Direct oxidation of N-ynylsulfonamides into N-sulfonyloxoacetamides with DMSO as a nucleophilic oxidant

Abstract

Microwave-assisted direct oxidation of N-arylethynylsulfonamides with DMSO as a nucleophilic oxidant and solvent affords N-sulfonyl-2-aryloxoacetamides without any other additional electrophilic activators or oxidants.

Stability of Phenyl-Modified Triphenylphosphonium Conjugates and Interactions with DTPA

“…In a set of parallel studies to the hydrolysis studies above, we had set out to test for the potential role of metals contributing to an oxidative mechanism of CF 3 -TPP + -DC degradation. Because DMSO plays a role in some oxidation reactions, and metals often contribute to redox reactivity, we set out to test for these interactions by using metal chelators to sequester metals in CF 3 -TPP + -DC solutions. , Metal chelators DTPA, EDTA, and Chelex100 were used to sequester multivalent cations that are commonly involved in redox chemistry. First, EDTA was added to 1:1 DMSO:Tris buffer at pH 8.3 to give EDTA:CF 3 -TPP + -DC at a 1:1 molar ratio.…”

“…TPP + conjugates undergo several known reactions, including hydrolysis under strongly basic conditions, to give the phosphine oxide product . There are also several known reactions in organic chemistry where DMSO acts as a nucleophile in oxidation chemistry. , As such, we set out to further investigate if DMSO and/or pH was playing a role in the potential degradation of CF 3 -TPP + conjugates specifically and to evaluate the stability of different xTPP + groups more broadly in general.…”