Novel nucleosides with vinyl fluoride or vinyl bromide moiety as open-chain analogs of neplanocin A

Synthesis of fluorinated and nonfluorinated sugar alkenylphosphonates via highly stereoselective Horner-Wadsworth-Emmons olefination

New fluorinated and nonfluorinated sugar alkenylphosphonates were obtained. In all cases 1,2;5,6-di-O-isopropylidene-α-d-glucofuranose was used as the starting material. The synthesis of alkenylphosphonates was based on Horner-Wadsworth-Emmons olefination. The process led to products with E-stereochemistry exclusively or predominately.

Selective preparation of tetrasubstituted fluoroalkenes by fluorine-directed oxetane ring-opening reactions

The selective ring-opening reaction of fluoroalkylidene-oxetanes was directed by the presence of the fluorine atom, enabling a two-step access to tetrasubstituted fluoroalkenes with excellent geometry control. Despite its small van der Waals radii electronic, rather than steric influences of the fluorine atom governed the ring-opening reaction with bromide ions, even in the presence of bulky substituents.