Biochem SNR

8/3/2019 Biochem SNR

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Sherwin N. Reyes, MT, MSc, PSM, PSMAP, ISIDFACULTY FEU- Nicanor Reyes Medical Foundation

Institute of MedicineSchool of Medical Technology

Departmetn of Microbiology and Parasitology

A GLANCEwith

ORGANICCHEMISTRY


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ORGANIC CHEMISTRY


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ORGANIC CHEMISTRY

Is the chemistry that deals with carbon andits compund.


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Carbon

An element that belongs to

Period 2

Group IV of the Periodic Table of Elements


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ATOMIC STRUCTURE OFCARBON


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Electronic Configuration

Ground State:

1s2, 2s2, 2p2

Excited State: 1s2, 2s1,2px1,2py1,2pz1


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COVALENT BONDING andHYBRIDIZATION

When two hydrogen atoms approach each other, their 1s

atomic orbitals interact to form a bonding

H:H

.H

H H

H:H

H.


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SIGMA BONDING

The bonding molecular orbitals of hydrogen is anexample of a sigma bond

Strong interactions

Formed by head-on overlap of two atomic orbitals


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METHANOL

Methanol bonds areexample of covalent wherethere is an uneaqualsharing of electrons

Making oxygen moreelectronegative

Electronegative:

C= 2.5

O= 3.5

H= 2.1


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3 Types of Carbon Hybrid

sp3,sp2, and sp Sp3 results from the blending of 1 s orbital and 3p

orbitals to form 4 sp3 hybrid orbitals

Sp2 results when 1 s orbital and 2 p orbitals blend andform 3 sp2 hydrids leaving 1 of the orbitals unhydridized

Sp results from the combination of 1 s and 1 p orbitalforming 2 sp hybrid orbitals with 2 p orbitals leftunhybridized.


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Sp2

results when 1 s orbital and 2 p orbitals blend and form 3sp2 hydrids leaving 1 of the orbitals unhydridized


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Sp3

Sp3 results from the blending of 1 s orbital and 3porbitals to form 4 sp3 hybrid orbitals


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sp

results from the combination of 1 s and 1 p orbitalforming 2 sp hybrid orbitals with 2 p orbitals leftunhybridized.


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Bonds and Hybridized Centers

Sigma and Pi bonds

All bonds in organic structures are either sigma or pi bonds

All single bonds are sigma bonds

All double bonds are made up of one sigma and one pi bond

All triple bonds are made up of one sigma and two pi bonds


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Bonds and Hybridized Centers

Sp, sp2, and sp3 centers All atoms linked by a single bond are sp3 hybridized except

hydrogen

Both carbon atoms involved in the double bond of an alkene

(C=C) must be sp2 hybridized

Both the carbon and the oxygen of a carbonyl group (C=O) mustbe sp2 hybridized.

All aromatic carbons must be sp2 hybridized

Both atoms involved in a triple bond must be sp hybridized

Hydrogen uses 1s orbital for bonding and is not hybridized


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Shapes

The shape of organic molecules and functional groupswithin them is determined by the hybridization of theatoms present.

Examples:

Functional groups containing trigonal planar sp2 centers areplanar while functional groups containing sp centers are linear.

Planar functional groups aldehyde, ketone, alkene, carboxylic acid, acid chloride,acid anhydride, ester, amide, aromatic

Linear Functional groups alkyne, nitrile

Functional groups with tetrahedral carbons alcohol, ether, alkyl halide


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Reactivity

Functional groups which contain bonds are reactivesince bonds is weaker than a bond and can easilybroken.

Common functional groups which contain bonds are aromaticrings, alkenes, alkynes, aldehydes, ketones, carboxylic acids,esters, amides, acid chlorides, acid anhydrides and nitriles.


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Functional Groups


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Functional Group


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Nomenclature of Simple Alkene

Straight Chain Alkanes

# CarbonNameMolecularFormulaStructuralFormula

1 Methane CH4 CH4

2 Ethane C2H6 CH3CH3 3 Propane C3H8 CH3CH2CH3

4 Butane C4H10 CH3CH2CH2CH3

5 Pentane C5H12 CH3CH2CH2CH2CH3

6 Hexane C6H14 CH3(CH2)4CH3

7 Heptane C7H16 CH3(CH2)5CH3

8 Octane C8H18 CH3(CH2)6CH3

9 Nonane C9H20 CH3(CH2)7CH3

10 Decane C10H22 CH3(CH2)8CH3


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The IUPAC system requires first that we have names for simpleunbranched chains, as noted above, and second that we have names forsimple alkyl groups that may be attached to the chains. Examples of somecommon alkyl groups are given in the following table. Note that the "ane"suffix is replaced by "yl" in naming groups. The symbol R is used todesignate a generic (unspecified) alkyl group.

