The Study Of Organooxotin Clusters Assembled With Methylresorcin[4]arene Cavitands

Assemblies of two methylresorcin[4]arene cavitands with Bu2 SnO and n-BuSn(O)OH afforded four organooxotin-cluster-based compounds, namely,[(Bu2Sn)2(μ3-O)(L1)(EtO)]2·2EtOH(1), [(Bu2Sn)2(μ3-O)(L2)(Et O)]2·2EtOH(2),[(BuSn)12(μ3-O)14(μ2-OH)6](L1)2·2EtOH(3) and [(BuSn)(μ3-O)(L2)]6·6(toluene)(4)(HL1 = C1-COOH-in and HL2 = C1-COOH-out). Both 1 and 2 exhibit similar dumbbell-like structures, where the skeletons of methylresorcin[4]arene cavitands stretch in different directions on account of the different configurations of the carboxylate groups of L1 and L2 anions. As a result, the C–H···π interactions lead to slightly distinct 1D supramolecular architectures of 1 and 2. 3 displays a sandwich-like structure based on one [(BuSn)12(μ3-O)14(μ2-OH)6]2+ macrocation and two L1 anions, where the macrocation is trapped in the dimeric L1 anions via O–H···O hydrogen bonds. The sandwiches further stack via π-π interactions to generate a supramolecular dimer. 4 shows an unusual giant paddle-wheel motif composed of a typical Sn6O6 drum and six L2 anions. The paddle-wheel motifs are further extended into a 2D supramolecular layer via π-π interactions. the luminescent properties of 2 and 4 and the preliminary anti-cancer activity of 4 were also investigated.