Chapter 3 Drawing Chemical Structures And Classification of Organic Chemistry 2.1 Drawing Chemical Structures 2.2 Classification of Organic Chemistry

2.1.4 Hydrocarbons... compounds composed of carbon and hydrogen. Saturated: carbon-carbon bonds are all single - alkanes [C n H 2n+2 ] Saturated

Hydrocarbons (continued) Unsaturated: contains carbon-carbon multiple bonds. Unsaturated

Alkanes the general formula C n H 2n+2 saturated hydrocarbons All the carbon atoms in an alkane are sp 3 hybridized and tetrahedral in shape. Cycloalkanes alicyclic compounds) the general formula C n H 2n

X

Alkyl groups Alkyl groups (CnH2n+1) are alkane substituents of a complex molecule. CH 3, CH 2 CH 3,CH 2 CH 2 CH 3,

Classes of Compounds Classification based on functional group Three broad classes  Hydrocarbons  Compounds containing oxygen  Compounds containing nitrogen => 2.2 Classification of Organic Chemistry

2.2.1 Hydrocarbons Alkane: single bonds, sp 3 carbons Cycloalkane: carbons form a ring Alkene: double bond, sp 2 carbons Cycloalkene: double bond in ring Alkyne: triple bond, sp carbons Aromatic: contains a benzene ring =>

2.2.2 Compounds Containing Oxygen Alcohol: R-OH Ether: R-O-R' Aldehyde: RCHO Ketone: RCOR' =>

2.2.4 The Common Functional Groups ClassGeneral Formula HalohydrocarbonsR  X AlcoholsR  OH EthersR  O  R Aldehydes

ClassGeneral Formula Ketones Carboxylic Acids Esters Amines R  NH The Common Functional Groups

● functional groups involving double bonds and which contain oxygen

醛 酮 羧酸

酰氯 酸酐 酯

酰胺 酚 ROR 醚 Ether

Nitrile 睛 Alcohol or akanol 醇 Amine 胺 Nitro 硝基化合物

醛 酮 羧酸 酰氯 酸酐 酯 酰胺 酚

● functional groups which contain a halogen atom

Functional groups can be classed as aliphatic or aromatic. Aliphatic functional groups( 脂肪族官能团） the aromatic ring is attached to the heteroatom

Aromatic functional groups the aryl group is directly attached to the carbonyl end of the functional group

Primary( 伯 ), secondary( 仲 ), tertiary( 叔 ), or quaternary( 季 ) nomenclature The primary (1), secondary (2), tertiary (3) and quaternary (4) nomenclature is used in a variety of situations: to define a carbon center, or to define functional groups such as alcohols, halides, amines and amides. Identifying functional groups in this way can be important since the properties and reactivities of these groups may vary depending on whether they are primary, secondary, tertiary, or quaternary. One of the easiest ways of determining whether a carbon center is 1, 2, 3 or 4 is to count the number of bonds leading from that carbon center to another carbon atom 数 C-C 数量

数 N-C 数量 Amines and amides

数 C-C 数量 Alcohols and halides