Group CH3 MethylC2H5 EthylCH3CH2CH2 Propyl(CH3)2CH sopropyl

CH3CH2CH2CH2

Butyl(CH3)2CHCH2 IsobutylCH3CH2CH(CH3) sec-Butyl(CH3)3C tert-ButylR Alkyl


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IUPAC Rules for Alkane Nomenclature

1. Find and name the longest continuous carbon chain.2. Identify and name groups attached to this chain.3. Number the chain consecutively, starting at the end

nearest a substituent group.4. Designate the location of each substituent group by

an appropriate number and name.5. Assemble the name, listing groups in alphabetical

order using the full name (e.g. cyclopropyl before

isobutyl).The prefixes di, tri, tetra etc., used to designate

several groups of the same kind, are not consideredwhen alphabetizing.


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Name the following

For the above isomers of hexane the IUPAC names are:B 2-methylpentaneC 3-methylpentaneD 2,2-dimethylbutaneE 2,3-dimethylbutane


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Alkenes and Alkynes

Alkene and alkynes are defined by addingthe suffixes ene and yne.


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Alcohols

Alcohols (or alkanols) are given the suffix -anol


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Ether and Alkyl halides

Ethers and alkyl halides are not identifiedby suffixes. Instead, these functionalgroups are considered substituent of the

main alkene chain.


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Aldehydes and Ketones

Aldehydes (alkanals) are identified by thesuffix anal. Ketones (alkalones) areidentified by the suffix anone. Aldehyde

must always be at position 1 of the mainchain and do not need to be numbered.


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Carboxylic acids and Acid chlorides

Carboxylic acids and acid chlorides areidentifiedby adding the suffix anoic acidand anoyl chloride. Both these functional

groups are always at the end of the mainchain and do not need to be numbered.


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Esters

Esters are named from the parentcarboxylic acid and alcohol. The alkanoicacid is renamed alkanoate and the alkanol

is treated as an alkyl substituent. Thecombined name is alkyl alkanoate. Theremust be a space between both parts of the

name.


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Amides

Are termed as alkanamides based on theparent carboxylic acid. If the amidenitrogen has alkyl groups, then are

considered as alkyl substituent. Thesymbol N is used to show that thesubstituents are on the nitrogen and not

some other part of alkanamide skeleton.


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Amines

Has a suffix ylamine after the root name.


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General Classification of OrganicCompounds

1. Hydrocarbons made up exclusively ofcarbon and hydrogen.

2. Hydrocarbon derivatives one of thesubtituents of carbon has been replaced by

a non carbon or non hydrogen atom.3. Biomolecules biologically active

macromolecules.


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Hydrocarbons

A. Open Chain/Aliphatic Linear

Alkanes

Alkenes

Alkynes Alkadienes

Conjugated dienes possess alternating double bonds

Cumulative dienes possess consecutive double bonds

Isolated dienes

possess double bonds separated by morethan 1 carbon atom intervals.


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Hydrocarbons

B. Cyclic possess ring structures

Aromatic benzene ring

Cycloalkanes


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Hydrocarbon derivatives

One of the subtituent of carbon has beenreplaced by a non carbon or non hydrogenatoms Alcohols

Ethers

Aldehydes

Esters

Ketones

Amines

Carboxylic acids

Halides


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Biomolecules

Biologically active macro molecules

Nucleic acids

Proteins

Carbohydrates

Lipids


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Nucleic Acid

are biological molecules essential for life, andinclude DNA (deoxyribonucleic acid)and RNA (ribonucleic acid).

Together with proteins, nucleic acids make up the most

important macromolecules; each is found in abundancein all living things, where they function in encoding,transmitting and expressing genetic information.

