Oligomer and Polymer: Self Assembly of [Cp*Fe(η5‐P5)] and Ag(I) Salts of Bulky Weakly Coordinating Anions

Abstract

AbstractReactions between the five‐fold symmetric building block [Cp*Fe(η5‐P5)] (A) and Ag(I) salts containing bulky weakly coordinating anions [TEF] and [FAL] ([TEF]=[Al{OC(CF3)3}4]–, [FAl]=[FAl{OC6F10(C6F5)}3]–) are presented. While, in the presence of Ag[TEF], A leads to the formation of a hitherto condensed 1D coordination polymer [{Ag(η2:η1‐A)2}]n[TEF]n (1), a new finite tetranuclear Ag(I) complex [{Ag4(η1‐A)2(η2:η1‐A)4(η1:η1‐A)2}][FAL]4 (3) was obtained with an Ag(I) salt bearing the weakly coordinating anion [FAl] increased in size. Various coordination modes (η2:η1; η1:η1 and η1) of A were observed in the solid‐state structure of 3, reflecting the adaptive coordination behavior of A towards Ag(I) ions. Structural modifications of the 1D polymer (1) can be controlled by the addition of a limited amount of MeCN yielding the unwound heteroleptic 1D polymer [{Ag(MeCN)2}3(η1:η1:η1‐A)2]n[TEF]3n (2). Moreover, in the presence of MeCN, the finite oligomeric compound 3 can also be converted into a new heteroleptic 1D polymer [{Ag(MeCN)}4(η1:η1‐A)5(η2:η1‐A)2]n[FAL]4n (4). The solid‐state structure of 4 discloses the existence of a unique 1,1,2‐η2:η1 (π,σ) coordination of A along with 1,3‐η1:η1 (σ) and 1,2‐η1:η1 (σ) coordination modes, while 1,2,4‐η1:η1:η1 (σ) coordination modes of A were found in 2. As revealed by X‐ray crystallography, in all the cases, the cationic moieties are well separated from the weakly coordinating anions in the solid state.