Free radical-mediated aryl amination: convergent two- and three-component couplings to chiral 2,3-disubstituted indolines.
5-exo-trig Cyclization of an aryl radical to the nitrogen of an azomethine is used as the key annulating step in a modular preparation of 2,3-cis- and trans-disubstituted indolines. The precursors are readily prepared by phase-transfer-catalyzed Michael addition of a glycine Schiff base to a variety of acceptors. When the more reactive alkylidene malonate Michael acceptors are implemented, a one-pot three-component coupling is possible. The net result is a convergent [3 + 2] coupling strategy for the construction of highly functionalized indolines, a substructure occurring in numerous biologically active natural products.
Viswanathan
Rajesh
R
Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, Tennessee 37235-1822, USA.
Smith
Colin R
CR
Prabhakaran
Erode N
EN
Johnston
Jeffrey N
JN
D000478:Alkylation; D000586:Amination; D001372:Aza Compounds / Q000737:chemistry; D004952:Esters / Q000737:chemistry; D005609:Free Radicals / Q000737:chemistry; D007211:Indoles / Q000737:chemistry*; D008956:Models, Chemical; D015394:Molecular Structure; D013237:Stereoisomerism
D001372:Aza Compounds; D004952:Esters; D005609:Free Radicals; D007211:Indoles; C057812:indoline