Organic ChemistryIntroduction to Organic Chemistry

Organic Compounds make upFoods and foodstuffFlavours and fragrancesMedicinesMaterials, polymers, plasticsPlant, animal and microbial matter; Fertilizers, natural productsA vast range of manufactured goods[pharmaceuticals, foods, dyestuffs, adhesives, coatings, packaging, lubricants, cosmetics, films & fibres, clothing, etc. etc.]

DNAEssential oilsMedicinesActive Pharmaceutical IngredientsMaterialsFuelsPigmentsSome organic chemicals

An organic compound is one that has carbon as the principal elementAn inorganic element is any compound that is not an organic compound.Carbon is uniqueIt has 6 electrons in its outer shell arranges 1s22s2sp2It has room for 4 bonds to 4 other atoms.Organic compounds have specific geometry around the carbon to carbon bond.If there are four atoms or groups around a carbon atom, it has a tetrahedral geometry.

Carbon Has Four Bonding Electrons

Unique Strong Covalent Bonds Strong Single, Double and Triple Bonds

Carbon4 sp3HybridizationExcited state

lowest energy state

Simplest Organic molecule Covalent Bonding Atoms Share Electrons

Classification of organic compoundsHydrocarbons

Saturated Unsaturated Aromatic

Hydrocarbon Derivatives

HydrocarbonS are compounds consisting of only hydrogen and carbonHydrocarbons can be classified into: Saturated hydrocarbons: Compounds in which carbon bound to carbon by single bonds Unsaturated hydrocarbons: Compounds in which carbon may bound to carbon by double, or triple bondsThe bonds are always nonpolarHydrocarbons

* Saturated hydrocarbons:Have the maximum number of hydrogen atoms attached to each carbon atomAlkanes are hydrocarbons with only C-C single bond.Each successive compound differs from the one before it only by a CH2. CH3CH2CH CH3CH2CH2CH3Propane Butane

Saturated Hydrocarbons

Saturated hydrocarbons can be: Straight Chain:CH3CH2CH2CH3CH3Pentane (Straight Chain) Branched

Closed Ring:

Cycloalkanes

Unsaturated Hydrocarbons:have fewer hydrogen atoms attached to the carbon chain than alkanesAlkenes are unsaturated hydrocarbons with C-C douple bonds

Alkynes are unsaturated hydrocarbons with C-C triple double bondsUnsaturated Hydrocarbons

*Naming Hydrocarbons There are two parts: The first represents the number of the carbon atoms: C (meth), 2C (eth), 3C (prop), 4C (but), 5C (pent), 6C (hex), 7C (hept), 8C (oct) 9C (non), 10 C () The second represents the family (Alkane, Alkene or alkyne) 1 2 3 4CH3CH2CH2CH3 butane CH2=CHCH2CH31-butene CH3CCCH3 2-butyne

Introduction Aromatic hydrocarbons are compounds contaninig benzen ring They are unsaturatedThey contain carbon to carbon double bond

Benzene Ring

Compounds that have the same molecular formula, but different structures (arrangements of the atoms) are called isomers.Naming alkanesIdentify the longest continuous chain.The locations or other groups of atoms attached to the longest chain are identified and numbered by counting from the end of the molecule which keeps the numbering system as low as possible.Hydrocarbon groups that are attached to the longest continuous chain and named using the parent name and changing the ane suffix to yl.

Molecular formula (A) describes the numbers of different kinds of atoms in a moleculeStructural formula (B): represents a two-dimensional model of how the atoms are bonded to each other Each dash represents a bonding pair of electrons.Molecular formula Structural formula

Alkenes and AlkynesAlkenes are hydrocarbons with at least one double carbon to carbon bond.To show the presence of the double bond, the ane suffix from the alkane name is changed to ene.The alkenes are unsaturated with respect to hydrogenThis means it does not have the maximum number of hydrogen atoms as it would if it were an alkane (a saturated hydrocarbon).

Naming is similar to naming alkanes except:The longest continuous chain must contain the double bond.The base name now ends in ene.The carbons are numbered so as to keep the number for the double bond as low as possible.The base name is given a number which identifies the location of the double bond.An alkyne is a hydrocarbon with at least one carbon to carbon triple bond.Naming an alkyne is similar to the alkenes, except the base name ends in yne.

