Methylene Insertion into Nitrogen‐Heteroatom Single Bonds of 1,2‐Azoles via a Zinc Carbenoid: An Alternative Tool for Skeletal Editing

Abstract

Abstract The nitrogen‐heteroatom single bonds of 1,2‐azoles and isoxazolines underwent methylene insertion in the presence of CH2I2 (6 equiv.) and diethylzinc (3 equiv.) to produce a wide variety of the ring‐expanded six‐membered heterocycles. Density functional theory calculations suggest that the methylene insertion proceeds via cleavage of nitrogen‐heteroatom single bonds followed by ring closure.

Keywords

• 1, 2‐azole
• ring expansion
• zinc carbenoid