Preparation of the isomeric azaindoline family by intramolecular carbolithiation.
An operationally convenient, one-pot, three-step sequence has been developed that provides access to 3-substituted 4-, 5-, 6-, and 7-azaindolines (2,3-dihydro-1H-pyrollopyridines) via intramolecular carbolithiation of the aryllithium derived from an appropriate (N,N-diallylamino)bromopyridine. Whereas cyclization proceeds as expected to give 1-allyl-3-methyl-4-azaindoline and 1-allyl-3-methyl-6-azaindoline following protonation of the 3-CH2Li group of the azaindoline, the isomeric 3-methyl-5-azaindoline and 3-methyl-7-azaindoline are generated as 3-methyl-N-allyl anions prior to quench with MeOH.
Bailey
William F
WF
Department of Chemistry, University of Connecticut, Storrs, CT 06269-3060, USA. William.Bailey@uconn.edu
Salgaonkar
Paresh D
PD
Brubaker
Jason D
JD
Sharma
Vijayata
V
D001372:Aza Compounds / Q000737:chemistry*; D007211:Indoles / Q000737:chemistry*; D007536:Isomerism; D008094:Lithium / Q000737:chemistry*
D001372:Aza Compounds; D007211:Indoles; C057812:indoline; D008094:Lithium