A series of 6‐arylhydrazono‐6,7,8,9‐tetrahydro‐11H‐pyrido[2,1‐b]quinazolin‐11‐ones 3–37, conveneint starting materials for indolopyridoquinazolines, were prepared by diazonium coupling between aryldiazonium chlorides and 6,7,8,9‐tetrahydro‐ 2, 6‐formyl‐5,7,8,9‐tetrahydro‐ 39, 6‐(dimethylamino)methylene‐6,7,8,9‐ 38 or 6‐carboxyl‐5,7,8,9‐tetrahydro‐11H‐pyrido[2,1‐b]quinazolin‐11‐ones 43. The arylhydrazono derivatives were also prepared from 6‐bromo‐ 45 or 6,6‐dibromo‐6,7,8,9‐tetrahydro‐11H‐pyrido[2,1‐b]quinazolines 46 with arylhydrazines. The structures of the 6‐arylhydrazonopyridoquinazolines were characterized by uv and 1H nmr spectroscopy. The 6‐arylhydrazono derivatives show a solvent‐dependent E‐Z isomerism.
ASJC Scopus subject areas
- Organic Chemistry