TETRAMETHYLDIAMIDO PHOSPHATE DIRECTED β-LITHIATION OF A ?-EXCESSIVE HETEROCYCLE; d2-SYNTHON TO 2-SUBSTITUTED BUTENOLIDES

Article abstract of DOI:10.1016/S0040-4039(00)84267-7

The tetramethyldiamido phosphate group is described as a novel and tetracoordinated directing group in a reliable and synthetically useful β-lithiation of furan 1.Addition of 1.1 equiv. n-BuLi to 1 and quenching with electrophiles gave 2,3-disubstituted furans 3.In 98-100 percent formic acid 3 is converted to 4 in good overall yield.Thus furyltetramethyldiamido phosphate 1 is a d²-synthon for 2-furanone.