《有机化学》英文教学课件：Chap 7 Alcohols, Phenols, Ethers(2012b-醇酚)

1、1,Chap 7 Alcohols, Phenols, Ethers,2,Section 1 Alcohols,. Structure,Classification and Nomenclature,OH hydroxyl,3,4,Alcohol are named systemically by dropping the final “e” of the parent hydrocarbon and adding the suffix “ol.” The functional group, OH(hydroxyl), is given the lowest number possible,

2、taking precedence over other groups in the molecule. The longest carbon chain is identified and the substituents numbered appropriately.,5,methanol,ethanol,6,3-chloro-4-fluoro-2-pentanol,7,4-methyl-4-hexene-2-ol,not 3-methyl-2-hexene-5-ol,3-methylcyclopentanol,8,. Preparation of Alcohol,1. From alke

3、ne,The elements of water can be added to the alkenes in the presence of acid (the common one is sulfuric acid.) The addition is Markovnikovs addition.,9,2. From alkyl halides,Displacement of primary or secondary halides by hydroxide leads to alcohol. But tertiary halides are seldom used due to the e

4、limination reaction complicate the process and lower the yield.,10,3. From carbonyl compounds,Reduction of aldehydes or ketones by hydrogen leads to primary or secondary alcohols.,11,Aldehydes or ketones react with Grignard reagents can get secondary or tertiary alcohols.,12,. Physical Properties,1.

5、 The boiling points of alcohols are much higher than the boiling points of corresponding alkane.,CH3CH2CH3 M=44 b.p= -42.2,CH3CH2OH M=46 b.p= 78.5,13,These special physical properties are due to the existence of hydrogen bonding. The basic oxygen atoms form partial bonds to the acidic hydroxyl hydro

6、gens. Hydrogen bonds are quite strong, on the order of 5 kcal/mol, a value not enough to make permanent dimeric or polymeric structures, but quite sufficient to raise the boiling points of alcohols. It needs the energy to break the hydrogen bonds to make all molecules separate reciprocally so the al

7、cohols can boil.,14,acts as base (proton acceptor),acts as acid (proton donor),hydrogen bonds,15,2. Alcohols are quite water soluble, and most of the smaller molecules are miscible with, or at least highly soluble in water.,16,hydrogen bonds,hydrogen bonds,17,Alcohols create hydrogen bonds with wate

8、r make them easily dissolve in water. Smaller alcohols are miscible, but the molecules become bigger, the effects of alkyl groups R become stronger. We have known that the alkyl groups are water insoluble, so the bigger alcohols are difficult to dissolve in water or water insoluble.,18,The functiona

9、l group of the alcohols is the hydroxyl group, -OH. Unlike the alkyl halides, this group has two reactive covalent bonds, the C-O bond and the O-H bond. The electronegativity of oxygen is substantially greater than that of carbon and hydrogen. Consequently, the covalent bonds of this functional grou

10、p are polarized so that oxygen is electron rich and both carbon and hydrogen are electrophilic, as shown in the drawing on the right.,19,20,. Chemical Properties,21,1. Rupture of OH bond,sodium alcoholate,22,The acidity of alcohols are weaker than the acidity of water, because the alkyl group R is e

11、lectron donating, the inductive effect makes the O-H bond more strong, so alcohols are more difficult to give the proton than water.,23,2. Rupture of CO bond,(1) Halogenation,Almost all alcohols react with halogen acids are SN1 reaction with exception of methanol and most primary alcohols.,24,25,Whe

12、n alcohols react with halogen acids, sometimes will cause rearrangement due to the produce of carbocations (carbocations tend to rearrangement to make them more stable.),26,27,To avoid rearrangement, we can use thionyl chloride (SOCl2) or phosphorus trihalides (PX3) to instead of halogen acids (HX.)

13、,28,Hydrochloric acid/dry zinc chloride which is called Lucas reagent.,29,Because the Chlorohydrocarbons are indissolvable in hydrochloric acid, if the alcohol reacts with Lucas reagent, you will see the reaction solution divide into tow layers or the solution become turbidness. So we can use this r

14、eagent to distin-guish primary, secondary and tertiary alcohols.,30,1) Tertiary alcohols react with Lucas reagent at once and release heat.,2) Secondary alcohols react with Lucas reagent within 5 minutes and no obvious heat release.,3) Primary alcohols do not react with Lucas reagent at room tempera

15、ture even after one hour.,31,(2) Dehydration,A. intermolecular,conc. H2SO4 is concentrated sulfuric acid.,32,B. intramolecular,The intramolecular dehydration of alcohol is Saytzeff elimination. The mechanism is E1 reaction, so the rate is: tertiary secondary primary,33,34,What we concern about is th

