A NOVEL METHOD FOR THE PREPARATION OF FLUOROARYL-SUBSTITUTED AND FLUOROALKYL-SUBSTITUTED BIS-PHOSPHONIC AND TRIS-PHOSPHONIC ACIDS

The formation of various aromatic fluorinated vinylphosphonates, gemin al and vicinal bisphosphonates and trisphosphonates by the Wittig-Horn er-Emmons reaction and Michael addition is presented. The regiospecifi c direction of Michael addition under basic catalysis is largely depen dent on the substitution pattern of the vinylphosphonates. The pentafl uorophenyl-substituted vinylphosphonate 8d and diethyl phosphite react to yield the novel. trisphosphonate 5. This reaction sequence substit utes the para-fluorine atom of the C6F5 unit by nucleophilic substitut ion while a simultaneous nucleophilic addition of the phosphonate grou p to the vinylic double bond takes place. Explicit NMR studies are des cribed.