The Thio-Claisen Rearrangement of Allylic Phenyl Sulfides

The Claisen Rearrangement

Nucleophilic ortho-Allylation of Pyrroles and Pyrazoles: An Accelerated Pummerer/Thio-Claisen Rearrangement Sequence

Arylsulfinyl groups direct the metal-free, regiospecific, nucleophilic ortho-allylation of pyrroles and pyrazoles. Mechanistic studies support the intermediacy of allylsulfonium salts that undergo facile thio-Claisen rearrangement onto the heterocyclic ring, giving products of coupling. The strategy has been adapted to allow regiospecific propargylation of the heterocyclic substrates.

Synthesis of nearly enantiopure allylic amines by aza-Claisen rearrangement of Z-configured allylic trifluoroacetimidates catalyzed by highly active ferrocenylbispalladacycles.

The development of the first highly active enantioselective catalyst for the aza-Claisen rearrangement of Z-configured allylic trifluoroacetimidates generating valuable almost enantiopure protected allylic amines is described. Usually Z-configured allylic imidates react significantly slower than their E-configured counterparts, but in the present study the opposite effect was observed. Z-Config...

A quantitative structure-reactivity relationship in decarboxylative Claisen rearrangement reactions of allylic tosylmalonate esters.

First-order rate constants have been determined for the decarboxylative Claisen rearrangement reactions at 293 K of substituted methyl (E)-3-phenyl-2-propenyl 2-tosylmalonate esters, which show a linear free-energy relationship indicative of the development of positive charge on the benzylic position in the sigmatropic rearrangement transition-state.

Microwave accelerated aza-Claisen rearrangement.

A study of microwave-induced and standard thermal Overman rearrangement of selected allylic trichloroacetimidates 1a-1f, 6-8 to the corresponding acetamides 2a-2f, 9-11 is reported. The microwave-assisted rearrangement of trifluoroacetimidate 13 is also described. Using this methodology, an efficient access to versatile allylic trihaloacetamides building synthons was established.