Selectivity behaviour of two roof-shaped host compounds in the presence of xylene and ethylbenzene guest mixtures

Abstract

In the present investigation, we compare the host and selectivity behaviour of two compounds, namely α,α-diphenyl-9,10-dihydro-9,10-ethanoanthracene-11-methanol H1 and α,α-bis(p-chlorophenyl)-9,10-dihydro-9,10-ethanoanthracene-11-methanol H2, when recrystallized from both singular and mixed isomers comprising the...

Complementary host behaviour of three anthracenyl-derived roof-shaped compounds in mixed pyridines

“…The roof-shaped compounds derived from anthracene and fumaric acid were designed by Edwin Weber in 1996 and were shown to be highly effective host compounds for the complexation of a large variety of guest species. 15 In subsequent investigations in our own laboratories, these types of host compounds were demonstrated to possess enhanced selectivities in aromatic positional isomeric mixtures such as the xylenes (and ethylbenzene), 16–18 dichlorobenzenes, 19 the MePys (and Py), 20 methylanisoles (and anisole), 21,22 and bromoanisoles (and anisole). 23 In many of these recrystallization experiments that employed guest mixtures, host selectivity coefficients ( K ) were significant (greater than 10), alluding to the feasibility of separating such mixtures on a practical platform, as reported by Nassimbeni and co-workers.…”

Evaluation of the Behavior of Two Tricyclic-Fused Host Systems in the Presence of Single and Mixed Isomers of the C8H10 Aromatic Crude Oil Fraction

“…It was reported that, more specifically, N , N ′-bis­(5-phenyl-5-dibenzo­[ a , d ]­cycloheptenyl)­ethylenediamine and its 10,11-dihydro analogue, N , N ′-bis­(5-phenyl-10,11-dihydro-5-dibenzo­[ a , d ]­cycloheptenyl)­ethylenediamine, possessed an overwhelming preference for p Xy and o Xy, respectively, when presented with such mixtures. Furthermore, other tricyclic fused systems based on the xanthenyl and thioxanthenyl systems have demonstrated selectivity behavior in such mixtures, favoring either p Xy or o Xy, dependent upon the molecular structure of the host compound employed. − Additionally, it has been reported recently that the host compound derived from tartaric acid, ( R , R )-(−)-2,3-dimethoxy-1,1,4,4-tetraphenylbutane-1,4-diol, possessed an affinity for, also, the para isomer, while four roof shaped host compounds synthesized from anthracene by means of a Diels–Alder reaction also behaved selectively in EB/Xy mixtures. − Interestingly, among all of these host compounds, only trans -α,α,α′,α′-tetra­(4-chlorophenyl)-9,10-dihydro-9,10-ethanoanthracene-11,12-dimethanol preferentially selected the meta isomer, while EB was never a favored guest species.…”

Selected Tricyclic Fused Systems: Host Behavior in the Presence of Mixed Xylenes and Ethylbenzene

“…Clearly, this field of chemistry has successfully served as a separatory tool for various guest mixtures. Indeed, in our own laboratories, we have investigated the potential of host compounds based on tartaric acid, xanthone, and thioxanthone, − and Edwin Weber’s roof-shaped host molecules , for the separation of Xy/EB mixtures. In an overwhelming majority of these experiments, the host compound displayed remarkable selectivity for one particular guest in the mixture, more usually p -Xy, but o -Xy also featured as the favored guest component in certain conditions.…”