Synthesis and Structure of Methylsulfanyl Derivatives of Nickel Bis(Dicarbollide).

Sergey A. Anufriev,Kyrill Yu. Suponitsky,Oleg A. Filippov,Igor B. Sivaev

doi:10.3390/molecules24244449

Abstract

Symmetrically and unsymmetrically substituted methylsulfanyl derivatives of nickel(III) bis(dicarbollide) (Bu4N)[8,8′-(MeS)2-3,3′-Ni(1,2-C2B9H10)2], (Bu4N)[4,4′-(MeS)2-3,3′-Ni(1,2-C2B9H10)2], and (Bu4N)[4,7′-(MeS)2-3,3′-Ni(1,2-C2B9H10)2] were synthesized, starting from [Ni(acac)2]3 and the corresponding methylsulfanyl derivatives of nido-carborane (Bu4N)[10-MeS-7,8-C2B9H11] and (Bu4N)[10-MeS-7,8-C2B9H11]. Structures of the synthesized metallacarboranes were studied by single-crystal X-ray diffraction and quantum chemical calculations. The symmetrically substituted 8,8′-isomer adopts transoid conformation stabilized by two pairs of intramolecular C–H···S hydrogen bonds between the dicarbollide ligands. The unsymmetrically substituted 4,7′-isomer adopts gauche conformation, which is stabilized by two nonequivalent C–H···S hydrogen bonds and one short chalcogen B–H···S bond (2.53 Å, −1.4 kcal/mol). The gauche conformation was found to be also preferred for the 4,7′-isomer.

Highlights

Molecular switches are molecules or supramolecular assemblies that can exist in two or more stable states that differ in the mutual orientation of the components and which can be transformed from one state to another by means of various external stimuli via rotation of these components relative to each other [1]
The unsymmetrically substituted 4,70 -isomer adopts gauche conformation, which is stabilized by two nonequivalent C–H···S hydrogen bonds and one short chalcogen B–H···S bond (2.53 Å, −1.4 kcal/mol)
We found that the methylsulfanyl groups are to we found that the methylsulfanyl groups are able to stabilize the transoid conformationable of the stabilize the transoid conformation of the corresponding derivatives of cobalt and iron corresponding derivatives of cobalt and iron bis(dicarbollides) [8,8 -(MeS)2 -3,3 -M(1,2-C2 B9 H10 )2 ]−

Summary

Introduction

Molecular switches are molecules or supramolecular assemblies that can exist in two or more stable states that differ in the mutual orientation of the components and which can be transformed from one state to another by means of various external stimuli via rotation of these components relative to each other [1]. Bis(dicarbollide) complex, whereas the transoid conformation with ligand rotation angle 180 degree is preferred for nickel(III) bis(dicarbollide) [7,8,9,10]. Somewhat later, several such molecular switches were. Molecules 2019, 24, 4449 is preferred for nickel(III) bis(dicarbollide) [7,8,9,10] Somewhat later, several such molecular switches were synthesized [11,12]; it was found that the difference in energies between the transoid and gauche rotamers in the synthesized nickel(III)

Methods

Discussion

Conclusion