16、e intramolecular dehydration. So when we do homework or test paper, always give the intramolecular dehydration products in the dehydration reaction of alcohols unless we point out the reaction is intermolecular reaction.,35,(3) React with inorganic oxacid (esterification),nitrous acid,nitric acid,Th

17、ese two products are famous angiomyocardiac ( medicines for heart and blood vessel.),amyl nitrite,trinitroglycerin,36,Ascanio Sobrero 索布雷罗,Alfred Noble 诺贝尔,37,1998年诺贝尔医学奖,Nitroglycerin was synthesized in 1846, and was first used to treat anginal attacks in 1879.,Louis J. Ignarro 伊格纳罗,Ferid Murad 慕拉德

18、,Robert F. Furchgott 弗奇戈特,38,coordinate bond,phosphoric acid,sulfuric acid,39,The above acids have two or three hydroxyls, so they can react with two or three molecules of alcohol.,(dimethyl sulfate),40,phosphatidate (磷脂),41,phosphatidylcholine (磷脂酰胆碱，卵磷脂),42,nucleotides of DNA,nucleotides of RNA,43

19、,3. Oxidation reaction,44,Collins reagent (chromium trioxide in pyridine),45,4. React with cupric hydroxide and periodic acid,The salt is blue color, so you can use this reaction to distinguish 1,2-glycols.,46,When a 1,2-diol is oxidized by periodic acid (HIO4) it is cleaved to a pair of carbonyl co

20、mpound. This reaction has long been used as a test for 1,2-diols.,47,The general reaction,A specific example,48,49,Clenbuterol (克仑特罗；盐酸双氯醇胺；克喘素；氨哮素；氨必妥 ),肾上腺素能激动剂。可选择性激动2 -受体，而舒张支气管平滑肌 ，用于支气管哮喘，慢性支气管炎，肺气肿和其他肺部疾病引起的支气管痉挛。,50,李富玉,佟文,51,Ractopamine, 莱克多巴胺,52,Terbutaline，特布他林,Salbutamol ，沙丁胺醇，柳丁氨醇，舒喘宁,5

21、3,Phenylpropanolamine (苯丙醇胺),PPA,54,Section 2 Mercaptan,. Chemical Properties of Mercaptans,1. weak acid,Question: Alcohols and mercaptans, which acidity are stronger? How do you know?,55,2. React with heavy metal,56,dimercaptopropanol or BAL,BAL come from British Anti Lewisite. It is usually used a

22、s a antidote when someone is toxicosis of heavy metal.,57,3. Oxidation,disulfide,58,Exercise page 111 7-4 (1-4) 7-5 (1, 2, 7, 8) 7-6 7-8 7-9 7-10,59,Section 2 Phenols,. Nomenclature,phenol,3-methylphenol,1.3-benzenediol or m-hydroxyphenol,60,-naphthol,-naphthol,61,epinephrine, adrenaline,norepinephr

23、ine, noradrenaline,o-hydroxyphenol, catechol,62,isoprenaline, synthetic medicine,Dopamine (DA), the decrease of DA will cause parkinsonism.,63,Bisphenol A,BPA, 双酚,Polycarbonate，PC，聚碳酸酯,64,65,66,Polyethylene terephthalate PETE, 聚对苯二甲酸乙二醇酯,High-density polyethylene HDPE, 高密度聚乙烯,Low-density polyethylen

24、e LDPE, 低密度聚乙烯塑料,Polypropylene PP, 聚丙烯,67,Polystyrene PS, 聚苯乙烯,Polycarbonates PC, 聚碳酸酯,Polyvinyl chloride PVC, 聚氯乙烯,68,69,. Preparation,70,71,. Chemical Properties,1. slightly acid,+ H2O,72,more strong acid react with more strong base to get weaker acid and weaker base,sodium bicarbonate,73,Sequence

25、 of acidity:,is a symbol which combine A and R together, it means aryl groups or aliphatic groups.,74,2. oxidation,Phenols are rather easily oxidized despite the absence of a hydrogen atom on the hydroxyl bearing carbon.,75,p-benzoquinone,hydroquinone,(1,4-benzoquinone),76,77,The quinone-hydroquinon

26、e redox equilibrium is a very important reaction in the respiratory chain in the body of animals.,78,3. Substitution Reaction,79,The o-nitrophenol can create intramolecular hydrogen bond. But the p-nitrophenol create intermolecular hydrogen bond, the boiling point is higher than it of o-nitrophenol. We can separate these two compounds by fractionation.,80,white precipitation,2,4