α-Mono-and α, α-disubstituted α-phosphoryl radicals 9 were generated from the easy accessible α-phosphoryl Sulfides 4, 5 and α-phosphoryl selenides 11, 12 and reacted with the electron rich alkenes 6 under the reductive (n-Bu3SnH/AIBN) conditions to give the functionalized phosphonates 7 in 32÷ 68% yield. Two fragmentation processes of the phosphonate α-alkoxy alkyl radicals are also described.