Abstract
The results of absolute asymmetric photochemical studies on 5- and 7-membered spiroketones in the solid state are described. Photolysis of 7-membered spiroketone undergoing a Norrish type II cyclisation reaction gives enantioselectivity excesses up to 93%. Irradiation of 5-membered spiroketone afforded a racemic product. The results are rationalised by the X-ray crystallographic method.
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