HFIP-Catalyzed Difluoroalkylation of Propargylic Alcohols to Access Tetrasubstituted Difluoroalkyl Allenes

A hexafluoroisopropanol (HFIP)-catalyzed difluoroalkylation of propargylic alcohols with difluoroenoxysilanes to access structurally diverse tetrasubstituted difluoroalkyl allenes has been developed. This convenient procedure enables the rapid construction of highly functionalized multisubstituted fluorinated allenes in a mild and straightforward way. Furthermore, the synthetic potential of this methodology has been demonstrated by the facile synthesis of various structurally interesting fluorine-containing molecules such as gem-difluorosubstituted dihydropyran, tetrasubstituted CF2H-allene, and multisubstituted fluorinated cyclopentanone derivatives.

Automated summary

A new HFIP-catalyzed difluoroalkylation reaction has been developed for the synthesis of structurally diverse tetrasubstituted difluoroalkyl allenes from propargylic alcohols and difluoroenoxysilanes. This method allows for the rapid construction of highly functionalized multisubstituted fluorinated allenes and the synthesis of various structurally interesting fluorine-containing molecules.