Cyclization of 1,3-ynones and o-aminothiophenol^a.

^aReaction conditions: 0.5 mmol of 1,3-ynone, 0.6 mmol of o-aminothiophenol in the presence of 5 mol% Cp₂ZrCl₂, 10 mol% of l-phenylalanine and 1 mL DMF at room temperature for 5 h, then 0.6 mmol I₂ was added for 1 h. Isolated yields were obtained after purification by column chromatography.