Dissolve the carbonate in Et2O, wash with H2O (3x) and saturated aqueous NaCl, dry (MgSO4), evaporate this in a vacuum and recrystallise the residue from a small volume of MeOH, m 78-79o. Alternatively dissolve it in Et2O, wash it with N HCl (2x), 0.5N NaHCO3 (4x) then H2O, dry (Na2SO4), evaporate the Et2O and recrystallise the residue from *C6H6/pet ether, m 79-80o. The 2-nitro-isomer has m 27-28o, b 151o/11mm. [Khosla et al. Indian J Chem 5 279 1967, Wolman et al. J Chem Soc (C) 596 1976, Beilstein 6 IV 2277.]
