Exploring BH2CN-based hydrophobic hypergolic fuels and effective fuel “additives”: Imidazolylidene cyanoborane complexes

Abstract Two hydrophobic imidazolylidene-cyanoborane complexes were prepared by the introduction of {BH 2 CN} into the molecular formula via treatment of imidazolium iodide and NaBH 3 CN avoiding literature's tedious and hazardous procedures. These two complexes were fully characterized using IR spectroscopy, 1 H NMR and 13 C NMR spectroscopy and high-resolution mass spectrometer. The X-Ray structure of NHC-1 has been determined. NHC-2 was proved to be hypergolic with WFNA and displayed the attractive properties such as water immiscibility, wide liquid range ( T g  = −22 °C), short ignition delay time (13 ms), high density (0.98 g/cm 3 ), good density impulse ( ρI sp , 347 s g cm −3 ), showing the promising application potential as a fuel and an efficient fuel additive.