Aryl annulation of cyclic ketones via a magnesium carbometalation-6-pi- electrocyclization protocol.
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]
Tessier
Pierre E
PE
Department of Chemistry, University of Ottawa, 10 Marie Curie, Ottawa, Ontario, Canada K1N 6N5.
Nguyen
Natalie
N
Clay
Matthew D
MD
Fallis
Alex G
AG