Triflates were prepared via addition of ketones 3a–c to 1.1. equiv LDA in THF at −78°C. After 10 minutes 1.05 equiv of PhN(Tf) 2 was added and reactions were allowed to warm to RT overnight. Reaction workup consisted of concd in vacuo followed by partitioning between ethyl acetate and water. The organic phase was washed with excess aqueous base, dried and concd to an oil that was used without further purification. All triflates contained small amounts of ...
