D. A. Evans Other Functional Groups with Non-alternate Reactivity Patterns Chem 206 More Acid Cataly Sulfur Functional Groups Olefins as nucleophiles Simpkins, N. S. Sulfones in Organic Synthesis; Pergamon, 1993 (100%) CH4 Sulfide Mander Smith's cyclopentenone ann pKa (-41) CH3-S-CH3 31*HOH Lindlar's cat(100%) Sulfonium salt Smith,7L19754225 (same acidity as phenol) (- )Reactivity Pattern Rearrangement 2s-C Nonalternate BF3OEt a Reactions with carbonyl compnds Mander. aust. J. chem. 1979 1975 ①W Polyene cyclizations ⊙R2S R2s- Smith, JACS 1981 2009 (一(R O OBF3 N2 S CH3 CH3 CH3 S CH3 Me Me S Me Me C H H CH2 O S Me Me C H H S Me Me S Me Me CH2 O C H H S Me Me S Me Me Me O N2 Me HCl Me Me O N2 BF3 •OEt2 O R N2 O BF3 •OEt2 N2 O O Me Me BF3•OEt2 O Me Me O Me Me O Me Me Cl –N2 O Me Me O O R S O CH3 CH3 O CH3 S CH3 O O CH3 S CH3 O NaH O CH2 R2S C CH2 O R2S C R2S C CH4 HOH NH3 D. A. Evans Other Functional Groups with Non-alternate Reactivity Patterns Chem 206 Sulfur Functional Groups (+) (–) ■ Reactions with carbonyl compnds Nonalternate Reactivity Pattern (–) (+) Simpkins, N. S. Sulfones in Organic Synthesis.; Pergamon, 1993. pKa (~56) pKa 31 pKa (~41) Sulfide Sulfoxide Sulfone Sulfonium Salt pKa (DMSO) ~ 18 ~ 31 (45) ~35 Smith, TL 1975 4225 (40 - 65%) Lindlar's cat. (100%) Smith's cyclopentenone annulation: More Acid Catalysis Olefins as nucleophiles: (100%) Mander Jasmone Mander, Aust. J. Chem. 1979 1975 Rearrangement: Polyene cyclizations: 46% 12% + Smith, JACS 1981 2009 (same acidity as phenol)