The Chemistry of Living Things

• Organic chemistry studies carbon compounds, the foundation of life, found in living organisms and essential in biochemistry, medicine, and industries
• Carbon's ability to form multiple bonds with itself and other elements leads to a wide variety of compounds, from simple hydrocarbons to complex biological polymers

The Chemistry of Living Things

• Organic chemistry is also known as "the chemistry of life" because it studies compounds in living organisms
• Key elements in organic compounds include:
  • Carbon (C): Central to organic chemistry; forms four covalent bonds for diverse molecules
  • Hydrogen (H): Bonds with carbon to complete and stabilize molecular structures; found in almost all organic compounds
  • Oxygen (O) and Nitrogen (N): Introduce reactivity; oxygen is in alcohols, ketones, carboxylic acids; nitrogen is in amines and amino acids
  • Sulfur (S) and Phosphorus (P): Present in biomolecules; sulfur in thiols and proteins, phosphorus in nucleic acids (DNA, RNA) and energy molecules (ATP)
• Biological organic molecules are divided into four main classes:
  • Carbohydrates: Essential energy sources, (e.g., glucose, starch, cellulose)
  • Proteins: Cellular structures and biological catalysts (enzymes)
  • Lipids: Cell membrane components and energy reserves
  • Nucleic Acids: Genetic material coding hereditary information (DNA, RNA)

Carbon Bond Types

• Structures and properties are affected by atom arrangement in a molecule
• Types of bonds between carbon atoms:
  • Single Bond (C-C): Most common; allows free rotation, making structures flexible; found in alkanes (saturated hydrocarbons)
  • Double Bond (C=C): Stronger than single; limits rotation; increases chemical reactivity; found in alkenes
  • Triple Bond (C≡C): Strongest and most rigid; prevents rotation, makes molecules linear; found in alkynes
• Carbon forms various structural configurations:
  • Linear chains: Carbons are linked in continuous, unbranched structures
  • Branched chains: Some carbons form branches
  • Cyclic structures: Carbons form closed rings, like cycloalkanes and aromatic hydrocarbons
• This versatility can create compounds with diverse properties

Formulas

• Used to represent organic compounds, providing information about composition and structure
• Empirical Formula (Molecular):
  • Indicates the number of atoms of each element in a molecule without showing how they are linked (e.g., C2H6O for ethanol or dimethyl ether)
• Structural Formula:
  • Shows the arrangement of atoms and chemical bonds within the molecule, helping to understand three-dimensional arrangement (e.g., methane (CH4))
• Rational formula
  • Abbreviated notation showing atom connections without explicitly representing bonds, useful for quickly writing structures while retaining information about functional groups
  • (e.g., CH3CH2OH represents ethanol, CH3OCH3 represents dimethyl ether)

Structure and Classification of Organic Compounds

• Organic chemistry studies carbon-containing compounds with structures and properties to classify them
• Concepts explored include isomerism, and aliphatic, alicyclic and aromatic hydrocarbons

Isomerism Concept

• Isomerism is an important phenomenon with compounds having the same chemical formula but different structures
• This difference in atomic arrangement leads to diverse physical and chemical properties

What Is Isomerism

• Isomers are chemical compounds sharing the same molecular formula but with atoms arranged differently, resulting in varying chemical structures
• Isomers react differently or have different physical properties like melting/boiling points or solubility.

Types of Isomerism

• Isomerism falls into three categories: structural, geometric, and optical

Structural (or Constitutional) Isomerism

• Structural (or constitutional) Isomerism has compounds with the same molecular formula but atoms connected differently, forming different structures
• Structural isomers cannot be interchanged because they have a different order of bonds
• Chain isomers: Differ in how carbon atoms are linked, (e.g., straight chain vs. branched)
  • Butane (n-butane) has a linear four-carbon chain
  • Isobutane (2-methylpropane) has a branched chain
• Position isomers: Differ in the position of a functional group or double bond on the carbon chain, (e.g., 1-butene and 2-butene differ in double bond location)
• Functional group isomers: Compounds with same number/type of atoms but belong to different functional groups (e.g., alcohol vs. ether), resulting in varying properties.

Geometric (or cis-trans) Isomerism

• Geometric Isomerism is the same chemical formula and structure, but differ in the spatial arrangement of groups, typically in double-bonded compounds or rings preventing rotation
  • Cis: identical groups are on the same side of double bond or ring
  • Trans: identical groups are on opposite sides Geometric isomerism influences reactivity and physical properties, as seen in butene
  • Cis-butene: identical are on the same side of the double bond
  • Trans-butene: identical groups are on opposite sides

Optical Isomerism

• Optical Isomerism is when a compound has a chiral center, with a carbon atom bonded to four different groups,
• Optical isomers are enantiomers, mirror images that cannot be superimposed, like right and left hands
  • Enantiomers have identical properties except for rotating polarized light.
  • One rotates light clockwise, the other counterclockwise
• Enantiomers can have different effects in the human body, with one therapeutic and the other toxic

