[Biphenyl derivatives as by-products from the synthesis of 4-aryl-4H-pyrans].
The reaction of the 1,5-diketones 1 with acetic anhydride/acetic acid in the presence of zinc chloride yields the 4-aryl-4H-pyrans 2 as main products. The annulated lactone 3 and the cyclohexene derivatives 5 are isolated as by-products. The configuration of the cyclohexanone 4a and the cyclohexenes 5 are deduced from nmr spectroscopic methods. The structure of 5b is confirmed by X-ray crystal analysis.
Görlitzer
K
K
Institut für Pharmazeutische Chemie der Technischen Universität Braunschweig, Germany. k.goerlitzer@tu-bs.de
Trittmacher
J
J
Jones
P G
PG
D001713:Biphenyl Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D018360:Crystallography, X-Ray; D003510:Cyclohexanes / Q000138:chemical synthesis / Q000737:chemistry; D007202:Indicators and Reagents; D007783:Lactones / Q000138:chemical synthesis / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D008958:Models, Molecular
D001713:Biphenyl Compounds; D003510:Cyclohexanes; D007202:Indicators and Reagents; D007783:Lactones