Diorganostannoxanes Stabilized by Intramolecular N→Sn Coordination Approach: Synthesis, Structure, TD-DFT and Hirshfeld Surface Analysis

A mononuclear diorganotin halide and two dinuclear diorganostannoxanes containing Sn-O unit were synthesized using intramolecular coordination approach involving 2-phenylazophenyl substituent on tin. [(R2Sn)2(μ2-O)Cl2]·CH2Cl2 (1) was obtained by partial hydrolysis of R2SnCl2 (R = 2-phenylazophenyl) using equimolar sodium hydroxide whereas, [R2Sn(cupf)Cl] {cupf= cupferronato} (2) was obtained by the room temperature reaction of cupferron with R2SnCl2. [(R2Sn)(μ2-OH)(OOCCH=CHC6H5)]2·2H2O (3) was obtained by the reaction of cinnamic acid and R2SnO (R = 2-phenylazophenyl) in refluxing toluene. The molecular structures of complex 1–3 were established using single crystal x-ray crystallography. Time dependent density functional theory (TD-DFT) calculations revealed that the transitions occurring in 1–3 are mainly ligand-to-ligand type. Intermolecular interactions in 1–3 were studied using Hirshfeld surfaces. 2D fingerprint plots illustrated that supramolecular assemblies of 1 and 2 were influenced majorly by CH…π, N…H, Cl…H and O…H interactions whereas supramolecular assembly of 3 mainly consisted of CH…π, N…H and O…H interactions.