| Title | The Catalytic Synthesis of N-Aryl Indoles Featuring an Alternative Disconnection. Hydroaminoalkylation for a Telescoped Reaction Sequence |
| Publication Type | Journal Article |
| Year of Publication | 2022 |
| Authors | Zheng, CHM, Balatsky, DA, DiPucchio, RC, Schafer, LL |
| Journal | Organic Letters |
| Volume | 24 |
| Start Page | 6571-6575 |
| Abstract | A tricatalytic telescoped synthesis toward C3-methyl-N-aryl indoline and indole products is reported. An in situ generated tantalum(V) ureate catalyst is used for the hydroaminoalkylation of o-chlorostyrene with N-methylaniline to first make a Csp3─Csp3 bond. Subsequent nickel-catalyzed C–N coupling forms N-aryl indolines, and if desired, subsequent oxidation to N-aryl indoles can be achieved using catalytic [Cu(MeCN)4]BF4 and tert-butylperoxy-2-ethylhexyl carbonate as the terminal oxidant. This strategy highlights an alternative C–C bond disconnection for the synthesis of indoles, which is enabled by the atom-economic hydroaminoalkylation reaction. The method was streamlined using a three-step, two-pot approach to afford up to 73% overall isolated yield of variously substituted C3-methyl-N-aryl indoles. |
