Self-assembly of two- and three-dimensional coordination networks with hexamethylenetetramine and different silver(I) salts

Interesting two-dimensional networks with square or hexagonal cavities, and three-dimensional networks with different channels, have been obtained by varying the counterions, the molar ratio of metal to hmt (hmt = hexamethylenetetramine) and the pH values of the initial solutions. Among the eleven products isolated and structurally characterized, two have a metal-to-hmt molar ratio of 2:1 and are the first examples of Ag-hmt square networks, namely Ag2(mu4-hmt)(NO2)2] (1) and Ag2(mu4-hmt)(SO4)(H2O)].4H2O (2), two have a metal-to-hmt molar ratio of 1:1 and are 2-D networks with hexagonal cavities, namely Ag(micro3-hmt)(NO2)] (3) and Ag2(micro3-hmt)2](S2O6).2H2O (4), and seven present the metal-to-hmt molar ratios of 3:1, 2:1, 3:2, or 4:3 and are 3-D networks of novel topologies and with different channels, namely Ag2(mu4-hmt)(micro4-ox)] (5), Ag3(micro4-hmt)2(H2O)2](SO4)(HSO4). 2H2O (6), Ag2(mu4-hmt)(mu2-O2CMe)](MeCO2).4.5 H2O (7), Ag2(mu4-hmt)(mu3-maleate)].5H2O (8), Ag3(mu4-hmt)(mu2-O2CPh)3] (9), Ag4(mu4-hmt)3(H2O)](SO4)(NO3)2.3H2O (10), and Ag12(mu4-hmt)6(mu3-HPO4)(mu2-H2PO4)3(H2PO4)7(H2O)](H3PO4).10.5H2O (11).