H ydrocarbons that contain carbon-carbon triple bond are called alkynes. Non- cyclic alkynes have the molecular formula C, H2n-2. Acetylene (HCCH) is th simplest alkyne. We call compounds that have their triple bond at the end of a carbon chain(RC=CH) monosubstituted, or terminal, alkynes. Disubstituted alkynes (RCCR') are said to have internal triple bonds. You will see in this chapter that a car- bon-carbon triple bond is a functional group, reacting with many of the same reagents

8.1 Chemical Bonds 8.2 Ionic bond, 8.3 Covalent Bonding 8.4 Bond polarity & 8.4 Bond polarity & electronegativity electronegativity 8.5 Lewis Structure

2.1 化学键的定义 Definition of chemical bonding 2.2 共价键的概念与路易斯结构式 Concept of the covalent bond theory and Lewis’ structure formula 2.8 共价分子的性质 Metallic bond theory 2.9 分子间作用力和氢键 Intermolecular forces and hydrogen bonding 2.3 用以判断共价分子几何形 状的价层电子对互斥理论 VSEPR for judging the configuration of the covalence molecular 2.4 原子轨道的重叠 — 价键理论 Superposition of atomic orbital — valence bond theory 2.7 分子轨道理论 Molecular orbital theory 2.5 共轭大π键 Molecular orbital theory 2.6 等电子体原理 Molecular orbital theory

Bond Characteristics reading the financial pages Bond Prices and Yields Bond prices and interest rates YTM vs. current yield Rate of Return Interest Rate Risk The Yield Curve Nominal and Real Rates of Interest Default Risk

§6.2 Valence Bond Theory §6.5 Bond Parameters §6.5 Molecular Orbital Theory §6.4 Valence Shell Electron Pair Repulsion (VSEPR) Theory §6.1 Lewis structure Theory §6.3 Hybrid obits Theory

Chlorotoluene Benzyl chloride Of this group only benzyl chloride is not an aryl halide; its halogen is not attached to the aromatic ring but to an sp-hybridized carbon. Benzyl chloride has the weakest carbon-halogen bond, its measured carbon-chlorine bond dissociation energy being only 293 kJ/mol (70 kcal/mol). Homolytic cleavage of this bond produces a resonance-stabilized benzyl radical

实键(Solid Bond) 双键(Double Bond) 虚键(Dashed Bond)

Functional Group Pi bond is the functional group. · More reactive than sigma bond. · Bond dissociation energies:

Conjugated unsaturated systems have a p orbital on a carbon adjacent to a double bond The p orbital can come from another double or triple bond The p orbital may be the empty p orbital of a carbocation or a p orbital with a single electron in it (a radical)

Alkenes are hydrocarbons whose molecules contain the carbon-carbon double bond. Alkynes are hydrocarbons whose molecules contain the carbon-carbon triple bond