Why Is Isomerism Important

• Understanding how organic compounds interact with the environment and biological systems
• Spatial arrangement directly impacts chemical reactivity and physical properties
• In biology, optical isomerism determines a drug's effectiveness
• With Polymers chain structure affects mechanical and chemical properties

Hydrocarbons

• Classifications are organic compounds formed only of carbon (C) and hydrogen (H)
• This is the base of organic chemistry and subdivided based on structure
• There exist 3 main groups of hydrocarbons:

Aliphatic Hydrocarbons

• linear or branched structures

Alicyclic hydrocarbons

• cyclic structures without aromatic rings

Aromatic hydrocarbons

• cyclic structures with delocalized electron systems

Aliphatic Hydrocarbons

• Are open-chain compounds, linear or branched structures without rings
• Three Subcategories:
  • Alkanes (saturated hydrocarbons);
    • Have only single C-C bonds
    • Defined as "saturated" because each carbon is bonded to the maximum possible number of hydrogen atoms;
    • general formula CnH2n+2
    • Nonpolar, poorly soluble in water
    • Examples: methane(CH4), ethane(C2H6), and propane(C3H8)
    • Have low reactivity, but can undergo combustion and substitution reactions with halogens
  • Alkenes (unsaturated hydrocarbons with double bonds)
    • Contain one or more C=C double bonds
    • Defined as "unsaturated" because they have fewer hydrogens than alkanes
    • General formula CnH2n;
    • Double bond introduces rigidity, causing Geometric Isomerism,(cis-trans);
    • More reactive than alkanes because the double bond participates in addition reactions
    • Examples: ethene(C2H4) , propene(C3H6)
  • Alkynes (unsaturated hydrocarbons with triple bonds)
    • Contain one or more C≡C triple bonds
    • General formula CnH2n-2
    • More reactive than alkenes due to the triple bond, easily attacked in addition reactions
    • Examples: ethyne(C2H2) , propyne(C3H4)

Alicyclic Hydrocarbons

• Are similar to aliphatic but have a cyclic structure
  • Consist of cycloalkanes, which are alkanes in a closed structure (cycle)
    • Have general formula CnH2n (same as alkenes but with only single bonds)
    • less reactive than alkenes and alkynes
    • Examples: cyclopropane (C3H6), cyclobutane (C4H8) , and cyclohexane (C6H12)
  • Cycloalkenes and cycloalkynes contain double or triple bonds within the ring;
    • more reactive than cycloalkanes
    • examples: cyclopentene (C5H8) and cyclohexyne (C6H10)

Aromatic Hydrocarbons

• Cyclic compounds with delocalized electrons within the ring, providing extra stability
  • Benzene and Aromatic Compounds
    • benzene (C6H6) is well known
    • six carbon atoms arranged in a hexagonal ring with delocalized double bonds
    • electron delocalization makes benzene stable and less reactive than alkenes
    • Benzene derivatives include toluene (C6H5CH3), phenol (C6H5OH), and aniline (C6H5NH2)
• Huckel's rule:
  • Aromatic, must meet conditions:
    • Have a ring with delocalized electrons
    • Contain (4n + 2) π electrons, (where n = 0, 1, 2, 3...) Benzene has 6 π electrons
    • Be planar.
• Non aromatic: anti-aromatic/ non-aromatic molecules Gli importance degli Idrocarburi: role in diverse ambiti:
  • Energia: fuel: as methane, propane, gasoline, gasoil come from fuel. Derived from hydrocarbs Industria chimica: used for use produce solventi, vernici, farmaci.
  • Biologia essenziali for cellule membrane

Functional Groups and Classes of Compounds

• Functional groups are atom groups within organic molecules that determine chemical and physical properties
• Classes of organic compounds has a characteristic functional group influencing their reactivity and interactions.

Alcohols (-OH): Hydroxyl Compounds

• Are organic characterized by hydroxyl functional group(-OH) bonded to sp3 hydridized carbon.
• Formula has R-OH, where R represents an alkyl or aryl group

Classification of Alcohols

Alcohols are divided into 3 categories based on number of alkyl groups attached to the carbon carrying hydroxyl

Primary alcohols; alcohol bonded only one carbon. Example( Ethanal)

Alcohols secondary ; bond to the hydrixyl which has two atom bonded/Example(Isopropanol)

Alcohols tersiari ;

Carbon attached to 3 carbon atom Examples: T-butanolo used as solvent/disinfettant

Classificazioni e Caratteristiche:

• Gruppo OH.
• Thanks from the Gruppo OH: The alcool Can formulazione legami increased level Rispetto the idrocarburi simili

Solubilita

• A cortoa catena alti solubili
• Piú grandi divento meno solúbile perche piú idrofobica la catene

Chemical reagenti dell’ Alcool

• Gli alcool Puó essete diverse reaction chimica
• Combustion:: Reagisco in presenze oxygen producendo water
• Reagenti con metallico: formation Alcossidi/drogeno Gazzosa
• Ossidazione: Gli alcool can osidation a compositi in classificazione:
  • Alcool primaire: formation Acidi carbossilici
• Alcool secondari: formation Chetani alcool terziari Non ossidante

