Ozonolysis of furans

On treatment of furan at low temperature with hydrogen peroxide the peroxide (53) is obtained which may be partially hydrogenated to malealdehyde. 2,5-DimethyIfuran with acidic hydrogen peroxide yields the hydroperoxide (54) and the cyclic peroxides (55) and (56) mechanisms have been proposed. Ozonolysis of furan at -60 °C in chloroform with reductive work up affords glyoxal and formic acid. Methylfurans behave similarly thus... 

The ozonolysis of furan itself yields glyoxal (about 46% by weight) and formic acid. Interesting results, however, have been obtained in the ozonolysis of methyl furans. 

---