In order to construct the molecular based-on magnets consisting of pure organic spins, we have been studying on the hydrocarbon molecules having super high-spin ground state. In this work, hexakisdiazo compound 1d, nonakisdiazo one 2d, and pentadecakisdiazo one 3d, having dendritic structures and diphenylacetylenes as stiff linkages were designed. Their photoproducts, 1c, 2c, and 3c, are expected to have tridecet (S = 12/2), nonadecet (18/2), and hentriacontet (30/2) ground states, respectively. Polyketones, 1k , 2k, and 3k were prepared by repeating a Sonogashira coupling reaction and carbonyl groups were converted diazo ones by the standard procedure. The magnetic properties after irradiation of polydiazo dendrimers in frozen solutions were investigated by magneto/susceptometry. After irradiation, the values of saturation magnetization at 2 K indicated that the degree of photolyses of 1d , 2d, and 3d were 94, 91, and 74%, respectively. Field dependence of magnetization, Mmol, and temperature dependence of molar magnetic susceptibility, cmol, revealed that photo-generated carbenes interacted ferromagnetically through diphenylacetylene linkages within each molecule. Theoretical equation fitted the experimental data in Mmol, vs. H for 1c, 2c, and 3c to give S = 5.9, 7.8, and 9.9, respectively.
|Translated title of the contribution||Construction of Photo-responsible Organic Molecules Having Super High-spin Ground States|
|Number of pages||1|
|Publication status||Published - 2002|