Aromatic Compounds Course

Lesson 1 • Physical Properties of Aromatic Compounds

Examines melting points, boiling points, solubility, and spectroscopic signatures of aromatic compounds. Links delocalisation to measurable physical behaviour.

Lesson 2 • Hückel's Rule and Aromaticity

Applies the 4n+2 pi electron rule to classify aromatic, antiaromatic, and nonaromatic systems. Provides the diagnostic tool used throughout the course.

Lesson 3 • Bonding in Benzene

Explains sigma framework, pi electron delocalisation, and resonance structures. Connects molecular orbital theory to observed bond length uniformity.

Lesson 4 • Nomenclature of Benzene Derivatives

Covers systematic and common naming of mono- and disubstituted benzenes. Accurate naming is prerequisite for all subsequent reaction discussions.

Lesson 1 • Directing Effects and Reactivity

Classifies substituents as ortho/para or meta directors and activators or deactivators. Predicts regioselectivity in polysubstituted benzene reactions.

Lesson 2 • Friedel-Crafts Alkylation and Acylation

Compares carbocation-based alkylation with acylium-based acylation, including limitations of each. Acylation's clean regioselectivity is contrasted with alkylation's rearrangement issues.

Lesson 3 • General EAS Mechanism

Details the two-step addition-elimination pathway and the arenium ion intermediate. Establishes the mechanistic template applied to every EAS reaction type.

Lesson 4 • Halogenation of Benzene

Covers Lewis acid-catalysed chlorination and bromination mechanisms and conditions. Introduces the role of catalysts in activating molecular halogens.

Lesson 1 • Requirements for Nucleophilic Attack

Identifies electron-withdrawing substituents and leaving group position as prerequisites for nucleophilic aromatic substitution. Contrasts reactivity with EAS requirements.

Lesson 2 • Synthetic Applications of NAS

Applies nucleophilic aromatic substitution to prepare phenols, anilines, and aryl ethers. Connects mechanism to practical multi-step synthesis planning.

Lesson 3 • Elimination-Addition via Benzyne

Covers benzyne intermediate formation under strongly basic conditions and its symmetrical addition. Explains scrambled product distribution as diagnostic evidence.

Lesson 1 • Six-Membered Nitrogen Heterocycles

Covers pyridine, pyrimidine, and pyrazine aromaticity, basicity, and EAS/NAS reactivity. Lone pair participation in aromaticity is distinguished from basicity.

Lesson 2 • Reactivity Comparisons Across Ring Systems

Synthesises reactivity trends across all ring systems covered, enabling rational substrate selection. Prepares learners for multi-ring synthesis in later chapters.

Lesson 3 • Fused Polycyclic Aromatic Hydrocarbons

Examines naphthalene, anthracene, and phenanthrene structures, stability, and reactivity patterns. Introduces peri interactions and bay region chemistry.

Lesson 4 • Five-Membered Nitrogen Heterocycles

Analyses pyrrole, imidazole, and indole aromaticity where the nitrogen lone pair contributes to the pi system. Explains reduced basicity relative to pyridine.

Lesson 1 • Oxidation of Alkylbenzene Side Chains

Describes permanganate and chromium-based oxidation of alkyl side chains to carboxylic acids. Explains why a benzylic hydrogen is required for oxidation to proceed.

Lesson 2 • Benzylic Position Reactivity

Explains benzylic radical and carbocation stabilization through resonance with the ring. Establishes why benzylic positions are uniquely reactive compared to other C-H bonds.

Lesson 3 • Benzylic Halogenation

Covers NBS-mediated radical bromination and selectivity at the benzylic position. Contrasts ring halogenation conditions with side-chain halogenation conditions.

Lesson 4 • Reduction of Aromatic Compounds

Covers Birch reduction conditions, regiochemistry, and catalytic hydrogenation of aromatic rings. Distinguishes partial from complete ring reduction outcomes.

Lesson 1 • Integrated Spectral Problem Solving

Combines NMR, IR, MS, and UV-Vis data to solve unknown aromatic structure problems. Develops systematic spectral interpretation workflow used in research and industry.

Lesson 2 • Mass Spectrometry of Aromatic Compounds

Covers molecular ion stability, tropylium cation formation, and characteristic fragmentation of benzyl systems. Enables molecular weight and structural determination.

Lesson 3 • UV-Vis Spectroscopy and Conjugation

Relates pi to pi* and n to pi* transitions to aromatic structure and substituent effects. Bathochromic and hypsochromic shifts are connected to electron density changes.

Lesson 4 • Infrared Spectroscopy of Aromatics

Identifies C-H stretch, ring C=C stretch, and out-of-plane bending bands diagnostic for aromatic compounds. Links bending patterns to substitution type.

Lesson 1 • Diazonium Salt Chemistry

Covers diazotisation of anilines and Sandmeyer reactions to install halogens, nitriles, and hydroxyl groups. Diazonium salts serve as versatile synthetic intermediates.

Lesson 2 • Retrosynthetic Analysis for Aromatics

Introduces retrosynthetic disconnection strategies specific to aromatic targets. Learners work backward from target to available starting materials using aromatic logic.

Lesson 3 • Directing Group Strategy

Uses activating and deactivating groups strategically to control polysubstitution regiochemistry. Temporary blocking groups and sequential substitution order are planned.

Lesson 4 • Cross-Coupling Reactions Overview

Introduces palladium-catalysed Suzuki, Heck, and Negishi couplings as modern aromatic bond-forming tools. Highlights advantages over classical EAS for complex targets.

Lesson 1 • Aromatic Compounds in Materials Science

Surveys graphene, carbon nanotubes, and conjugated polymers as extended aromatic systems. Links molecular aromaticity principles to macroscopic electronic properties.

Lesson 2 • Computational Approaches to Aromaticity

Introduces nucleus-independent chemical shift (NICS), aromatic stabilisation energy, and electron delocalisation indices. Connects computational metrics to experimental observations.

Lesson 3 • Non-Benzenoid Aromatic Compounds

Examines azulene, tropylium, cyclopentadienyl anion, and other non-six-membered aromatic systems. Applies Hückel's rule to confirm aromaticity in unusual ring sizes.

Lesson 4 • Superelectrophilic Aromatic Reactions

Covers doubly activated electrophiles in superacid media and their enhanced reactivity toward deactivated arenes. Extends EAS scope beyond classical conditions.