Synthesis of polysubstituted N-H pyrroles from vinyl azides and 1,3-dicarbonyl compounds.
Two synthetic methods for tetra- and trisubstituted N-H pyrroles are presented: (i) the thermal pyrrole formation by the reaction of vinyl azides with 1,3-dicarbonyl compounds via the 1,2-addition of 1,3-dicarbonyl compounds to 2H-azirine intermediates generated in situ from vinyl azides; (ii) the Cu(II)-catalyzed synthesis of pyrroles from alpha-ethoxycarbonyl vinyl azides and ethyl acetoacetate through the 1,4-addition reaction of the acetoacetate to the vinyl azides. By applying these two methods, regioisomeric pyrroles can be prepared selectively starting from the same vinyl azides.
D001386:Azides / Q000737:chemistry*; D007659:Ketones / Q000737:chemistry; D015394:Molecular Structure; D011758:Pyrroles / Q000138:chemical synthesis* / Q000737:chemistry; D014753:Vinyl Compounds / Q000737:chemistry*
D001386:Azides; D007659:Ketones; D011758:Pyrroles; D014753:Vinyl Compounds