Nucleic acids were first discovered by FriedrichMiescher in 1871.
http://en.wikipedia.org/wiki/Moleculeshttp://en.wikipedia.org/wiki/DNAhttp://en.wikipedia.org/wiki/RNAhttp://en.wikipedia.org/wiki/Proteinhttp://en.wikipedia.org/wiki/Macromoleculehttp://en.wikipedia.org/wiki/Friedrich_Miescherhttp://en.wikipedia.org/wiki/Friedrich_Miescherhttp://en.wikipedia.org/wiki/Friedrich_Miescherhttp://en.wikipedia.org/wiki/Friedrich_Miescherhttp://en.wikipedia.org/wiki/Friedrich_Miescherhttp://en.wikipedia.org/wiki/Macromoleculehttp://en.wikipedia.org/wiki/Proteinhttp://en.wikipedia.org/wiki/RNAhttp://en.wikipedia.org/wiki/DNAhttp://en.wikipedia.org/wiki/Molecules


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Nucleic Acids

Deoxyribonucleic acid

Deoxyribonucleic acid is a nucleic acid that containsthe genetic instructions used in the development andfunctioning of all known living organisms.

The main role of DNA molecules is the long-termstorage of information and DNA is often compared toa set of blueprints, since it contains the instructionsneeded to construct other components of cells, such

as proteins and RNA molecules.


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Nucleic Acids

Ribonucleic acid Ribonucleic acid (RNA) functions in converting genetic

information from genes into the amino acid sequences ofproteins.

The three universal types of RNA include transfer RNA (tRNA),

messenger RNA (mRNA), and ribosomal RNA (rRNA). Messenger RNA acts to carry genetic sequence information

between DNA and ribosomes, directing protein synthesis.

Ribosomal RNA is a major component of the ribosome, andcatalyzes peptide bond formation.

Transfer RNA serves as the carrier molecule for amino acids tobe used in protein synthesis, and is responsible for decoding themRNA. In addition, many other classes of RNA are now known.
http://en.wikipedia.org/wiki/Messenger_RNAhttp://en.wikipedia.org/wiki/Ribosomal_RNAhttp://en.wikipedia.org/wiki/Transfer_RNAhttp://en.wikipedia.org/wiki/Noncoding_RNAhttp://en.wikipedia.org/wiki/Noncoding_RNAhttp://en.wikipedia.org/wiki/Transfer_RNAhttp://en.wikipedia.org/wiki/Ribosomal_RNAhttp://en.wikipedia.org/wiki/Messenger_RNA


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Proteins

are biochemical compounds consisting of one ormore polypeptides typically folded intoa globular orfibrous form, facilitating a biologicalfunction.

A polypeptide is a single linear polymer chainof amino acids bonded together by peptidebondsbetween the carboxyl and amino groups ofadjacent amino acid residues.

The sequence of amino acids in a protein isdefined by the sequenceof a gene, which isencoded in the genetic code.
http://en.wikipedia.org/wiki/Chemical_compoundhttp://en.wikipedia.org/wiki/Polypeptidehttp://en.wikipedia.org/wiki/Globular_proteinhttp://en.wikipedia.org/wiki/Fibrous_proteinhttp://en.wikipedia.org/wiki/Polymerhttp://en.wikipedia.org/wiki/Amino_acidhttp://en.wikipedia.org/wiki/Peptide_bondhttp://en.wikipedia.org/wiki/Peptide_bondhttp://en.wikipedia.org/wiki/Carboxylhttp://en.wikipedia.org/wiki/Aminohttp://en.wikipedia.org/wiki/Residue_(chemistry)http://en.wikipedia.org/wiki/Peptide_sequencehttp://en.wikipedia.org/wiki/DNA_sequencehttp://en.wikipedia.org/wiki/Genehttp://en.wikipedia.org/wiki/Genetic_codehttp://en.wikipedia.org/wiki/Genetic_codehttp://en.wikipedia.org/wiki/Genehttp://en.wikipedia.org/wiki/DNA_sequencehttp://en.wikipedia.org/wiki/Peptide_sequencehttp://en.wikipedia.org/wiki/Residue_(chemistry)http://en.wikipedia.org/wiki/Aminohttp://en.wikipedia.org/wiki/Carboxylhttp://en.wikipedia.org/wiki/Peptide_bondhttp://en.wikipedia.org/wiki/Peptide_bondhttp://en.wikipedia.org/wiki/Amino_acidhttp://en.wikipedia.org/wiki/Polymerhttp://en.wikipedia.org/wiki/Fibrous_proteinhttp://en.wikipedia.org/wiki/Globular_proteinhttp://en.wikipedia.org/wiki/Polypeptidehttp://en.wikipedia.org/wiki/Chemical_compound


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Carbohydrates

is an organic compound with the empiricalformula Cm(H2O)n(where mcould be different from n);that is, consists only of carbon, hydrogen, and oxygen,with a hydrogen:oxygen atom ratio of 2:1 (as inwater).

