text: Aminosulfuranes are highly selective for the replacement of hydroxyl groups with fluoride, but in the absence of alcohol functionality, they have the ability to transform a wide array of substrates into the corresponding fluorides or acyl fluorides.  For example, ketones are converted to geminal difluorides.  However, unlike sulfur tetrafluoride, aminosulfuranes do not convert carboxylic acids into trifluoromethyl groups; the reaction halts at the acyl fluoride stage. Silyl ethers are converted to organofluorides in the presence of DAST.
  Aldehydes and ketones react with DAST to form the corresponding geminal difluorides. Fluorination of enolizable ketones gives a mixture of the difluoroalkane and vinyl fluoride. In glyme with fuming sulfuric acid, the vinyl fluoride product predominates. Electron-rich carbonyl compounds, such as esters and amides, do not react with DAST or other aminosulfuranes. 
  Epoxides may yield a variety of products depending on their structure. Generally, the products that form in highest yield are vicinal difluorides and bis(α-fluoroalkyl)ethers. However, this reaction results in low yields and is not synthetically useful.
  The polar mechanism of fluorination by DAST implies that certain substrates may suffer Wagner-Meerwein rearrangements. This process has been observed in the fluorination of pivalaldehyde, which affords a mixture of 1,2-difluoro-1,2-dimethylpropane, 1,1-difluoro-2,2-dimethylpropane, and 1-fluoro-2,2-dimethylethylene.
  Diols can undergo pinacol rearrangement under fluorination conditions.
  When sulfoxides are treated with DAST, an interesting Pummerer-type rearrangement occurs to afford α-fluoro sulfides.