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Chapter 11. Alcohols from carbonyl compounds ( 由羰基化合物制醇). Oxidation-reduction and organometallic compounds ( 氧化 - 还原和有机金属化合物) 11.1 Introduction Carbonyl.

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Presentation on theme: "Chapter 11. Alcohols from carbonyl compounds ( 由羰基化合物制醇). Oxidation-reduction and organometallic compounds ( 氧化 - 还原和有机金属化合物) 11.1 Introduction Carbonyl."— Presentation transcript:

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2 Chapter 11. Alcohols from carbonyl compounds ( 由羰基化合物制醇). Oxidation-reduction and organometallic compounds ( 氧化 - 还原和有机金属化合物) 11.1 Introduction Carbonyl ( 羰基) compounds are a broad group of compounds that includes aldehydes, ketones, carboxylic acids, and esters.

3 11.1A Structure of the carbonyl group

4 11.1B Reaction of carbonyl compounds with nucleophiles

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6 11.2 Oxidation-Reduction reactions in organic chemistry Reduction of an organic molecule usually corresponds to increasing its hydrogen content or to decreasing its oxygen content.

7 The opposite of reduction is oxidation. Thus, increasing the oxygen content of an organic molecule or decreasing its hydrogen content is an oxidation.

8 11.3 Alcohols by reduction of carbonyl compounds

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10 The NaBH 4 is also reduced reagent

11 The mechanism for the reduction of a ketone by sodium borohydride and Lithium aluminum hydride Sodium borohydride (NaBH 4 ) is a milder reducing agent than lithium aluminum hydride (LiAlH 4 ). Lithium aluminum hydride will reduce acids. Esters, aldehydes, and ketones; but sodium borohydride will reduce only aldehydes and ketones.

12 11.4 Oxidation of alcohols Primary alcohols can be oxidized to aldehydes and carboxylic acids.

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14 11.4B Oxidation of 1 o Alcohols to carboxylic acids, Oxidation of 2 o alcohols to ketone.

15 11.4D Mechanism of Chromate oxidations (铬酸氧化机理)

16 11.4E A Chemical test for primary and secondary alcohols

17 11.5 Organometallic compounds (有机金属化合物) Compounds that contain carbon-metal bonds are called organometallic compounds. It include Carbon-lead, carbon-tin, carbon-thallium, carbon-mercury, carbon-lithium and carbon- magnesium bonds.

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19 11.6 Preparation of organolithium and organomagnesium compounds 11.6A Organolithium compounds ( 有机锂化合物) Organolithium compounds are often prepared by the reaction of organic halides with lithium metal.

20 11.6B Grignard reagents (格利 雅试剂) ; Organomagnesium halides were discovered by the French chemist Victor Grignard in Grignard received the Nobel Prize for his discovery in 1912, and organomagnesium halides are now called Grignard reagents in his honor. Grignard reagents have great use in organic synthesis.

21 Grignard reagents are usually prepared by the reaction of an organic halides and magnesium metal in an ether solvent

22 A Grignard reagent forms a complex with its ether solvent; the structure of the complex can be represented as follows:

23 11.7 Reactions of organolithium and organomagnesium compounds 11.7A Reactions with compounds containing acidic hydrogen atoms

24 Grignard reagents and organolithium compounds abstract protons that are much less acidic than those of water and alcohols. They react with the terminal hydrogen atoms of 1-alkynes.

25 11.7B Reaction of Grignard reagents with oxiranes ( 环氧乙烷与格利雅试剂反应) 在合成上增加两个碳原子伯醇

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27 11.7C Reactions of Grignard reagents with Carbonyl Compounds (格利雅试剂与羰基反应)

28 11.8 Alcohols from Grignard reagents 1. A Grignard reagent reacts with formaldehyde to give a primary alcohol ( 伯醇).

29 2. Grignard reagent reacts with higher aldehydes to give secondary alcohol ( 仲醇)

30 3. Grignard reagent reacts with ketones to give tertiary alcohol ( 叔醇)

31 4. A Grignard reagent also adds to the carbonyl group of an ester ( 酯).

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33 11.8 Planning a Grignard synthesis

34 Synthesis of 3-phenyl-3-pentanol

35 Illustrating a Multistep Synthesis ( 举例说明多步合成)

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38 Synthesis of phenyl-acetaldehyde

39 11.8B Restrictions on the use of Grignard reactions

40 11.8C The use of lithium reagents Organolithium reagents (RLi) react with carbonyl compounds in the same way as Grignard reagents.

41 11.8D The use of sodium alkynides ( 炔化钠的使用) Sodium alkynides also react with aldehydes and ketones to yield alcohols.

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