Fluorous Lewis acids and phase transfer catalysts

In 1923, G. N. Lewis proposed a generalized definition of acid-base behavior in which acids and bases are identified by their ability to accept or to donate a pair of electrons and form a coordinate covalent bond.
A coordinate covalent bond (or dative bond) occurs when one of the atoms in the bond provides both bonding electrons. For example, a coordinate covalent bond occurs when a water molecule combines with a hydrogen ion to form a hydronium ion. A coordinate covalent bond also results when...

This lesson delves into Lewis acids and bases in the context of the octet rule for electron-deficient compounds. Here, the concept is discussed, emphasizing the group 13 elements like boron or aluminium. Since group 13 elements possess three valence electrons, they form trivalent compounds with a sextet of electrons and a vacant orbital for the central atom. Consequently, these electron-deficient compounds accept electrons from other species to complete their octet in a chemical reaction. They...

Hydrolysis of acid halides is a nucleophilic acyl substitution reaction in which acid halides react with water to give carboxylic acids. The reaction occurs readily and does not require acid or a base catalyst.
As shown below, the mechanism involves a nucleophilic attack by water at the carbonyl carbon to form a tetrahedral intermediate. This is followed by the reformation of the carbon–oxygen π bond along with the departure of a halide ion. A final proton transfer step yields carboxylic acid...

Heterogeneous catalysis involves a catalyst in a different phase from the reactants. It is a process where the catalyst and the reactants are in distinct phases, typically solid and gas or liquid.Most heterogeneous catalysts are metals, metal oxides, or acids. The list includes transition metals like iron (Fe), cobalt (Co), nickel (Ni), palladium (Pd), platinum (Pt), chromium (Cr), manganese (Mn), tungsten (W), silver (Ag), and copper (Cu). These metals possess partially vacant d orbitals that...

The Fischer esterification reaction was developed by the German chemist Emil Fischer in 1895. It is a condensation reaction between carboxylic acids and alcohols in an acidic medium to give esters and water.

Carboxylic acids react with alcohols to yield esters via an acid-catalyzed condensation reaction called Fischer esterification. This is a nucleophilic acyl substitution reaction that proceeds via a tetrahedral intermediate, where a water molecule is eliminated as the leaving group.