CH3 CH3 CHF (CH3)3 CBr CH3I Chapter 6
Chapter 6 5 Classify These: CH3 CH CH3 Cl CH3 CH2 F (CH3) 3 CBr CH3 I =>