Chapter 17 Aldehydes and Ketones I Naming and Structure 1 Naming 17 1 A Aldehydes get an al ending if substituent formyl B Ketones are named as substituents ketone or an oxo substituent or with and one ending 2 Structure 17 2 carbonyls are planar sp2 polarized through induction resonance II Preparation of Aldehydes and Ketones 17 4 table 17 2 1 Oxidation of alcohols A Chromium reagents 8 6 B Manganese reagents selective allylic OH oxidation 2 Ozonolysis 12 12 3 Hydration of Alkynes 13 7 and 13 8 A Markovnikov B Anti markovnikov 4 F C Acylation 15 3 III Reactivity and Mechanism 17 5 1 Multiple sites of reactivity 2 Addition reactions obey a general mechanism A Nucleophilic addition protonation mechanism basic B Electrophilic protonation addition acidic C Neutral IV Addition of oxygen nucleophiles 1 Addition of Water hydrate formation 17 6 A Mechanism base catalyzed aqueous OH H2O NaOH B H catalyzed mechanism H3O H2O HCl C Reversibility 1 Alkyl groups stabilize carbonyls 2 Aldehydes are more electropositive 2 Addition of Alcohols hemiacetals and acetals 17 7 A Hemiacetals are half an acetal B Acetals have two alcohols being added C Mechanism 3 Acetals as protecting groups 17 8 4 Thioacetals A Sulfur analogs of acetals B Hydrolysis V Addition of Amines and Ammonia 17 9 1 Imines condensation reaction with a primary amine or NH3 A Mechanism acidic 2 Imine Derivatives 3 Enamines reaction with a secondary amine B Mechanism C Useful alkylating agents 18 4 4 Tertiary amines will not react VI Other reaction of carbonyls 1 Wol Kishner Reduction 17 10 A Mechanism 2 Cyanohydrins 17 11 A Add CN to a carbonyl 3 The Wittig reaction 17 12 A Addition of a phosphonium ylide to a carbonyl B Mechanism 1 ylide formation 2 Alkene formation C Regioselectivity D Stereochemistry 1 Stabilized ylide stable products trans 2 Unstabilized ylide unstable products cis 3 Resonance induction 4 Baeyer Villiger Oxidation 17 13 A Oxidize ketones or aldehydes to esters COOH B Migratory Aptitude cation like VII Chemical Tests for Aldehydes 17 14 1 Fehling s Test 2 Tallen s Test
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