Boron trifluoride → 5-Methoxy-3-phenyl-1-tetralone

Beteiligte Stoffe

Reaktionsschritte

o-Anisaldehyde (20.5 g) was treated with 1,3-propanedithiol (24 ml) in the presence of BF3 etherate (4 ml) and CH2Cl2 (300 ml). This dithiane derivative (4.7 g) was reacted with n-BuLi (2.5 M hexane solution) (7.3 ml), methyl cinnamate (3.4 g) and 1,3-dimethyl-2-imidazolidone (4.6 ml) affording the desired product (M+H)+ 389. Desulfurization was accomplished with Raney Nickel and EtOH, followed by hydrolysis to the desired carboxylic acid. Cyclization to the desired 5-methoxy-3-phenyl-1-tetralone was accomplished by heating with polyphosphoric acid, (M+H)+ 253.

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