Cycloalkanes and Aromatic HydrocarbonsCycloalkanes are alkanes (only carbon to carbon single bonds) which form a ring structure.An aromatic compound is one that is based on the benzene ring.A benzene ring that is attached to another compound is given the name phenyl.

*Functional groups are:a characteristic feature of organic molecules that behave in a predictable way. composed of an atom or group of atoms. groups that replace a hydrogen atom in the corresponding alkanea way to classify families of organic compounds.Functional Groups

*Alkenes and AlkynesAlkenes contain a double bond between adjacent carbon atoms.

Alkynes contain a triple bond

*Alcohols and EthersAn alcohol contains the hydroxyl (-OH) functional group.

In an ether, an oxygen atom is bonded to two carbon atoms. COC

*Aldehydes and KetonesAn aldehyde contains a carbonyl group (C=O), which is a carbon atom with a double bond to an oxygen atom.

In a ketone, the carbon of the carbonyl group is attached to two other carbon atoms.

Carboxylic Acids and EstersCarboxylic acids contain the carboxyl group, which is a carbonyl group attached to a hydroxyl group. O COHAn ester contains the carboxyl group between carbon atoms

*Amines and AmidesIn amines, the functional group is a nitrogen atom. | N

In amides, the hydroxyl group of a carboxylic acid is replaced by a nitrogen group.

*Functional GroupsCopyright 2005 by Pearson Education, Inc.Publishing as Benjamin Cummings

*Learning CheckClassify each of the following as: alcohol, ether, aldehyde, ketone, carboxylic acid, ester, amine or amide.1)CH3CH2CH2OH2) CH3OCH2CH33) CH3CH2NH2

O O 4) CH3COH 5) CH3COCH3

*Solution1)CH3CH2CH2OHalcohol2) CH3OCH2CH3 ether3) CH3CH2NH2amine

O O 4) CH3COH 5) CH3COCH3 carboxylic acid ester

Functional Groups

IntroductionHydrocarbon derivatives are formed when one or more hydrogen atoms is replaced by an element or a group of elements other than hydrogen.Halogens (F2, Cl2, Br2, I2,) can all add to a hydrocarbon to form am alkyl halide.When naming the halogen the ine ending is replaced by oFluorine becomes fluoroChlorine becomes chloroBromine becomes bromoIodine becomes iodoHydrocarbon Derivatives

Common examples of organic halides.

Alkenes can also add to each other in an addition reaction to form long chains of carbon compounds.this is called polymerizationThe atom or group of atoms that are added to the hydrocarbon are called functional groups.Functional groups usually have multiple bonds or lone pairs of electrons that make them very reactive.

AlcoholsAn alcohol has a hydrogen replaced by a hydroxyl (-OH) group.The name of the hydrocarbon that was substituted determines the name of the alcohol.The alcohol is named using the hydrocarbon name and adding the suffix ol.If methane is substituted with an OH group it becomes methanolIf a pentane group is substituted with an OH group it is pentanol.For alcohols with more than two carbon atoms we need the number the chain so as to keep the alcohol group as low as possible.

Ethers, Aldehydes, and KetonesAn ether has a general formula RORDiethyl ether for example would have the formula CH3CH2OCH2CH3An aldehyde has a carbonyl group (carbon double bonded to an oxygen) attached to a terminal carbon atomA ketone has a carbonyl group attached to an internal carbon atom.

The carbonyl group (A) is present in both aldehydes and ketones, as shown in (B). (C) The simplest example of each, with the IUPAC name above and the common name below each formula.

Organic Acids and EstersOrganic acids are those acids that are derived from living organisms, usually from metabolism, but sometimes as a defense mechanism.Long chain organic acids are known as fatty acids.These are also called carboxylic acids as they contain the carboxyl functional group (COOH) One oxygen is double bonded to the carbon and the other is bonded to the carbon and to the hydrogen both with single bonds.Esters are condensation products of carboxylic acids with the removal of water (also called a dehydration synthesis).

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