However, there are exceptions to this. One commonexample would be deoxyribose, a component of DNA,which has the empirical formula C5H10O4.

Carbohydrates can be viewed as hydrates of carbon,hence their name. Structurally however, it is more

accurate to view them as polyhydroxyaldehydes and ketones
http://en.wikipedia.org/wiki/Organic_compoundhttp://en.wikipedia.org/wiki/Carbonhttp://en.wikipedia.org/wiki/Hydrogenhttp://en.wikipedia.org/wiki/Oxygenhttp://en.wikipedia.org/wiki/Atomhttp://en.wikipedia.org/wiki/Waterhttp://en.wikipedia.org/wiki/Deoxyribosehttp://en.wikipedia.org/wiki/Hydratehttp://en.wikipedia.org/wiki/Polyhydroxyaldehydehttp://en.wikipedia.org/wiki/Polyhydroxyaldehydehttp://en.wikipedia.org/wiki/Ketonehttp://en.wikipedia.org/wiki/Ketonehttp://en.wikipedia.org/wiki/Polyhydroxyaldehydehttp://en.wikipedia.org/wiki/Polyhydroxyaldehydehttp://en.wikipedia.org/wiki/Hydratehttp://en.wikipedia.org/wiki/Deoxyribosehttp://en.wikipedia.org/wiki/Waterhttp://en.wikipedia.org/wiki/Atomhttp://en.wikipedia.org/wiki/Oxygenhttp://en.wikipedia.org/wiki/Hydrogenhttp://en.wikipedia.org/wiki/Carbonhttp://en.wikipedia.org/wiki/Organic_compound


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Carbohydrates

The carbohydrates (saccharides) are divided into fourchemicalgroupings: monosaccharides, disaccharides, oligosaccharides, and polysaccharides.

In general, the monosaccharides and disaccharides,

which are smaller (lower molecular weight)carbohydrates, are commonly referred to assugars.

The word saccharidecomes fromthe Greek word (skkharon), meaning "sugar".While the scientific nomenclature of carbohydrates is

complex, the names of the monosaccharides anddisaccharides very often end in the suffix -ose. For example, blood sugar is the

monosaccharide glucose, table sugar is thedisaccharide sucrose, and milk sugar is the

disaccharide lactose
http://en.wikipedia.org/wiki/Monosaccharidehttp://en.wikipedia.org/wiki/Disaccharidehttp://en.wikipedia.org/wiki/Oligosaccharidehttp://en.wikipedia.org/wiki/Oligosaccharidehttp://en.wikipedia.org/wiki/Polysaccharidehttp://en.wikipedia.org/wiki/Molecular_weighthttp://en.wikipedia.org/wiki/Sugarhttp://en.wikipedia.org/wiki/Greek_languagehttp://en.wikipedia.org/wiki/Sugarhttp://en.wikipedia.org/wiki/-osehttp://en.wikipedia.org/wiki/Blood_sugarhttp://en.wikipedia.org/wiki/Glucosehttp://en.wikipedia.org/wiki/Sucrosehttp://en.wikipedia.org/wiki/Lactosehttp://en.wikipedia.org/wiki/Lactosehttp://en.wikipedia.org/wiki/Sucrosehttp://en.wikipedia.org/wiki/Glucosehttp://en.wikipedia.org/wiki/Blood_sugarhttp://en.wikipedia.org/wiki/-osehttp://en.wikipedia.org/wiki/-osehttp://en.wikipedia.org/wiki/Sugarhttp://en.wikipedia.org/wiki/Greek_languagehttp://en.wikipedia.org/wiki/Sugarhttp://en.wikipedia.org/wiki/Molecular_weighthttp://en.wikipedia.org/wiki/Polysaccharidehttp://en.wikipedia.org/wiki/Oligosaccharidehttp://en.wikipedia.org/wiki/Oligosaccharidehttp://en.wikipedia.org/wiki/Disaccharidehttp://en.wikipedia.org/wiki/Monosaccharide


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Lipids

lipidis sometimes used as a synonym for fats,fats are a subgroup of lipids calledtriglycerides.

Lipids also encompass molecules such as fattyacids and their derivatives (including tri-,di-

, monoglycerides, and phospholipids), as well asother sterol-containing metabolites suchascholesterol.

