有機化合物分子的結(jié)構(gòu)基礎(chǔ)ppt課件

1、第一章第一章 有機化合物分子的有機化合物分子的結(jié)構(gòu)基礎(chǔ)結(jié)構(gòu)基礎(chǔ)第一章重點講解問題n1. 簡要回顧有機化學(xué)的形成，并回答有機簡要回顧有機化學(xué)的形成，并回答有機化學(xué)是怎樣的一門學(xué)科化學(xué)是怎樣的一門學(xué)科n2. 價鍵理論基礎(chǔ)回顧和分子軌道理論簡介價鍵理論基礎(chǔ)回顧和分子軌道理論簡介n3. 雜化軌道理論與有機化合物結(jié)構(gòu)特點雜化軌道理論與有機化合物結(jié)構(gòu)特點n4. 有機化合物的基本骨架和官能團有機化合物的基本骨架和官能團n5. 有機化合物的結(jié)構(gòu)與性質(zhì)的關(guān)系有機化合物的結(jié)構(gòu)與性質(zhì)的關(guān)系n 1、價鍵、價鍵 2、非共價力、非共價力 3、立體結(jié)構(gòu)、立體結(jié)構(gòu) n6. 質(zhì)子酸堿和路易斯酸堿理論質(zhì)子酸堿和路易斯酸堿理論1.

2、1 有機化學(xué)及其發(fā)展歷史和趨勢n1. HistorynIn 1770, Swedish chemist Torberm Bergman was the first to express the difference between “organic” and “inorganicsubstances1.1 有機化學(xué)及其發(fā)展歷史和趨勢nOrganic -n derived from living organismnOriginally, nStudy of compounds extracted from living organisms and their natural products 1

3、.1 有機化學(xué)及其發(fā)展歷史和趨勢nVital force theory: nOrganic compounds needs a “vital force” to create them1.1 有機化學(xué)及其發(fā)展歷史和趨勢nIn 1828, Fridrich Wohler convert the “inorganic” salt ammonium cyanate into the “organic” substance ureaNH4+ -OCNNH2ONH2 Heat1.1 有機化學(xué)及其發(fā)展歷史和趨勢nWohlers synthesis led to the realization that m

4、olecules found in nature can be described, handled, and synthesized in the same way as minerals and metals. What an astounding insight-that atoms and molecules move freely between the living and nonliving worlds, that the living and nonliving share fundamental attributes that can be studied. With th

5、is discovery, organic chemistry was born.1.1 有機化學(xué)及其發(fā)展歷史和趨勢n作業(yè)作業(yè) 1：n查閱有關(guān)書籍和文獻，了解有機化學(xué)的發(fā)查閱有關(guān)書籍和文獻，了解有機化學(xué)的發(fā)展歷史和趨勢。并就發(fā)展歷史中可以稱之展歷史和趨勢。并就發(fā)展歷史中可以稱之為里程碑的一個發(fā)現(xiàn)作介紹和評述。為里程碑的一個發(fā)現(xiàn)作介紹和評述。n字數(shù)要求在字數(shù)要求在1500字以內(nèi)字以內(nèi),第六周周三交第六周周三交1.1 有機化學(xué)及其發(fā)展歷史和趨勢n2. Definition of Organic ChemistrynOrganic Chemistry is the Chemistry of Carb

6、on Compounds Organic Chemistry is the Chemistry of Carbon CompoundsnQuestion: nWhy is an entire branch of chemistry devoted to the study of carbon-containing compounds?Organic Chemistry is the Chemistry of Carbon CompoundsnThe answer is :nCarbon-containing compounds makes life possiblenWe need carbo

7、n-containing compounds in nature for our food, medicines, clothing, and energynWe depend on millions of synthetic carbon -contaning compounds in our daily lifeOrganic Chemistry is the Chemistry of Carbon CompoundsnQuestion: nWhat makes carbon so special?nWhy are there so many carbon-containing compo

8、unds?Organic Chemistry is the Chemistry of Carbon CompoundsnPlease try to draw out all the structures corresponding to the formula: na. C2H6Onb. C3H6OnIt shares electrons with other carbon atoms nIt shares electrons with several kinds of atomsnC-C single, double and triple bondnchain, or cyclo-links

9、 nIsomerism phenomenonC2H6O: CH3OCH3 CH3CH2OH C3H6O: CH2=CHOCH3 CH2=CHCH2OH CH3C(OH)=CH2 CH3CH=CHOH CH3COCH3 CH3CH2CHO CH3HHHOHHCH3HOOHOCCHOHHCH3CCOHHHCH31.2 價鍵理論基礎(chǔ)回顧和分子軌道理論簡介n1.2.1 The Structure of an Atomn1.2.2 Distribution of Electrons in an Atom nAtomic orbitals: sp (px,py,pz)d (dx,dy,dz,d , d )

