Burgess dehydration reaction

The mechanism involves a stereospecific syn-elimination via ion-pair formation from the intermediate sulfamate ester (comparable to the Chugaev elimination of xanthate esters). Kinetic and spectroscopical data are consistent with an initial rate-limiting formation of an ion-pair followed by a fast c s- 3-proton transfer to the departing anion. 

During the first total synthesis of taxol , R. Holton and co-workers installed an exo-methylene group on the C ring in order to set the stage for the D ring (oxetane) formation. The Burgess dehydration reaction was applied to a complex tricyclic tertiary alcohol intermediate (ABC rings) and the desired exocyclic alkene was isolated in 63% yield. 

In the laboratory of A.I. Meyers, the first enantioselective total synthesis of the streptogramin antibiotic (-)-madumycin II was achieved. The natural product contains an oxazole moiety, which may be considered a masked dehydropeptide. The oxazole moiety was introduced in two steps by the Burgess cyciodehydration reaction followed by oxidation of the resulting oxazoline to the corresponding oxazole. 

Mehta and co-workers unexpectedly encountered a novel transannular Cannizzaro reaction when 1,4-bishomo-6-seco[7]prismane dialdehyde derivative was subjected to basic conditions to yield a novel octacyclic lactone. The transannular Cannizzaro reaction is the result of the proximity of the two reacting aldehyde groups induced by the rigid caged structure. 

Rebek et al. synthesized novel dibenzoheptalene bislactones via a double intramolecular Cannizzaro reaction for condensation polymerization and remote catalysis studies. These bislactones are chiral, atropisomeric molecules. 

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Related reactions Burgess dehydration, Cope elimination, Hofmann elimination ... 

Burgess reagent is commonly known for dehydration reactions but has also recently been shown to act as an oxidizer. The conversion of benzoin to benzil in good... 

Holsworth, D. D. The Burgess Dehydrating Reagent. In Name Reactions for Functional Group Transformations Li, J. J., Corey, E. J., Eds. Wiley Sons Hoboken, NJ, 2007 pp 189-206. (Review). 

Acidic reagents seem to offer milder conditions. Dehydration reactions forming cyanides can be performed with phosgene [1049-1052], diphosgene [1053-1055], triphosgene [1056], phenyl chloroformate [1057], oxalyl chloride [1058, 1059], tri-chloroacetyl chloride [1060-1062], acetic anhydride [1063-1074], TFAA [1075-1082], phosphorus oxides [1083-1088], phosphorus oxychloride [1089-1098], phosphorus pentachloride [1099], triphenylphosphine/haloalkanes [1100-1103], thionyl chloride [1104-1118], p-tosyl chloride [1119-1124], triflic anhydride [1125-1127], chlorosulfonyl isocyanate [1128], the Burgess reagent [1129], phenyl chloro-thionoformate [1130], cyanuric chloride [1131-1134], carbodiimides [1135, 1136], CDC [1137], PyBOP [1138], AlCU/Nal [1139], and acetonitrile/aldehyde [1140], and by pyrolysis [1141]. 

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