Although humans and other mammals usevarious biosynthetic pathways to both breakdown and synthesize lipids, some essentiallipids cannot be made this way and must beobtained from the diet.
http://en.wikipedia.org/wiki/Fathttp://en.wikipedia.org/wiki/Triglyceridehttp://en.wikipedia.org/wiki/Fatty_acidhttp://en.wikipedia.org/wiki/Fatty_acidhttp://en.wikipedia.org/wiki/Triglyceridehttp://en.wikipedia.org/wiki/Diglyceridehttp://en.wikipedia.org/wiki/Monoglyceridehttp://en.wikipedia.org/wiki/Phospholipidhttp://en.wikipedia.org/wiki/Sterolhttp://en.wikipedia.org/wiki/Metabolitehttp://en.wikipedia.org/wiki/Cholesterolhttp://en.wikipedia.org/wiki/Metabolismhttp://en.wikipedia.org/wiki/Metabolismhttp://en.wikipedia.org/wiki/Cholesterolhttp://en.wikipedia.org/wiki/Metabolitehttp://en.wikipedia.org/wiki/Sterolhttp://en.wikipedia.org/wiki/Phospholipidhttp://en.wikipedia.org/wiki/Monoglyceridehttp://en.wikipedia.org/wiki/Diglyceridehttp://en.wikipedia.org/wiki/Diglyceridehttp://en.wikipedia.org/wiki/Triglyceridehttp://en.wikipedia.org/wiki/Triglyceridehttp://en.wikipedia.org/wiki/Fatty_acidhttp://en.wikipedia.org/wiki/Fatty_acidhttp://en.wikipedia.org/wiki/Triglyceridehttp://en.wikipedia.org/wiki/Fat


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Lipids

constitute a broad group of naturallyoccurring molecules thatinclude fats, waxes, sterols, fat-

soluble vitamins (such as vitamins A, D, E, andK), monoglycerides, diglycerides, triglycerides,phospholipids, and others.

The main biological functions of lipids include

energy storage, as structural components of cellmembranes, and as important signalingmolecules.[4]

Types of Organic Chemical
http://en.wikipedia.org/wiki/Moleculehttp://en.wikipedia.org/wiki/Fathttp://en.wikipedia.org/wiki/Waxhttp://en.wikipedia.org/wiki/Sterolhttp://en.wikipedia.org/wiki/Vitaminhttp://en.wikipedia.org/wiki/Monoglycerideshttp://en.wikipedia.org/wiki/Diglycerideshttp://en.wikipedia.org/wiki/Triglyceridehttp://en.wikipedia.org/wiki/Phospholipidshttp://en.wikipedia.org/wiki/Phospholipidshttp://en.wikipedia.org/wiki/Cell_membranehttp://en.wikipedia.org/wiki/Cell_membranehttp://en.wikipedia.org/wiki/Lipid_signalinghttp://en.wikipedia.org/wiki/Lipid_signalinghttp://en.wikipedia.org/wiki/Lipidshttp://en.wikipedia.org/wiki/Lipidshttp://en.wikipedia.org/wiki/Lipid_signalinghttp://en.wikipedia.org/wiki/Lipid_signalinghttp://en.wikipedia.org/wiki/Cell_membranehttp://en.wikipedia.org/wiki/Cell_membranehttp://en.wikipedia.org/wiki/Phospholipidshttp://en.wikipedia.org/wiki/Phospholipidshttp://en.wikipedia.org/wiki/Triglyceridehttp://en.wikipedia.org/wiki/Diglycerideshttp://en.wikipedia.org/wiki/Monoglycerideshttp://en.wikipedia.org/wiki/Vitaminhttp://en.wikipedia.org/wiki/Sterolhttp://en.wikipedia.org/wiki/Waxhttp://en.wikipedia.org/wiki/Fathttp://en.wikipedia.org/wiki/Molecule


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Types of Organic Chemical

Reactions

1. Addition this is characteristics ofunsaturated compounds and usuallyresults to distruption of multiple bonds.

- e.g. Hydration of ethene to form ethanol- Uses H2SO4 as catalyst

C=CH

H

H

H

+ H2O H-C-C-H

H H

H +

H2SO4 + H2O

H2SO4 HSO4


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Addition

In this type of reaction, the site for initiation is the doublebond. One of the H atoms of H2SO4 being anelectrophile would seek electrons from the electron richpi cloud of the double bond. As a result, a carbocation

intermediate is created.

