Hydrogen-Bonded 3-D Network Structures of Lanthanide Aquo Ions and 4,4‘-Bipyridine with Carbaborane Anions

Abstract

A series of three-dimensional (3-D) hydrogen-bonded structures of lanthanide aquo ions and 4,4′-bipyridine (bpy) or protonated bpyH + as ligands and hydrogen-bonding tectons have been characterized by single-crystal X-ray crystallography, with both Cland [Co(C 2 B 9 H 11 ) 2 ]counteranions. All show related structures with unidirectional rectangular channels filled by additional bpy molecules for the complexes [Yb(H 2 O) 8 ](bpy) 2.5 Cl 3 ‚6.5(H 2 O) and [Yb(H 2 O) 8 ] 4 (bpy) 9.5 Cl 12 ‚24.5(H 2 O) or by [Co(C 2 B 9 H 11 ) 2 ]anions for the complexes [Ln(bpy)(H 2 O) 8 ] 2 (bpy) 10 [Co(C 2 B 9 H 11 ) 2 ] 6 ‚1.5(EtOH)‚15(H 2 O) where Ln ) La, Ce, [Sm(H 2 O) 5 (bpy) 2 (EtOH)]-[Sm(H 2 O) 6 (bpyH)(EtOH)](bpyH)(bpy) 10 [Co(C 2 B 9 H 11 ) 2 ] 8 ‚EtOH‚9(H 2 O), and [Ln(H 2 O) 6 (bpy)(bpyH 0.5 )] 2 [Ln(H 2 O) 7 (bpy)](bpyH) 2 -(bpy) 14 [Co(C 2 B 9 H 11 ) 2 ] 12 ‚n(EtOH)‚5(H 2 O) where Ln ) Gd, Tb, and Ho. The smaller (CB 11 H 12 )anion does not template a similar structure; instead the complex [(bpyH) 3 (bpy)(CB 11 H 12 ) 3 ] is isolated with a one-dimensional (1-D) hydrogen-bonded ladder structure.

The Role of C–H···H–B Interactions in Establishing Rotamer Configurations in Metallabis(dicarbollide) Systems

“…[14,[23][24][25][26][27] In this respect, all solid-state structures containing the transoid rotamer/s present some peculiar characteristics: a) they have more than one type of rotamer in the asymmetric unit and b) the salt formulation could be consistent with a cobaltabisdicarbollide either as Co II or Co III oxidation states, due to the ambivalent nature of the cation. [14,23] The latter consideration could lead to interpret that the oxidation state of Co predominates to define the rotamer.…”

Carba‐closo‐dodecaborates – Synthesis, Structure, and Energetics

“…Until now only four X‐ray crystallographic structures of nido ‐cage compounds 1 are known. The authors of these structural reports assumed bridging H atoms on the upper meta ‐boron‐belt in highly disordered anions (Figure , left) , . In the liquid phase, dynamic behavior of the protons is observed.…”

“…Gas‐phase DFT calculations (pbe0/aug‐cc‐pwCVDZ, see below) agree well with data obtained from solid‐state X‐ray structure elucidations. The solid‐state structural data of all investigated anions 1 – 4 have already been reported, but in combination with other cations such as [Ph 3 PH] 1 , [Bpy‐H] 2 , [Ph 3 C] 3 , and [Ph 3 C] 4 ; therefore, we abstain here from a detailed structural discussion.…”

Noncovalent Interactions at Lanthanide Complexes

“…In fact, the La• As highlighted by the above examples, an appropriate design of the organic ligands allows to synthesize lanthanide complexes with various types of noncovalent interactions on the secondary coordination sphere, which can be an important synthetic strategy for the construction of new functional materials. Although the essential roles of several noncovalent interactions in the synthesis, structure, self-assembly and catalytic action of lanthanide complexes have already been illustrated/reported in many experimental works, [82][83][84][85][86][87][88][89][90][91][92] there is not a review on the crucial role of these weak forces in lanthanide chemistry. Moreover, due to their recent experimen-Scheme 2.…”