A Simple and Efficient Palladium Catalyst of Nitrogen-Based Ligand for Cu(I)- and Amine-Free Sonogashira Reaction

<div><p></p><p>Glycine, as a kind of commercially available and inexpensive ligand, is used to prepare an air-stable and water-soluble catalyst used in Sonogashira reaction in our study. In the presence of 1% [PdCl₂(NH₂CH₂COOH)₂] as catalyst, excellent catalytic activity towards the Sonogashira coupling of aryl iodides with terminal alkynes without using any additive such as Cu(I)-cocatalyst is observed in a mixture of water and acetone (3/3 mL) under air at 60 °C with NaOH as a base, giving products in good to excellent yields.</p>