Supramolecular Interactions as Determining Factors of the Geometry of Metallic Building Blocks:Tetracarboxylate Dimanganese Species

摘要

Notwithstanding the richness of manganese carboxylate chemistry,~[1] dimanganese tetracarboxylate species with a copper acetate-like core have been characterized only recently.~[2] At the time of our report on [Mn(tda)(bipy)]n (1) (tda = thiodiacetate = S(CH_2COO)22";bipy = 2,2'-bipyri-dine),~[2] the only other known examples either lacked detailed structural information ([Mn_2(C_3F_7CO_2)_4(bipy)_2]~[3]) or had not been deposited in the Cambridge Structural Database'4' ([Mn_2(Ph_2XCCO_2)_4(quinoline)_2];~[5] X = H,Me).Another example,[Mn_2((j,-OOOBu)_4fOC(fBu)OHNEt_3}_2],has appeared recently.~[6] In 1,the bimetallic {Mn_2(ji-carboxyl-ate)_4) units,completed by two terminal bipy ligands and interconnected by pairs of CH_2SCH_2 spacers,form linear chains which further organize into a supramolecular structure through noncovalent interactions.'781 Copper acetate itself and other metal carboxylate synthons often generate metal-organic frameworks (MOF) through coordinative bonds,'7' whereas the overall architecture of 1 stems from the interactions between the ID polymeric chains.In fact,the bipy ligands of adjacent chains,which are all parallel to each other,are jt-stacked in a gearlike arrangement with the formation of compacted 2D sheets.In order to understand better the correlations between the geometry of the building blocks and the given supramolecular structure,we have tried to combine the Mn-tda unit with other N-donor chelating ligands.