Synthesis of 2,4,5-Trisubstituted Furans via a Triple C(sp3)–H Functionalization Reaction Using Rongalite as the C1 Unit

A highly efficient I2/Cu­(NO3)2·3H2O-mediated triple C­(sp3)–H functionalization reaction for the synthesis of 2,4,5-trisubstituted furans from aryl methyl ketones and rongalite by employing rongalite as a C1 unit has been developed. This method allows rapid access to (2-acyl-4-methylthio-5-aryl) furans. Preliminary mechanistic studies indicate that in situ generated dimethyl­(phenacyl)-sulfonium iodine and HCHO were probably the key intermediates in this transformation.