We report a novel metal organic framework (MOF) based on a cobalt arylphosphonate, namely, [Co2(H4-MTPPA)]·3NMP·H2O (1·3NMP·H2O), which was prepared solvothermically from the tetrahedral linker tetraphenylmethane tetrakis-4-phosphonic acid (H8-MTPPA) and CoSO4·7H2O in N-methyl-2-pyrrolidone (NMP).