Synthesis of indoles via palladium[0]-mediated Ullmann cross-coupling of o-halonitroarenes with alpha-halo-enones or -enals.
[reaction: see text] Palladium[0]-mediated Ullmann cross-coupling of o-halonitrobenzene (1) and various related nitroarenes with a range of alpha-halo-enones (e.g., 2) or -enals readily affords the expected alpha-arylenones, e.g., 3, or -enals, which are converted into the corresponding indoles, e.g., 4, on reaction with dihydrogen in the presence of Pd on C.
Banwell
Martin G
MG
Research School of Chemistry, Institute of Advanced Studies, The Australian National University, Canberra, ACT 0200, Australia. mgb@rsc.anu.edu.au
Kelly
Brian D
BD
Kokas
Okanya J
OJ
Lupton
David W
DW