10、x2-y2z21.2 價鍵理論基礎(chǔ)回顧和分子軌道理論簡介n(1) The aufbau priciplenThe closer the orbital is to the nucleus, the lower its energyn1s2s2p3s3p4s3d4p5s4d5p6sn(2) The Pauli exclusion priciplenDegenerate orbitals - have the same energyn(3) Hunds rulenC: 1s2 2s2 2px12py12pz01.2 價鍵理論基礎(chǔ)回顧和分子軌道理論簡介n1.2.3 Ionic, Covalent,

11、and Polar BondsnAn atom is most stable if it has a filled shell or an outer shell of eight electrons and no electrons of higher energynIonic bond: LiClnCovalent bond: H2, O2, CO2 n C: 1s2 2s2 2px12py12pz0n Neither readily gives up electrons n Nor readily accepts electronsnNonpolar bond (H-H)and Pola

12、r bond ( C-H, C-O )1.2 價鍵理論基礎(chǔ)回顧和分子軌道理論簡介n常見價鍵的表示方法：常見價鍵的表示方法：nLewis StructuresnKekule StructuresnCondensed StructuresCOHOHH C OOHH C OOHHCO2H1.2 價鍵理論基礎(chǔ)回顧和分子軌道理論簡介n思考題思考題n共價鍵化合物與離子鍵化合物性質(zhì)有哪些差異？共價鍵化合物與離子鍵化合物性質(zhì)有哪些差異？n請記住有機化合物中常見元素的電負性請記住有機化合物中常見元素的電負性nElectronegativity:nH: 2.1 B: 2.0 C: 2.5 N: 3.0 O: 3.

13、5nF: 4.0 Cl: 3.0 Br: 2.8 I: 2.5nLi: 1.0 Mg: 1.21.2 價鍵理論基礎(chǔ)回顧和分子軌道理論簡介n1.2.4 Introduction of Molecular TheorynOrbitals are conserved - the number of atomic orbitals combined must equal the number of molecular orbitals formed=H HH : H1s atomic orbital1s atomic orbitalbonding molecular orbital.1.2.4 Int

14、roduction of Molecular TheorynThe above only shows the bonding molecular orbital, the other one is antibonding molecular orbital, but it contains no electrons.H HH : H1s atomic orbital1s atomic orbitalbonding molecular orbital.antibonding molecular orbital1.2.4 Introduction of Molecular TheorynThe 1

15、s atomic orbitals can combine in one of two ways+wave reinforce each other, resulting in bonding+nodewave cancel each otherand no bond forms1.2.4 Introduction of Molecular Theoryn- The 1s atomic orbitals combine in a way that enhance each other, similar to two light waves or two sound waves that rei

16、nforce each other. It is a sigma bonding molecular orbital 鍵鍵 n- The 1s atomic orbitals can also combine in a way that cancel each other, producing a node between the nuclei. It is a sigma antibonding molecular orbital * 鍵鍵 1.2.4 Introduction of Molecular TheorynSide-to-side overlapping of in-phase

17、p orbitals produces a bonding pi- molecular orbital 鍵鍵 nSide-to-side overlapping of out-of-phase p orbitals producing an antibonding pi- molecular orbital * 鍵鍵 2p atomic orbital2p atomic orbitalbonding pi-molecular orbitalantibonding pi- molecular orbital1.3 碳的雜化軌道理論 Hybridizationn1.3.1 sp3 Hybridiz

18、ationnC 1s22s22p2 - 2s22px12py12pz0 2s12px12py12pz1 n2s + 2px2py2pz 4 sp3 hybridization orbitals neach orbital has one electron 1.3.1 sp3 Hybridizationn to form a tetrahedron carbon (see the structure of methane)HHHHHHHHMirrorHHOCH3CH2ClHOHClH2CH3CMirror1.3.1 sp3 HybridizationnConfiguration isomers

19、- enantiomersn a chiral carbon - a carbon linked with four different kinds of atomsnConformation isomer - ethane1.3.2 sp2 HybridizationnC 1s22s22p2 - 2s22px12py12pz0 2s12px12py12pz1 n2s + 2px2py + 2pz 3 sp2 hybridization orbitals + 1 2pzneach orbital has one electron1.3.2 sp2 Hybridizationnto form a

20、 planer carbon (see the structure of Ethene)nanother kind of stereo-isomer - Geometric Isomerization - cis, transCCHOHHH3CCCOHHHH3C1.3.3 sp Hybridizationnto form a liner carbon (see the structure of Ethyne)nOptical Activity in AllenesCCHHCCCCCC1.3.4 有機化合物異構(gòu)現(xiàn)象 IsomerismC2H6O: CH3OCH3 CH3CH2OH C3H6O:

