Chemistry 'beyond the molecule': non-covalent assembly (hydrogen bonding, π-stacking, metal-ligand, hydrophobic) into crown ethers, cryptands, cyclodextrins, self-assembled cages, rotaxanes/catenanes, metal-organic frameworks (MOFs). …
supramolecular-chemistry
Host–guest complex
Non-covalent inclusion complex in which a molecular host (crown ether, cryptand, cyclodextrin, cucurbituril, pillar[n]arene, …) binds a…
Molecular self-assembly
Spontaneous organisation of molecular components into ordered aggregates through non-covalent interactions, driven by free-energy…
Crown ether
Cyclic polyether with the general formula (–CH₂CH₂O–)_n, named [n]-crown-m where n is the ring size and m the number of oxygens. …
Rotaxane
Mechanically-interlocked molecular architecture consisting of a macrocyclic ring threaded onto a linear dumbbell-shaped axle that is too…
Metal–organic framework (MOF)
Crystalline porous solid built from metal-ion (or cluster) nodes connected by polytopic organic linkers via coordination bonds. …
Cucurbiturils (CB[n])
Barrel-shaped hosts from glycoluril+formaldehyde; ultra-high affinity (Ka>10¹² M⁻¹) for cations with hydrophobic interiors. Drug delivery,…
Catenanes & mechanical bonds
Interlocked rings without covalent linkage. Template synthesis (Sauvage Cu(I)). Molecular machines. Stoddart/Sauvage/Feringa Nobel 2016.
Molecular machines
Mechanically interlocked architectures + switches performing directed motion. Feringa's light-driven motor, Stoddart's molecular shuttle,…
Self-assembly principles
Spontaneous organization via non-covalent interactions (H-bond, π-π, hydrophobic, metal coordination). Enables bottom-up nanostructures:…
Metal-organic cages
Discrete polyhedra (M₂L₃, M₄L₆, M₁₂L₂₄) self-assembled from metal nodes + organic ligands. Guest binding, catalysis in confined space.…
Host-guest binding constants
K_a measured by NMR, ITC, UV-vis; Benesi-Hildebrand; thermodynamics reveal enthalpy vs entropy contributions.
Template synthesis of macrocycles
Metal ion templates rearrange ligands into macrocycles; crown ethers (18-crown-6); rotaxanes assembled by threading.
π-π stacking (parallel, T-shaped, offset)
Quadrupole/dispersion for benzene dimer ~2 kcal/mol; aromatic stacking in DNA, proteins; face-face vs edge-face.
Cation-π interactions
K⁺, ammonium, guanidinium binding aromatic π systems; 5-15 kcal/mol; acetylcholine binding, nicotinic receptors.
Anion-π interactions
Anions bind π-acidic aromatics (perfluorobenzene, triazines); reverse to cation-π; synthetic anion receptors.
Hydrogen-bonded organic frameworks (HOFs)
Purely H-bond porous networks; softer than MOFs; reconstruction on activation; carboxylic acids, DAT (diaminotriazine).
DNA molecular recognition (base pairing)
Watson-Crick (AT 2 H-bonds, GC 3) + π-stacking; triplexes, quadruplexes; sensors, therapeutics via aptamers.
Dissipative (out-of-equilibrium) self-assembly
Chemical fuel drives non-equilibrium structures; ATP in cytoskeleton; fuel-consuming materials with autonomous lifetimes.