Ultrasound in lipid chemistry,cyclopropanation of unsaturated fatty esters and triglycerides

Concomitant ultrasonic irradiation during the Simmons-Smith reaction facilitated the cyclopropanation of ethylenic fatty esters and triglycerides. Methyl ricinoleate furnished predominantly the corresponding hydroxy cyclopropanoid ester when the reaction was carried out at 85–95 C under ultrasound in the presence of zinc, while a C₁₈ furanoid fatty ester gave a novel tricyclo derivative (methyl 9,12-epoxy-9,10;11,12-dimethanooctadecanoate).