Darzens synthesis, of tetralin derivatives

Cyclization of 2-benzylpent-4-enoic acid (a-benzyl-a-allylacetic acid) and related compounds 1 to corresponding 1,2,3,4-tetrahydronaphthalene (tetralin) derivatives 2, catalyzed by a strong acid, has been called Darzens synthesis of tetralin derivatives. The reaction formally falls into the category of a cycloisomerization reaction of alkenyl-substituted arenes. 

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