厦门大学化学化工学院：《有机化学》课程教学资源（课件讲稿，双语版）第四章 烷烃 命名 构象分析及合成导论（4.1-4.3）Introduction to Alkanes and Cycloalkanes

HH CHCC Chapter 4 Alkanes. 2-methyl-4-p Nomenclature,H Conformational Analysis, and an Introduction'tetsynthesis H Cl 烷烃:命名、构象分析及合成导论

Chapter 4 Alkanes: Nomenclature, Conformational Analysis, and an Introduction to Synthesis 烷烃 命名 构象分析及合成导论

ORGANIC CHEMISTRY Chapter 4 4.1 Introduction to alkanes and Cycloalkanes Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 4 4.1 Introduction to Alkanes and Cycloalkanes

ORGANIC CHEMISTRY Chapter 4 4.1A Sources of alkanes petroleum o The primary source of alkanes is petroleum o Natural gas consists chiefly of methane, but ethane, propane, butane, and isobutane are also present o Petroleum is a complex mixture of hydrocarbons that must be refined into different fraction before it can be used Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 4 4.1A Sources of Alkanes: Petroleum The primary source of alkanes is petroleum Natural gas consists chiefly of methane, but ethane, propane, butane, and isobutane are also present. Petroleum is a complex mixture of hydrocarbons that must be refined into different fraction before it can be used

ORGANIC CHEMISTRY Chapter 4 4. IB Petroleum Refining(精炼) AsI p halt lubricating oil waxes Gas oil (C1-C Petroleum K erosene (C1-C14 Straight-run gasoline (C5-C1) Natural gas Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 4 4.1B Petroleum Refining (精炼) Asphalt Asphalt Petroleum Petroleum Natural gas (C1 – C4) Natural gas (C1 – C4) Straight-run gasoline (C5 – C11) Straight-run gasoline (C5 – C11) Kerosene (C11 – C14) Kerosene (C11 – C14) Gas oil (C14 – C25) Gas oil (C14 – C25) Lubricating oil waxes Lubricating oil waxes

ORGANIC CHEMISTRY Chapter 4 4 IC Cracking(裂化) o Catalytic cracking-gas oil fraction is heated at 400- 500C in the presence of catalysts and cracking into smaller molecules suitable for use in gasoline Thermal cracking一 in the absence of a catalysis- unbranched alkanes- low octane ratin Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 4 4.1C Cracking (裂化) Catalytic cracking — gas oil fraction is heated at 400 ~ 500 in the presence of catalysts and “cracking” into smaller molecules suitable for use in gasoline Thermal cracking — in the absence of a catalysis — unbranched alkanes — low “octane rating

ORGANIC CHEMISTRY Chapter 4 octane(异辛烷) CH3 CH3 CH3C-CH2CHCH3 CH 3 Isooctane (2, 2, 4-trimethylpentane) cane rating(辛烷值)=100 Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 4 Isooctane (异辛烷) CH3 C CH2CHCH3 CH3 CH3 CH3 Isooctane (2,2,4-trimethylpentane) Octane rating (辛烷值)= 100

ORGANIC CHEMISTRY Chapter 4 4.2 Shapes of alkanes Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 4 4.2 Shapes of Alkanes

ORGANIC CHEMISTRY Chapter 4 o Straight-chain alkanes norma alkanes o Unbranched-chain alkanes o Constitutional isomers CH3-CH,-CH-CH,CH, n-Pentane CH3-CH-CH2-CH3 Isopentane CH CH3 CH3-C-CH Neopentane CH Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 4 Straight-chain alkanes — “normal” alkanes Unbranched-chain alkanes Constitutional isomers CH3 CH2 CH2 CH2 CH3 n-Pentane CH3 CH CH2 CH3 CH3 Isopentane CH3 C CH3 CH3 CH3 Neopentane

ORGANIC CHEMISTRY Chapter 4 Constitutional isomers Isomers Di diastereomers Stereo isomers Enantiomers Conformers Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 4 Constitutional isomers Isomers Isomers Diastereomers Stereo isomers Enantiomers Conformers

ORGANIC CHEMISTRY Chapter 4 o Constitutional isomers are always found to have different physical properties(melting points boiling points, densities, indexes of refraction) compounds mp(℃C)bp(℃) 95 68.7 0.6594 153.760.3 0.6532 118 63.3 0.6643 128.858 0.6616 98 497064921.3688 Department of Chemistry, Xiamen University

ORGANIC CHEMISTRY Department of Chemistry, Xiamen University Chapter 4 Constitutional isomers are always found to have different physical properties (melting points, boiling points, densities, indexes of refraction) -98 49.7 0.6492 1.3688 -128.8 58 0.6616 1.3750 -118 63.3 0.6643 1.3765 -153.7 60.3 0.6532 1.3714 -95 68.7 0.6594 1.3748 bp( d nD compounds mp( ) )