Reações Químicas e Mecanismos

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Solutions to Problems . 381 Then Br + product SN2 CN (b) 2. KCN. DMSO CH₂CO₂H CHCO₂H product Then 1. H₂O. 1 Br₂. cat. P (c) product (Section 9-10) 1. Excess KSH. (d) CH₃COOH Br₂. cat. P BrCH₂COOH product (e) BrCH₂COOH + (CH₃CH₂)₂NH product 1. Br₂. cat. P (f) CH₃CH₂COOH product 48. No tricks here! The mechanism is almost exactly as shown in Section 19-12. with only minor differences. Because the method starts with an alkanoyl halide. step 1 is unnecessary. Step 2 (enolization) occurs as written. The third step uses Cl₂, generated in low concentration from NCS, or Br₂, formed in the same way from NBS. or The fourth step in the mechanism doesn't apply because only alkanoyl halides are present. not carboxylic acids. o H 49. Acidity: > > The most acidic hydrogens in are on the nitrogen. Acidity order is determined by electronegativity. Two protonation possibilities: on N, giving o OH + + and on O. giving Resonance stabilization causes protonation on o to be favored. 50. See Problem 40 in Chapter 17. OH HOCH-CH-CH-CH Initially form