Burgess reagent triethylammonium hydroxide inner salt

Methyl (carboxysulfamoyl)triethylammonium hydroxide, inner salt (Burgess reagent). 

Another possible method for the selective introduction of thioamide bonds into cyclic peptides is the use of oxazoles. 513-515 The oxazoles, which can be generated in serine- or threonine-containing peptides by the use of the Burgess reagent [(methoxycarbonyl-sulfamoyl)triethylammonium hydroxide inner salt) or under Mitsunobu conditions (see Section 6.8.5.2.2.2), are thionylated with hydrogen sulfide and triethylamine. A disadvantage of this method is that it is limited to serine- and/or threonine-containing peptides. 

On treatment with (carboxysulfamoyl)triethylammonium hydroxide inner salt methyl ester (Burgess reagent), the adducts of ketones yielded 1-vinylcyclopropyl selenides, but the adducts of aldehydes, e.g. 4, rearranged to cyclobut-1-enyl selenides.176... 

Lamberth, C. Burgess reagent ([methoxycarbonylsulfamoyl]triethylammonium hydroxide, inner salt) dehydrations and more. J. Prakt. Chem./Chem.-Ztg. 2000, 342, 518-522. 

In some cases the method chosen for dehydration has a decisive effect on the outcome of the reaction. Thus, the adduct of 4,4-dimethylcyclohex-2-enone underwent dehydration with (methoxycarbonylsulfamoyl)triethylammonium hydroxide, inner salt (Burgess reagent) in refluxing benzene to give 5,5-dimethyl-2-[l-(phenylsulfanyl)cyclopropyl]cyclohexa-l,3-diene (5) in 93% yield. 

When 1-phenylsulfanylcyclopropanols 66 were treated with either p-toluenesulfonic acid under anhydrous conditions or the methyl ester of (carboxysulfamoyl)triethylammonium hydroxide, inner salt (Burgess reagent) high yields of 1-phenylsulfanylcyclobutenes 67 were obtained. ... 

The Burgess reagent [(methoxyearbonylsulfamoyl)triethylammonium hydroxide inner salt], a neutral, white erystalline solid, is effieient at generating olefins from seeondary and tertiary aleohols where the first-order thermolytie Ei (during the elimination takes plaee— flie two groups leave at about the same time and bond to each other concurrently) mechanism prevails. 

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