Catalytic enantioselective conjunctive cross-couplings that employ Grignard reagents are shown to furnish an array of non-racemic chiral organoboronic esters in an efficient and highly selective fashion. The utility of sodium triflate in facilitating this reaction is two-fold: it enables "ate" complex formation and overcomes catalytic inhibition by halide ions.

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Aryl alkynoate esters undergo gold-catalyzed spirocyclization under mild conditions, affording spirolactones in high yields. This approach obviates the need for stoichiometric halogenating reagents typically employed for alkyne activation in related transformations. Water was found to play a critical role in governing the product selectivity. Anhydrous conditions lead selectively to coumarin products, as has previously been observed for aryl alkynoate esters, while the addition of 1 equiv of water leads selectively to spirocycle formation.