21、CH2=CHOCH3 CH2=CHCH2OH CH3C(OH)=CH2 CH3CH=CHOH CH3COCH3 CH3CH2CHO H3CHHHOHHCH3HOOHOCCHOHHH3CCCOHHHH3C1.3.4 有機化合物異構(gòu)現(xiàn)象 Isomerismn關(guān)于碳化合物的異構(gòu)問題請參閱 -邢其毅“基礎(chǔ)有機化學(xué)P166n Isomers n Constitutional isomers Stereoisomersn Configurational isomers Conformational isomersn Optical isomers Geometric isomers nEnantiomer

22、s Diastereomers1.4 有機分子的基本骨架和官能團n1.4.1 基本骨架 - 由碳碳鍵和碳氫鍵構(gòu)成n1.4.2 官能團Functional Groups)：n1.4.2.1 Containing Nitrogen: n Amines: RNH2, R2NH, R3N, （R4N+X-）n Imines: -C=NH, -C=NR; n Nitrile: RCN (-CN, cyano group )1.4.2.1 Containing NitrogennThe structure Features:nN: ( 1s2 )2s22p3 n sp3, sp2, sp hybridiz

23、ation n C-N single, double, triple bondn 4 orbitals, but 5 electrons in an atoms there is a lone pair of electronsn Hydrogen-Bond - electronegativitynPolar Covalent Bond - electronegativity1.4.2.2 Containing Oxygenn Ethers R-O-Rn Alcohols R-OHn Aldehydes, Ketones R(H)C=O, R2 C=On Carboxylic Acids an

24、d their Derivatives RCOOH, RCOOR, RCONR2, RCOX1.4.2.2 Containing OxygennThe structure Features:nO: ( 1s2 )2s22p4 n sp3, sp2 hybridization n C-O single, double bondn 4 orbitals, but 6 electrons in an atoms there is two lone pairs of electronsn Hydrogen-Bond - electronegativityn Polar Covalent Bond -

25、electronegativity1.4.2.3 Containing halogennAlkyl Halides +R-X - R+ + X-nStructural Features:nX: ns2np5nhalogen - electronegativity is bigger than carbonnPolar Covalent Bond1.4 有機分子的基本骨架和官能團n以下內(nèi)容請參閱教材第二十五章結(jié)構(gòu)部分n1.4.2.4 Containing Sulfurn1.4.2.5 Containing Phosphorusn1.4.2.6 Containing Boronn1.4.2.7 C

26、ontaining Silison 1.5 有機化合物的結(jié)構(gòu)與性質(zhì)的關(guān)系n1.5.1 共價鍵的結(jié)構(gòu)與性質(zhì)關(guān)系 - nKey Part of Organic Chemistryne.g. 1. Hydrocarbons nAlkanes, Alkenes, Alkynes and AromaticnCH3CH3, CH2=CH2, CH CH, nSubstitute Reaction, Addition Reaction,nC6H6 - Addition, difficult; n Substitution, easy 1.5 有機化合物的結(jié)構(gòu)與性質(zhì)的關(guān)系neg 2 C=O, C=C addi

27、tion reaction n but mechanism are differentneg 3 RH, ROH, RCOOH n acidity increase from left to rightneg 4 Compounds containing O or N, comparing with C, have lone pair of electron, so they often work as Lewis base. n作業(yè)作業(yè)2：n閱讀教材相關(guān)部分，從有機化合物的結(jié)構(gòu)閱讀教材相關(guān)部分，從有機化合物的結(jié)構(gòu)出發(fā)，簡要概括各主要官能團化合物的化出發(fā)，簡要概括各主要官能團化合物的化學(xué)性質(zhì)建

28、議列表格對應(yīng)性質(zhì)與結(jié)構(gòu)特征）學(xué)性質(zhì)建議列表格對應(yīng)性質(zhì)與結(jié)構(gòu)特征）n （第六周交）（第六周交）1.5.2 非共價力與性質(zhì)的關(guān)系n非共價力包括：非共價力包括：n 氫鍵氫鍵 Hydrogen Bondn 范德華作用力范德華作用力 （吸引力和斥力）（吸引力和斥力）n 偶極偶極-偶極作用力等見下表）偶極作用力等見下表）n作用于分子間和分子內(nèi)作用于分子間和分子內(nèi)n影響化合物的物理性質(zhì)和化學(xué)性質(zhì)影響化合物的物理性質(zhì)和化學(xué)性質(zhì)n 熔點、沸點、溶解性能熔點、沸點、溶解性能n 酸堿性、反應(yīng)速度和反應(yīng)方向酸堿性、反應(yīng)速度和反應(yīng)方向非共價力及其強度InteractionsStrength Ion-Ion intera

