The reaction heats and PM5 semiempirical studies of complexes formed between silicon podand and monovalent cations

Silicon podands (1–10) were synthesised and their complexation reaction of NaC cations were studied by calorimetric and PM5 theoretical methods. Both methods provide evidence for formation of the respective complexes with NaC cations of different stoichiometry. In most cases, only formation of the complexes of 1:1 stoichiometry has been observed. For compounds with longer oxaalkyl chains (9 and 10) the formation of 1:4 and 1:6 complexes has been found. The structures of the complexes are visualised and discussed. q 2004 Elsevier B.V. All rights reserved.