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1559T_ch21_373-38811/9/0516:23Pa9e381 EQA Solutions to Problems.381 44.Analyze the Mannich reaction in terms of the functional unit it constructs 0 Relevant bonds are emphasized in the answers below. CG-G-NGILCID,+ CH2-N(CHa)2 (e)HaN-CH-CN ←NH3+CHCHO+HCN Here the nucleophile is different it is the yanide ion that adds to the iminium arbon. CHCHCLACH-CM-NC CH-CHs 0 CH:CH2CH2CCH2CH2CH3+CH2=O HN(CH3)2 0 0 cHccH:-c-s-at-auec2ciect +2c.-+ CH Two Mannich reactions are involved in this example.Note the primary amine and the presence of two moles each of formaldehyde and acetone. 45.A double Mannich reaction,similar to Problem 44(e): H H.COH2 =0 CH2=C-CH3_ -H% Solutions to Problems • 381 44. Analyze the Mannich reaction in terms of the functional unit it constructs. Relevant bonds are emphasized in the answers below. (a) (b) (c) Here the nucleophile is different; it is the cyanide ion that adds to the iminium carbon. (d) (e) Two Mannich reactions are involved in this example. Note the primary amine and the presence of two moles each of formaldehyde and acetone. 45. A double Mannich reaction, similar to Problem 44(e): O H NHCH3 CH2 CH3 H OH C First Mannich reaction H’s Acetone enol O O H H2NCH3 NHCH3 OH2 H O H After proton transfers H H2O CH2 CH2 CH3 N H CH2CCH3 2NCH3 1. HCl 2. HO 2 CH2  CH3CCH2  2 CH3CCH3  O CH3CH2CH2CCH2CH2CH3  CH2 O HN(CH3)2 CH3CH2CH2CCH CH2CH3 CH2 N(CH3)2 1. HCl 2. HO  H2N CH NH3 CH3 CN CH3CHO HCN CH2 N(CH3)2 HN(CH3)2 1. HCl 2. HO O O CH2 O CH3CCH2 CH2 N(CH2CH3)2 HN(CH2CH3)2 1. HCl 2. HO CH2  CH3CCH3  O H H NH C O H C C O H H N C C C O O C C H H N C 1559T_ch21_373-388 11/9/05 16:23 Page 381
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