29、ctioncomparable to covalent bondingIon-dipole50200 kJ/molDipole-dipole550 kJ/molHydrogen bonding4120 kJ/molCation- interactions580 kJ/mol- stacking050 kJ/molvan der Waals forces 5 kJ/mol, variableHydrophobic effects1.5.2 非共價力與性質(zhì)的關(guān)系n氫鍵的飽和性和方向性氫鍵的飽和性和方向性n飽和性飽和性由于氫原子特別小，而原子由于氫原子特別小，而原子A和和B比較大，所以比較大，所以A

30、-H中的氫原子只能和一個中的氫原子只能和一個B原子結(jié)合形成氫鍵；同時，由于負離子之原子結(jié)合形成氫鍵；同時，由于負離子之間的相互排斥，另一個電負性大的原子間的相互排斥，另一個電負性大的原子B 就難于再接近氫原子就難于再接近氫原子.ABBH+1.5.2 非共價力與性質(zhì)的關(guān)系n方向性方向性由于電偶極矩由于電偶極矩A-H與原子與原子B的相的相互作用，只有當(dāng)互作用，只有當(dāng)A-HB在同一直線上時最在同一直線上時最強；同時，由于原子強；同時，由于原子B一般含有未共用電子一般含有未共用電子對，在可能的范圍內(nèi)氫鍵的方向和未共用對，在可能的范圍內(nèi)氫鍵的方向和未共用電子對的對稱軸一致，這樣可使原子電子對的對稱軸一致

31、，這樣可使原子B中負中負電荷分布最多的部分最接近氫原子，這樣電荷分布最多的部分最接近氫原子，這樣形成的氫鍵最穩(wěn)定。形成的氫鍵最穩(wěn)定。1.5.2 非共價力與性質(zhì)的關(guān)系n氫鍵的強弱氫鍵的強弱A、B的電負性越大，氫鍵的電負性越大，氫鍵越強；越強；B的原子半徑越小，氫鍵越強。（的原子半徑越小，氫鍵越強。（F-HF最強）最強）1.5.2 非共價力與性質(zhì)的關(guān)系n氫鍵對分子構(gòu)象的影響氫鍵對分子構(gòu)象的影響HHClOHHHClHHOHHHCH3HHOHHHIIIIII1.5.2 非共價力與性質(zhì)的關(guān)系n氫鍵對互變異構(gòu)平衡的影響氫鍵對互變異構(gòu)平衡的影響H3CCHOH2CCOHHOCCH3H3CH2CCOHCH3OO

32、OOHOOHOOOOH0.000025%1.2%0%92% in hexane16% in water100%1.5.2 非共價力與性質(zhì)的關(guān)系n氫鍵對酸性的影響OOOHHOHHOOO -HOHHHOOHHOOHHOO -HOOHpKa1=1.83; pKa2=6.07pKa1=3.03; pKa2=4.441.5.2 非共價力與性質(zhì)的關(guān)系n天然化合物中的氫鍵舉例核酸結(jié)構(gòu)中的氫鍵；蛋白質(zhì)結(jié)構(gòu)中的氫鍵1.5.3 立體結(jié)構(gòu)與性質(zhì)的關(guān)系OOOHHOHHOOO -HOHHHOOHHOOHHOO -HOOHpKa1=1.83; pKa2=6.07pKa1=3.03; pKa2=4.441.6 質(zhì)子酸堿和路

33、易斯酸堿理論n1.6.1 酸堿概念的發(fā)展n1663年 （英Boyle, R. n 酸具有酸味，能使藍色石蕊變紅n 堿具有苦澀味，能使紅色石蕊變藍n18世紀(jì)后期，從物質(zhì)內(nèi)在性質(zhì)認識酸堿n1781年 （法Lavoisier, A. L.n 酸是一類含氧化合物，氧酸素n19世紀(jì)初，HCl，HI等被發(fā)現(xiàn)n 1811年 Davy, D. P. n 提出“氫是酸的基本元素的論點1.6 質(zhì)子酸堿和路易斯酸堿理論n1.6.1 酸堿概念的發(fā)展n19世紀(jì)后期，近代酸堿理論開始形成nA、1889年 Arrhenius, S. A. 水-離子論n20世紀(jì) nB、 Franklin, F.C. 溶劑論nC、Bronsted, J. N.-Lowry, T. M. 質(zhì)子論nD、Lewis, G. N. 電子論nE、Pearson, R. G. 軟硬酸堿理論1.6 質(zhì)子酸堿和路易斯酸堿理論n1.6.2 Arrihenius 離子論n 在水溶液中能電離出氫離子的物質(zhì)稱為酸；能電離出氫氧根離子的物質(zhì)稱為堿n局限性：n不能解釋非水體系和非溶劑體系的問題（1） C2H5O- Na+ 溶于乙醇（2） 2 Na + 2 NH32 Na + + 2NH2- + H2（3） NH3(g) + HCl(g)NH4+Cl-1.6 質(zhì)子酸堿和路易斯酸