An Experimental NMR and Semi-Empirical Theoretical Study of the Conformation of Styrylchromones and Styryl Alkyl or Aryl Ketones (Benzylidene Ketones) †
The configurations and conformations of styrylchromones and benzylidene ketones were determined by NMR spectroscopy. The cyclisation of the former to xanthones was studied showing clear differences in reactivity. These structural aspects were rationalised with the help of AM1 calculations.
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