Metal Hydride Reduction with NaBH₄ and LiAlH₄ converts carbonyls to alcohols, widely used in organic and medicinal chemistry. Overview: Metal hydrides like sodium borohydride (NaBH₄) and lithium aluminium hydride (LiAlH₄) are used to reduce carbonyl compounds (aldehydes, ketones, esters, carboxylic acids, etc.) to alcohols. Sodium Borohydride (NaBH₄) Structure: Na⁺[BH₄]⁻ (a tetrahedral borohydride ion) Solubility & … Read more
This article explains about Oppenauer Oxidation oxidizes secondary alcohols to ketones using aluminium alkoxide and ketone acceptors. Overview of Oppenauer Oxidation: Oppenauer oxidation is a mild, selective oxidation method used to convert secondary alcohols into ketones (and sometimes primary alcohols into aldehydes) under non-aqueous, basic conditions. Reagents: Aluminum isopropoxide (Al(O-iPr)₃) – catalyst Excess ketone (commonly … Read more
This article explains about Wolff-Kishner Reduction converts aldehydes and ketones to hydrocarbons under strong base and heat. Type: Strong base reduction Purpose of Wolff-Kishner Reduction: Converts aldehydes and ketones to alkanes, like the Clemmensen reduction. Basic conditions, so suitable for acid-sensitive compounds. Reagents: Hydrazine (NH₂NH₂) Strong base (e.g., KOH) Heat Often done in high-boiling solvents … Read more
Birch Reduction reduces aromatic rings to 1,4-dihydro derivatives using sodium and liquid ammonia in synthesis. Purpose of Birch Reduction: Reduces aromatic rings (like benzene) to non-conjugated cyclohexadienes. Partial reduction – breaks aromaticity but doesn’t fully saturate the ring. Reagents: Alkali metal (Na, Li, or K) in liquid ammonia (NH₃) Proton source (like ethanol or tert-butanol) … Read more
Clemmensen Reduction transforms carbonyl compounds into hydrocarbons using Zn–Hg and HCl in organic synthesis. Type: Metal-acid reduction Purpose of Clemmensen Reduction: Reduces aldehydes and ketones to alkanes. Used especially for carbonyl groups adjacent to aromatic rings (aryl ketones). Reagents of Clemmensen Reduction: Zinc amalgam (Zn(Hg)) Concentrated hydrochloric acid (HCl) Reaction is acidic Mechanism (Simplified Concept): … Read more
Kinetic properties of Colloids are related to the movement of colloidal particles due to thermal or external forces. Kinetic Properties of Colloids explain particle stability, transport, and dynamic interactions. These motions contribute to the stability and behavior of colloidal systems. 1. Brownian Motion Definition: The random, zig-zag motion of colloidal particles due to continuous collision … Read more
Interfacial Properties of Suspended Particles are key in drug formulation, emulsions, and colloidal systems. It influences, aggregation, and dispersion in suspensions. At the interface between suspended particles and the surrounding liquid, several key properties affect the behavior and stability of the suspension: Interfacial Tension Exists between the solid particle surface and the liquid. Higher tension … Read more
Definition of Coarse Dispersion: A coarse dispersion is a type of dispersed system where the dispersed phase (particles) is relatively large in size (usually greater than 1 µm) and is distributed throughout a continuous phase (usually a liquid). Examples: Suspensions and emulsions. Contrast with: Colloidal dispersions (1 nm – 1 µm) True solutions (molecular size) … Read more
Definition of Suspensions: A suspension is a heterogeneous system in which insoluble solid particles (dispersed phase) are suspended in a liquid medium (dispersion medium). Applications in Pharmaceutics: Used to administer insoluble drugs orally, topically, or parenterally Examples: Antacids (e.g., aluminum hydroxide), antibiotics (e.g., amoxicillin suspension) Desirable Properties of Suspensions: Uniform particle size Stability (no rapid … Read more
Elastic Modulus (Young’s Modulus) helps assess strength in engineering and material science. Elastic Modulus (Young’s Modulus) measures material stiffness, showing stress–strain relationship. Definition: The ratio of stress to strain in the elastic region of the stress-strain curve. Measured in Pascals (Pa or N/m²). High E = stiff material (resists elastic deformation). Low E = more … Read more
