Olefination Smiles’ rearrangement

Plesniak K, Zarecki A, Wicha J (2007) The Smiles Rearrangement and the Julia-Kocienski Olefination Reaction. 275 163-250 Polito M, see Braga D (2005) 254 71-94 Poulin-Kerstien AT, see Dervan PB (2005) 253 1-31... 

The Smiles Rearrangement and the Julia-Kocienski Olefination Reaction... 

To the best of our knowledge, the first indication that the Smiles rearrangement could be applied to olefination reactions emerged from the work of Hirai and coworkers [77] in 1972. These authors reported that anion generated from the thiazole-2-thiol derivatives 161 (R = H or Ph) (Scheme 52) and n-butyllithium (when R = H, two equivalents were used) reacted with ben-zaldehyde to provide, after chromatography, thiirane 162 and 1,3-thiazoHdin-2-one. Distillation of the thiirane gave the respective olefin 163 (which was also detected in the crude product). The authors realized that the reaction occurred through a spiro-bicyclic intermediate. 

Bis-(trifluoromethyl)-phenyl plays the role of migrating ring in the Smiles rearrangement in the Najera and co-workers [106,107] modification of the olefination reaction. Judka and Makosza (Judka and Makosza, 2006, personal commimication) have shown that pentachlorophenyl and some very simple phenyl derivatives may be conveniently used in the olefination reactions imder mild conditions. Indubitably, several other aromatic and hete-rocycHc systems will be estabhshed as the templates in the direct olefination reaction, allowing for convenient choice of experimental conditions and stereochemical bias. 

Studies by Juba and by Kocienski have shown that the nature of the suhbne may exert a decisive effect on the efficiency of the olefination reaction. Diversification of the migrating rings in the Smiles rearrangement could be benefactions for extending the scope of appHcation of the reaction. 

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