C=CH

H

H

H

+ H2O H-C-C-H

H H

H +

H2SO4 + H2O

H2SO4 HSO4


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Addition

Because reaction intermediates are ustable, thecarbocations reacts with an OH- this time coming fromwater. The hydrogen from water then goes to the H2SO4restoring the H2SO4 molecule. Therefore the end

product is:

H-C-C-H

H H

H OH

w/ H2SO4 regenerated

H-C-C-H

H H

H OHH2O H+

HSO4H2SO4


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Elimination

This is the reverse of addition and usually results to thecreation of multiple bonds.

E.g. Dehydration of Ethanol

Also uses H2SO4 as catalyst and dehydrating agent


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Elimination

The potential site here is not only the presence of polarC-O and O-H bonds also the Lewis base characteristic ofoxygen, which possess lone pairs of electrons that canpotentially be shared or donated. This reaction begins

when one of the H of H2SO4 reacts with the OH ofethanol.

H-C-C-H

H H

H OH

H+

H2SO4

H-C-C-H

H H

H OH

H H2O


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Elimination

A water molecule is then removed and acarbocation is formed.

H-C-C-H

H H

H OH

H+

H2SO4HSO4 H2SO4


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Elimination

Because of the instability of the carbocation, one of theH of the neighboring C atom is lost and goes to HSO4 torestore the H2SO4 catalyst. Therefore, the end productis:

C=C

H

H

H

H

+ H2O w/ H2SO4 regenerated


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Substitution

This simply involves the replacement of one substituentby another.

E.g. The formation of ethanol and sodium bromide frombromoethane and sodium hydroxide.

C2H5Br+NaOH C2H5OH+NaBr


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ISOMERISM

Isomers are defined as compounds possesing the samemolecular formula but different structural formula.

is the phenomenon whereby certain compounds, withthe same molecular formula, exist in different forms

owing to their different organisations of atoms.

The concept of isomerism illustrates the fundamentalimportance of molecular structure and shape in organic

chemistry.

ISOMERISM CONCEPTUAL


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ISOMERISM CONCEPTUAL

CHART


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Structural Isomerism

Structural Isomers have different structuralformulaebecause their atoms are linked together indifferent ways.

It arises owing to:

arrangement of Carbon skeleton

e.g. The formula C4H10 represents two possiblestructural formulae, butane and methylpropane:


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position of Functional group

e.g. propan-1-ol and propan-2-ol


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different Functional groups

e.g. the molecular formula C2H60 representsboth ethanol and methoxymethane.


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Stereoisomerism

This involves no variation in the bonding arrangement ofatoms or groups, only in their orientation in space.

Stereoisomers have the same structure and bond order

but their atoms and groups of atoms are arrangeddifferently in space. They have different spatialarrangementsand their molecules arenotsuperimposable. There are Three types:

Geometric or Cis/Trans

Optical/Enantiomerism

Conformational


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Geometric or Cis/Trans

The terms cisand transare from Latin, in which cismeans "on thesame side" and transmeans "on the other side" or "across".

Involves a double bond, usually C=C, that does not allow freerotationabout the double bond (unlike a C-C single bond). They arenot superimposable.

e.g. cis-but-2-ene and trans-but-2-ene

Stereoisomers may possess quite different physical properties, such as meltingpoint, density and solubility in water (look up those of maleic acid and fumaricacid). Ring structures and other steric factors also result in geometric isomerism.


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Optical/Enantiomerism Optical isomerism

Involves an atom, usually carbon, bonded to four different atoms orgroups of atoms. They exist in pairs, in which one isomer is themirror image of the other.

e.g. butan-2-ol

These isomers are referred to as enantiomers. The central carbon atom to which four

different atoms or groups are attached, is called an asymmetrical carbon atom.Enantiomers have identical physical constants, such as melting points and boilingpoints, but are said to be optically active since they can be distinguished from eachother by their ability to rotate the plane of polarised light in opposite directions. Amixture of enantiomers in equal proportions is optically inactive, and is calleda racemic mixture. Use an organic chemistry textbook to find out more about optical

isomerism.


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STRUCTURAL EFFECTS

These structural concepts give us ideas on theelectron distribution within atom, and thus alsoits chemical behavior.

Hybridization

Hydrogen bonding

Steric Effect - the presence of bulky groups

Inductive Effect - distortion of electron cloud

Resonance pi electron delocalization

CH Hyperconjugation sigma electron delocalization


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Thank You for Listening

END OF LECTURE

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