Pharmaceutical Organic Chemistry I - POC 101

Pharmaceutical Organic Chemistry I (Pharm D) - POC 101 2020/2021

• Course content covers introductions to saturated hydrocarbons (alkanes & cycloalkanes) and their stereochemistry, unsaturated hydrocarbons (alkenes & alkynes), halogenated hydrocarbons (alkyl halides, alkenyl halides & organometallic compounds), and aromatic organic chemistry (benzene, aromaticity, benzene derivatives & arenes).

Introduction to Organic Chemistry

• Organic Chemistry is the study of carbon compounds.
• Hydrocarbons are compounds containing only carbon (C) and hydrogen (H).
• A functional group is the reactive site of an organic molecule (e.g., CH₃CH₂OH, CH₃COOH, CH₃CH=CH₂).
• Functional group priority is important in IUPAC naming, determining the order of functional groups (e.g., -COOH, -COX, -CONH₂, -CHO, -CO-, -OH, -NH₂, =/=, -X, -R).

Representation of Organic Structures

• Dash structural formula: Shows all atoms and bonds explicitly.
• Condensed structural formula: Condenses the structure by omitting some bonds and implied hydrogens.
• Bond-line formula: Simplifies the structure, with implied carbons and hydrogens. Exemplified by Diethyl ether.

Electronegativity (EN)

• Electronegativity (EN) is an atom's tendency to attract electrons.
• EN increases across a period and decreases down a group on the periodic table with increasing atomic number. Values are given for various elements (H, Li, Be, B, C, N, O, F, Na, Cl, K, Br, I).

Types of Chemical Bonds

• Ionic Bonds: ΔEN > 2. Example: Sodium Chloride (NaCl).
• Covalent Polar Bonds: 2 > ΔEN > 0.5. Example: Methyl Chloride (CH₃Cl) and Methyl Lithium (CH₃Li).
• Covalent Non-Polar Bonds: ΔEN = 0 to 0.5. Example: Bromine (Br₂.) and Ethane (CH₃CH₃).

Attractive Forces Between Atoms in Organic Molecules

• Dipole-Dipole Interactions: Attractive forces between polar molecules (e.g., Methyl Chloride).
• Hydrogen Bonds: Strong dipole-dipole interactions involving hydrogen bonded to N, O, or F (e.g., Methanal, salicylic acid).
• London Forces (Dispersion Forces): Weak attractive forces between all molecules, increasing with increasing size or polarizability(e.g., Halogens).

Electron Effects of Substituents

• Inductive Effect (I effect): Electron displacement through sigma bonds. Electron-withdrawing groups (-I) have higher EN than carbon, while electron-donating groups (+I) have less.
• Mesomeric Effect (M effect): Electron delocalization in conjugated systems. Electron-withdrawing (-M) or electron-donating (+M) substituents conjugated with the molecule.

Types of Bond Cleavage

• Heterolytic Cleavage: Bond breaks, one atom retains both bonding electrons (e.g. CH₃Cl).
• Homolytic Cleavage: Bond breaks, each atom retains one bonding electron(e.g CI-CI).

Carbons Containing Intermediates

• Carbocation: A positively charged carbon intermediate (3° > 2° > 1° > CH₃).
• Carbanion: A negatively charged carbon intermediate (CH₃ < 1° < 2° < 3°).
• Free radicals: Unstable intermediates with an unpaired electron.

Types of Chemical Reagents

• Electrophiles (E+): Electron-seeking species (e.g., H+, X+, NO₂⁺, AlCl₃)
• Nucleophiles (Nu⁻): Electron-rich species that seek positive charge (e.g., OH⁻, X⁻, CN⁻, H₂O, ROH)

Types of Chemical Reactions

• Substitution Reactions (SN, SE, Free Radical): One atom or group replaces another.
• Addition Reactions (Nucleophilic, Electrophilic, Free Radical): Reactants add across a multiple bond.
• Elimination Reactions (a-, β-, γ-): Removal of atoms or groups, forming a multiple bond.

This quiz tests your knowledge on the fundamentals of Pharmaceutical Organic Chemistry, including saturated and unsaturated hydrocarbons, halogenated hydrocarbons, and aromatic organic chemistry. It will cover essential concepts such as functional groups, IUPAC naming priorities, and structures of organic compounds.