Research Article

3-Bromopyridine-Heterogenized Phosphotungstic Acid for Efficient Trimerization of Biomass-Derived 5-Hydroxymethylfurfural with 2-Methylfuran to C21 Fuel Precursor

Figure 10

1H and 13C NMR spectra of intermediate 1. Intermediate 1: 1H NMR (500 MHz, CDCl3) (,  Hz, 1H), 6.05 (s, 1H), 6.04 (,  Hz, 1H), 5.97 (,  Hz, 2H), 5.89 (,  Hz, 1H), 5.89 (,  Hz, 1H), 5.40 (s, 1H), 4.55 (s, 2H), 2.25 (s, 6H). 13C NMR (126 MHz, CDCl3) , 152.85, 151.66, 150.24, 108.74, 108.05, 106.32, 57.68, 39.24, 13.67.