Cross aldol condensation occurs when two different aldehydes or ketones react. If both have α-hydrogen atoms, it yields a mixture of four products. The aldol reaction of ethanal and propanal illustrates this when carried out in a mixture.

Aldol and ketol products formed in the Aldol reaction readily lose water to form α, β-unsaturated carbonyl compounds, and this reaction is known as Aldol condensation.

The Aldol reaction involves aldehydes and ketones with at least one α-hydrogen reacting in the presence of dilute alkali to form β-hydroxy aldehydes or β-hydroxy ketones. It is catalyzed by dilute alkali.

Aldehydes are easily oxidized to carboxylic acids by various oxidizing agents, including nitric acid, potassium permanganate, Tollens’ reagent, and Fehlings’ reagent. Ketones, on the other hand, undergo carbon-carbon bond cleavage to form a mixture of carboxylic acids under vigorous oxidation ...

Reduction of the carbonyl group to CH₂ occurs with zinc-amalgam and concentrated hydrochloric acid (Clemmensen reduction) or hydrazine followed by heating with sodium or potassium hydroxide in ethylene glycol (Wolff-Kishner reduction).

Aldehydes are reduced to primary alcohols, and ketones to secondary alcohols, using sodium borohydride (NaBH₄), lithium aluminium hydride (LiAlH₄), or catalytic hydrogenation.

Aldehydes are more reactive due to both steric and electronic reasons. Sterically, the hindered approach of nucleophile to the carbonyl carbon is less in aldehydes. Electronically, aldehydes are more reactive because two alkyl groups in ketones reduce the electrophilicity of ...

Aldehydes and ketones are commonly prepared by the oxidation of primary and secondary alcohols, respectively.

Carbonyl compounds have a planar structure with a π-bond, leading to substantial dipole moments. The high polarity is explained by resonance, involving neutral (A) and dipolar (B) structures, contributing to the overall dipole moment of carbonyl compounds.

The double bond is polarized due to the higher electronegativity of oxygen. The carbonyl carbon acts as an electrophilic (Lewis acid), and the carbonyl oxygen serves as a nucleophilic (Lewis base) center.