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Synthesis of Dibenzotropones by Alkyne-Carbonyl Metathesis
Maryam Sobhani1, Anna Frey1, Andre Rettmann1
1Universität Rostock, Institut für Chemie, A.-Einstein-Str.3a, 18059 Rostock, Germany.
Abstract:
Dibenzocycloheptanones (dibenzotropones) were prepared by Brønsted acid mediated intramolecular alkyne-carbonyl metathesis (ACM) reactions. The cyclization precursors are readily available by Sonogashira reaction of 2-bromobenzoyl chloride with terminal alkynes, followed by Suzuki reactions with benzaldehydes. The ACM reactions are highly modular and atom economic and allow for the construction of two regioisomeric series of dibenzotropones.
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