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Aryl annulation of cyclic ketones via a magnesium carbometalation-6-pi- electrocyclization protocol. | LitMetric

A new strategy for the aryl annulation of cyclic ketones is described. Palladium(0) coupling of a propargyl alcohol with the enol triflate of a ketone and addition of vinylmagnesium chloride generates a triene as a magnesium chelate that may be quenched with an electrophile. In some cases, the triene cyclizes under the reaction conditions. Aromatization is accomplished by exposure to manganese dioxide or dichlorodicyanoquinone (DDQ). [reaction: see text]

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http://dx.doi.org/10.1021/ol047602yDOI Listing

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