Appplication degli alchool

• Etanolo drink industry in disinfectant industry and dilutante Solvents
• Metanolo Industry combustant solvents
• Glycerol Ingrediente in cosmetici, lubrication lubricant’s

Ethers Group (R-O-R’);

Oxygenated Composites: Oxygen between alkyls/ aryls/ single links Struttura general degli etheri Formula R-O-r’re R and R can alkyls o arilici/ aromatic

Proprietá chimico-fisiche degli eteri

Influence of Atoms

Property Chimico-fisiche

• Punto di Ebbolizone baso
• Bassa forza/ debola in solobilitá
• Inert Chimica
• Molto volatile

Classificazione degli eterni

• Semplizi/simmetrici
• Misti Asimettici
• Attivitá degli eterei
  • Gli eterei sono base reattive possion essete reaction importante
  • Reazione acidi forti (HBr. Hi)-> convert in alcol genori

ammine(NH2 NHR NR2)= Composti Azotati

• derivation of amoniaco NH3 uno/do/ tutti idrogen sustituti di alchilici ó arili

Classificazione dello Ammine

• Base numori gruppo sostituente lega atómo azotato
• Ammine primary, secondary e terziarie

Geometria Molecolare:

• Le amminé sono con struttura pira

Propiate dellle Ammine

• Punto ebolazione con superiór al cani capacity di Formare a intermolecoalari intermolare Componets Sollo Soloubit in acua Forza legami rendendolo in punti ebolazione inferior the rispetto alcool in acua
• Solubitá in Acua : primaria Soloubil perche legame ha dogenó In acqua rende alto solubili Soprtatuto quando hanno catene la Solibitá alichilia

Reagibilitá delle Amine

Grazie reazioni chimiche partecipono natura basica/nucleofila Reagiscono acid forte Foramzione deili Amminio:

Esempio/ metili Aacido/ metilammonio

Alchilazione Acolazione ossidationa: amminde primaria

• possono ossidiate compisti a nitro nitroso; ammide secondarie possone

• Les applications des amine

• Importantissima for farmica Industiria/ molti faramci tengono Importante in sintetizzati polimi e solventíi

• Agente Bioligca : ammide biogeni tengono trasmettitori in sisitema nerová

Aldeide/ Cetonni

• Sono con clasici in compresivo carbonico
• Struttura é differrnte tra aldeide ed cetoni

###Differente struttura tra aldeide cedetoni

aldeideil/ GRUPPOM carbolico é posizione estremat

legato gruppo alchilico/arilo ###Propieta Chimico

Propietá chimico fisiche

• gruppo carbonio e polaizato ossigeno porta pariazle caricat a carbonia

Punti Ebolizone

• A causa Gruppo carbonico

• Le solubil alto grazie capacity Gruppo carbone a hydrohgen

• La solubila dimminuisce con la catena carboniosa

Le reagenti deller Gruppo carbonilico

• rende le aldeidi carbonili reageti per molti reagente

Addizonale Nucleofila:

Essendo Eletteroflia Puo Essere attacatíi da attaca parte de parte

• E a Reagenti Aaddizione/ esempio le addition alcoli to forma alcoxi

####### Ossidazione aldei possono ossidaté resistente. Riduzione sialaldei

Applicazioni

le cetina Sono utilizzate nella in forame/colorati/ intermediali Iin forma

Composto Acidi Carbossilici

• Comosti Organici
• Gruppo Carbossilici
• Atoms Di carbonica/legames/ gruppo: Ossilidro/ gruppo singoli
• STRUTTURIA Nomenclatura* Il carbonio Gruppo ha Ibrdazione sp2/ geomntria plantare
• Nomenclature Acido carbossilico sono Denominazione
• sostitude deminazione a Aggiungendo

Propria Chimiche Fisiche

polarità e Legami a Idrogeno

I Gruppi Acidi Carbossilici sono Gruppi Polari In grando/ Foramere Ligemi a idrogeno Sia con I inter Molecole in Qua Acqua influenzando la proprietà Fisca.

Punt/Ebolizione

Le capacita forre le games/ ha un punti ebulizone superiór che alcool atri Solibilit in Aqua : a base mas molecolari/ sono solubili in a qua a caus dei Llgemai/ idrogenó / La solitbilit ha diminue con la lunhezza deill la Catenia/carbóniosa

• Aciditá acid deubuli ma e suo ACIDITA le il superiore che la AlCool
• La ristoanza stabilazziona che la carbóxia é negativi

Reactivita

Prezenzia dell Gruppo carbossililo rende gli acidí Reative

• Forma deritavati per reacire:

Composti organici sono derivate dall' acidd con gruppii Carboni/ Con acid derivati Gli estero sono composti organico/ deriati Acidi carbossilci/ in cul: le acido acilicio/ con gruppo carbossilico Sostitudo/Da uno alchilico.

Composti Aromaticic Esterio Gruppo Carbossilicio