Na2S2O4 (0.15 g, 0.86 mmol) as reducing agent was added to a stirred solution of Na2MoO4.2H2O (3 g, 12.4 mmol) in water (10 mL) which was acidified
with 0.5 H2SO4 (35 mL; immediate color change to blue). The solution was stored in a closed flask and after 2 weeks the precipitated deep-blue
crystals of 1 were collected by filtration, yield: 80 mg (two crystal types: major part showing from top view a characteristic form like an elongated
benzene molecule, while a much smaller fraction of the crystals is grown together).
Characteristic IR bands (KBr pellet): 1616 (m,(H2O)), 1191 (w), 1122 (w), 1060 (all as(SO4)), 975/954 (s) ((MoO)), 761 (s), 700 (sh), 627 (w),
555 (m), 464 (w) cm1; approximate wavenumbers of the very broad Raman bands (KBr dilution; e 1064nm): 810 (m), 680 (w), 460 (m) cm1; Vis (in
H2O): 740 (very broad) nm. |