Solid‐State Reactions of Eicosaborate [B₂₀H₁₈]²⁻ Salts and Complexes

Abstract

A series of salts and complexes containing trans- and iso-isomers of octadecahydro-eicosaborate [B H ] dianion is synthesized and characterized using FTIR and B NMR spectroscopies and X-ray diffraction techniques. Both isomers are found to act as four-, bi-, or zero-dentate ligands in reactions with copper(II), silver(I), and lead(II) through apical and/or equatorial boron atoms. Solid-state photo- and thermoinitiated reactions of octadecahydro-eicosaborate isomerization and solvent cleavage occurring in these compounds in a single-crystal-to-single-crystal manner are studied in situ. In contrast with solutions, in solids the reaction of boron cluster transformation occurs rarely, thus, analysis of crystal packing allowed us to suggest some criteria of isomerization of macropolyhedral boranes in crystals. X-ray diffraction data are used to confirm reaction path of isomerization of the [B H ] dianion.

Photochromic System among Boron Hydrides: The Hawthorne Rearrangement

“…Access to innovative and/or more efficient technological devices is directly linked to the development of usable functionalized materials such as responsive molecular switches. , Therefore, the growing needs of industry demand a systematic exploration of molecules displaying attractive photophysical and photochemical properties, requiring the fine understanding at a fundamental level of the molecular mechanisms that govern the photoprocesses coming into play. In this framework, boron hydrides − represent a family of compounds whose rich structural variety offers a diverse set of tunable optical properties with potential applications such as blue lasing, , strongly phosphorescent luminophores, singlet oxygen production, and energy-transfer composite materials . Other borane-based large systems have recently emerged as appealing materials for medicinal applications, whereas the functionalization of icosahedral boranes, carboranes, and metallacarboranes has a growing interest as alternatives to the traditional organic and organometallic material building blocks .…”

“…Among the polyhedral [ closo -B n H n ] 2– ions ( n = 5–12), those with n = 10, 12 are commonly used in boron cluster chemistry − and are characterized in terms of a 3c–2e multicenter bonding scheme . The icosahedral [ closo -B 12 H 12 ] 2– , with all boron atoms being equivalent, dimerizes without retaining the individual icosahedra, and consequently, three or four boron vertices are shared, yielding the macropolyhedrons B 20 H 16 and [B 21 H 18 ] − , respectively. , In contrast, the biccapped-square antiprismatic [ closo -B 10 H 10 ] 2– ion is quite reactive and undergoes dimerization in which two [ closo -B 10 H 10 ] 2– ions formally lose a hydride ion; the resulting [ closo -B 10 H 9 ] − ions produce the [ trans -B 20 H 18 ] 2– species .…”

Silver(I) and Copper(I) Complexation with Decachloro-Closo-Decaborate Anion

“…The atomic Hirshfeld surfaces (sAHS) proved themselves to be an easy and valuable tool for analysis of chemical bonding including multicentered one between metal atoms and boron cages [18,58,59]. Besides, the AHS can be used to compare chemical bonding for a series of similar compounds [60,61].…”

“…Boron clusters and their derivatives are considered as soft Lewis bases because of their large size and relatively low charge; quite logically, they form a great variety of inner-sphere complexes with metals that are soft Lewis acids, such as silver(I), copper(I), lead(II), etc. Different positions of metal atoms around a bulky boron cage results in the preparation of positional isomers of mononuclear and binuclear copper(I) and silver(I) complexes, which are discussed in detail in references [16][17][18].…”

Electrochemical Properties of the closo-Decaborate Anion [B10H10]2– and a New Method for Preparation of the [B20H18]2– Anion

“…The closo-decaborate anion [B 10 H 10 ] 2can serve as a basis for the preparation of octadecahydroeicosaborates [B 20 H 18 ] 2of various structures [26][27][28]. Interest in this class of substances is due to the fact that one octadecahydroeicosaborate molecule contains twice as many boron atoms as the closo-decaborate anion, which makes this class of compounds a promising starting platform for creating drugs for BNCT on its basis.…”