Synthesis of μ-Diborolyl Triple-Decker Complexes by Electrophilic Stacking. Similar Bonding Properties of Anions [CpCo(1,3-C₃B₂H₅)]⁻ and Cp⁻ toward Transition Metals

Abstract

Triple-decker complexes with a bridging diborolyl ligand CpCo(µ-1,3-C 3 B 2 Me 5 )M(ring) (M(ring) ) RuCp, 4; RuCp*, 5; Co(C 4 Me 4 ), 6) were synthesized by electrophilic stacking of the sandwich anion [CpCo(1,3-C 3 B 2 Me 5 )]with the [(ring)M(MeCN) 3 ] + cations. Structures of 4-6 were confirmed by X-ray diffraction. The electrochemical and spectroelectrochemical behavior of the complexes prepared was studied. DFT calculations of the redox potentials were also performed. Similar bonding properties of anions [CpCo(1,3-C 3 B 2 R 5 )]and [C 5 R 5 ] -(R ) H, Me) toward [M(ring)] + cations were established both experimentally (synthesis, electrochemistry, and X-ray diffraction) and theoretically (energy decomposition and Mulliken population analysis).

Synthesis of μ-diborolyl triple-decker complexes [CpCo(1,3-C3B2Me5)Ru(arene)]+

“…These salts are well soluble in polar organic solvents, such as CH 2 Cl 2 and acetone. Their structures were con *The synthesized cationic complexes were isolated as salts with anions PF 6 -and BPh 4 -.…”

“…The Ru···C 6 distance (1.705 Å) is similar to analo gous distances in the [Cp*Ru(C 6 H 6 )] + cation (1.710 Å) 9 and triple decker complex CpCo(C 2 B 3 Et 2 H 3 )Ru(p cymene) (1.698 Å). 10 The analysis of the unit cell packing of the [2b]PF 6 molecules shows that cations 2b and anions PF 6 -form mutually alternating layers (Fig. 2).…”

“…2). The PF 6 -anion par ticipates in two types of intermolecular interaction: C-H ... F and P-F ... π (Table 1).…”

“…1- 5 We have previously studied the reaction of the sandwich anion [CpCo(1,3 C 3 B 2 Me 5 )] -(1) with the monocationic half sandwich fragments [(C 5 R 5 )Ru] + (R = H, Me), resulting in the formation of the neutral triple decker complexes CpCo(1,3 C 3 B 2 Me 5 )Ru(C 5 R 5 ). 6 We have recently shown 7 that the similar reaction of an ion 1 with the dicationic fragments [(C 5 R 5 )M] 2+ (R = H, Me; M = Rh, Ir) affords the cationic triple decker complexes [CpCo(1,3 C 3 B 2 Me 5 )M(C 5 R 5 )] + . In the present work, we describe the reactions of sandwich anion 1 with the species [(arene)Ru] 2+ .…”

Metallacarboranes and their interactions: theoretical insights and their applicability

“…Experimental electrochemical studies have proven very useful to acquire the necessary data to elucidate these properties. 10,13 Therefore, the use of computational resources to expand the information within this field is drawing a lot of interest and experimental boron chemists will make use of this tool as a new routine.…”