Leaving group and regioselectivity switches in the aminoalkylation reaction of indoles and related heterocycles with α-amido sulfones

Article abstract of DOI:10.1002/ejoc.201300369

The regioselective aminoalkylation of indoles and related heterocycles with α-amido sulfones under basic conditions has been studied. The reaction that employed the MeMgBr/MgBr₂ system provided high yields of 3-(1-carbamoylalkyl)indoles. On the other hand, the reaction that used Cs ₂CO₃ afforded 1-(1-carbamoylalkyl)indoles exclusively in high yields. The first reaction constitutes a switch of the leaving group of the α-amido sulfone in comparison to previously reported reactions between indoles and α-amido sulfones, which provided 3-(1-arylsulfonylalkyl) indoles. The second reaction constitutes a switch in the regioselectivity. The extensions of these C- and N-aminoalkylations starting from pyrroles and 7-azaindole have also been studied. Structurally diverse aminoalkylated indoles, pyrroles, and 7-azaindoles were obtained with excellent yield in most of the cases. The regioselective aminoalkylation of indoles and heterocycles with α-amido sulfones under basic conditions is described. The reaction with MeMgBr/MgBr₂ gives 3-(1-carbamoylalkyl)indoles, whereas employing Cs₂CO₃ yields 1-(1-carbamoylalkyl)indoles. The first case presents a switch of the leaving group of the α-amido sulfone, whereas the second demonstrates a switch in the regioselectivity. Copyright