Synthesis of 3-alkyl-2,5-dimethylfuran derivatives by indirect alkylation of 2,5-dimethylfuran with aliphatic nitrocompounds

The preparation of 3-alkyl-2,5-dimethylfuranes via indirect alkylation of 2 ,5-dimethylfuran is reported. Thus, primary nitroalkanes react with cis-3-h exen-2,5-dione giving a tandem Michael addition/elimination of nitrous acid , followed by chemoselective hydrogenation of the C=C double bond of the ob tained enones. The Paal-Knorr reaction, performed with p-toluenesulfonic ac id in diethyl ether, completes the formation of the title compounds. In thi s context the nitroalkane can be considered as an alkyl cation synthon.