A Revisit to the Hantzsch Reaction: Unexpected Formation of Tetrahydrobenzo[b]pyrans beyond Polyhydroquinolines

作者：Undale Kedar A; Park YoonKook; Park Kyungmoon; Dagade Dilip H; Pore Dattaprasad M^*

来源：Synlett, 2011, (6): 791-796.

DOI：10.1055/s-0030-1259924

• multicomponent synthesis
• tetrahydrobenzo[b]pyrans
• ammonium acetate
• semi-emperical calculations

A competitive multicomponent synthesis of tetrahydrobenzo[b]pyrans over polyhydroquinolines is achieved in the presence of ammonium acetate at ambient temperature in ethanol medium. The formation of tetrahydrobenzo[b]pyran instead of polyhydroquinoline in solution phase has been confirmed by spectral and single-crystal analysis. The mechanism for the above transformation is suggested and supported by semi-empirical calculations of heat of formation for the intermediates as well as products.

• 出版日期2011-4-1