Atom-economic thiophosphoroselenenylations of C–H acid esters and amides

Three improved thiophosphoroselenenylation procedures of CH-acids, including derivatives malonic and acetyl-, phosphono-, 4-nitrophenyl- 3-pyridylacetic acids, have been described compared to previously reported thiophosphoroselenylation diethyl malonate using bis(disopropoxyphosphinothioyl)diselenide alone or with the aid methyl iodide. The use iodine makes it possible utilize both equivalents selenenylating agent. work well for majority nucleophiles in a pKa range between more acidic malononitrile Meldrum acid less phenylacetates. reaction carried out on boiling rectified ethanol yields selenoacetate, which cannot be obtained by direct phosphoroselenenylation. Crystal structure one selenomalonamides confirms stabilization effects carbonyl oxygens selenium atom. P-Se bond splitting, TBAF 3-molar excess presence alkylating agent respective C,Se-dialkyl derivatives.