Development of an innovative two-step synthesis of α,α-difluorophosphinates and α,α-difluorophosphinothioates

Atwo-step rynthesis towards difluorophosphinaner (RCFYP(O)(OE)CHR) and wurdifluorophosphinothioates (RCFP(S)(OECHR) reported. These potential isosteres of phosphoric acid diesterz were prepared thanks to a radical addition step off-centered radicals derived from O-ethyl-H-methylphosphinate (HP(O)(OE)CH3) or O ethyl-H-methylphosphinothioate (HP(S)(OE)CH2) onto gem-difluoroolefins. The resultant O-ethylmethyl-a,a-difluorophosphinate (RCFP(O)(OE)CH,) and O-ethylmethyl-za-difluorophosphinothioates (RCF-P(S) (OEt)CH3) were exploited in a C-alkylation step with various electrophiles (eg. lodo-alkane, epoxide, aldehyde) to deliver the targeted products. During this study, it was also found that sodium H-methylphosphinate salt (NaHP(O)(O)CH3y) could also be used as a valuable precursor of P-centered radical.