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alcohols. p799 (special). p798 (special)**. Carboxylic acid. Amide. p814. p795-6 acid and base. p794-5. p803 - need to work out. p802. p810 acid and base. Acid chloride. p795 – need to work out. p807 – need to work out. Ester. Acid anhydride.
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alcohols p799 (special) p798 (special)** Carboxylic acid Amide p814 p795-6 acid and base p794-5 p803 - need to work out p802 p810 acid and base Acid chloride p795 – need to work out p807 – need to work out Ester Acid anhydride
Chapter 21 – addition then R drops off - substitution 1. R- is halide – Acid Halides 2. R – is RCOO – Acid anhydride (same as 1) 3. R- is RO - ester 4. R- is RNH – amide (same as 3) 5. R- is OH – carboxylic acid Increasingly unreactive
Chapter 21 – addition then R drops off - substitution 1. R- is halide – Acid Halides Nu is H2O - Hydrolysis of Acid halides (21.4 p.802 – top) Nu is ROH – Esterification/alcoholysis (p 802 – bottom) Nu is RCOOH – Acid anhydride (p 802 middle) Nu is amine - amide/amminolysis (p 803)
Chapter 21 – addition then R drops off - substitution 2. R- is carboxylate – Acid anhydride (mechanism exactly same as acid chloride) – carboxylate not so good leaving group so Slightly less reactive. Nu is H2O - Hydrolysis of Acid anhydride (p 806 bottom) Nu is ROH – Esterification/alcoholysis (p 807 – top) Nu is amine - amide/amminolysis (p 807 - middle) Classwork: 21.14
Chapter 21 – addition then R drops off - substitution R- is alkoxide – Ester alkoxide not so good leaving group so must be catalysed by acid or base Slightly less reactive. Nu is H2O - Hydrolysis of ester base (Fig 21.7) / acid (Fig 21.8) Nu is ROH – trans esterification/alcoholysis Nu is amine - amide/amminolysis Classwork: 21.43
Chapter 21 – addition then R drops off - substitution R- is amine – amide amine not so good leaving group so must be catalysed by acid or base Slightly less reactive – exactly same mechanism as ester Nu is H2O - Hydrolysis of ester / acid (p 814)
Chapter 21 – addition then R drops off - substitution R- is OH – Carboxylic acid OH very bad leaving group so must be converted into a good leaving group by reacting with some reagent Nu is ROH - Esterification / acid catalysed (Fig 21.4) Nu is “amine” – induction with DCC (Fig 21.5) Nu is ‘halide” - SOCl2 (p 795 top) Classwork: 21.36(h); 21.41
Chapter 21 – addition then R drops off - substitution Other types of nucleophiles (not covered in this module) “hydride ion” - reduction with LiAlH or NaBH4 Grignard reagent and other organometallics Homework: 21.44, 21.48, 21.52