Microwave-assisted solvent-free instantaneous Claisen rearrangement for synthesis of bis(3-allyl-4-hydroxyphenyl) sulfone

Solvent- free Claisen rearrangement of bis( 4- allyloxyphenyl) sulfone ( 1) under microwave irradiation for 5 min gave high yields of bis( 3- allyl- 4- hydroxyphenyl) sulfone ( 3), which has been synthesized up to now under conventional heating for 2 - 30 h as a color developer for a heat- or pressure- sensitive recording in industry.