Claisen

Claisen may refer to:


 * Rainer Ludwig Claisen, a German chemist
 * Claisen rearrangement, a reaction of a allyl vinyl ether to a γ,δ-unsaturated carbonyl
 * Claisen condensation, a reaction between esters and carbonyl compounds in the presence of a strong base
 * Ireland–Claisen rearrangement, a chemical reaction of an allylic ester with strong base
 * Claisen isatin synthesis