Brønsted Acid–Catalyzed Meyer–Schuster Rearrangement for the Synthesis of α,β-Unsaturated Carbonyl Compounds

Abstract

An efficient and simple protocol for the Meyer–Schuster rearrangement of propargyl alcohols into α,β-unsaturated carbonyl compounds has been developed using catalytic amounts of p-toluenesulfonic acid in 1,2-dichloroethane.

GRAPHICAL ABSTRACT

Keywords:

• α,β-Unsaturated carbonyl compounds
• Brønsted acid
• Meyer–Schuster rearrangement
• p-toluenesulfonic acid
• propargyl alcohols

Notes

^a Reaction conditions: 1-phenyl-2-propyn-1-ol (1a, 1.0 mmol), solvent (3.0 mL), in air.

^b Yields are based on 2a, determined by crude ¹H NMR using dibromomethane as the internal standard.

^c As observed by ¹H NMR.

^d Isolated yield.

^a Reaction conditions: propargyl alcohols (1.0 mmol), PTSA (30 mol%), DCE (3.0 mL), in air.

^b Isolated yields.