SbCl₃-catalyzed solvent-free Friedel–Crafts reaction of phenols with mandelic acids to 3-aryl benzofuran-2(3H)-ones: Synthesis of spirocyclic 2,3-dihydrobenzofuran-2-ones

ABSTRACT

A facile, SbCl₃-catalyzed, one-pot, tandem Friedel–Crafts/lactonization reaction of phenols and mandelic acids has been developed under solvent-free conditions to afford 3-aryl benzofuran-2(3H)-ones in good to high yields (52–90%). Additionally, the utility of 3-aryl benzofuran-2(3H)-ones is demonstrated by using them as precursors in the synthesis of a new class of spirocyclic benzofuran-2-ones using classical synthetic methodologies.

GRAPHICAL ABSTRACT

KEYWORDS:

• Antimony(III) chloride
• 3-aryl benzofuran-2(3H)-one
• Friedel–Crafts reaction
• mandelic acid
• spirocyclic benzofuran-2-one

Acknowledgment

The authors gratefully thank Professor I. N. N. Namboothiri (IIT, Mumbai, India) for HRMS data.