Efficient syntheses of imidazolo[1,2-a]pyridines and -[2, 1-a]isoquinolines.
2-Aminopyridines 1a-c and 1-aminoisoquinoline with 1-chloromethylbenzotriazole give 2-amino-1-[alpha-benzotriazol-1-ylmethyl]pyridinium chlorides 2a-c and 1-amino-2-(alpha-benzotriazol-1-ylmethyl)isoquinolinium++ + chloride 12, respectively. Compounds 2a-c and 12 react with aryl aldehydes 3a-h to afford imidazolo[1,2-a]pyridines 7a-k and imidazolo[2, 1-a]isoquinolines 13a,b in good yields.
Katritzky
A R
AR
Center for Heterocyclic Compounds, Department of Chemistry, University of Florida, Gainesville, Florida 32611-7200, USA. katritzky@chem.ufl.edu
Qiu
G
G
Long
Q H
QH
He
H Y
HY
Steel
P J
PJ
D018360:Crystallography, X-Ray; D007202:Indicators and Reagents; D007546:Isoquinolines / Q000138:chemical synthesis*; D009682:Magnetic Resonance Spectroscopy; D011725:Pyridines / Q000138:chemical synthesis*
D007202:Indicators and Reagents; D007546:Isoquinolines; D011725:Pyridines