Inclusion Compounds of Bulky Binaphthyl-type Bis-fluorenol Hosts

Abstract

Inclusion properties of a new family of clathrate hosts(1 -4) containing two 9-hydroxy-9-fluorenyl units or chloro-, bromo-and t-butyl-substituted derivatives of this group attached in the 3,3 0 -position to a basic 2,2 0 -binaphthyl construction element are reported (115 examples of clathrates). The crystal structures of six selected clathrates, involving dimethylsulfoxide, cyclopentanol, diethylether, benzylamine, chloroform and acetone as the guest, have been determined by X-ray diffraction, showing varied modes of supramolecular interaction dependent on the host and guest constitutions, while the formation of an intramolecular hydrogen bond between the hydroxy groups of the fluorenol units is a common structural feature (except in 3a) controlling twisted conformation of the host molecules.

Identifying a Hidden Conglomerate Chiral Pool in the CSD

“… Potential ligands and organocatalysts from conglomerate crystals. The following crystal structures, labeled by their CSD Refcode, were identified as conglomerates: OBIPAR, 122 LUZOO, 123 PURJUJ, 135 NULZEA, 128 KAQMEV, 167 DOBWUN, 126 ROJPOW, 124 TUWFAT, 125 HARFEN, 134 YAMBAS, 133 CUVGAB, 130 GADTIR, 168 NOCNIC, 129 TUNMOF, 127 QEVSAO, 169 VARLIK, 170 RIPBUN, 131 AZUDAB. 132 …”

“…Potential ligands and organocatalysts from conglomerate crystals. The following crystal structures, labeled by their CSD Refcode, were identified as conglomerates: OBIPAR, 123 LUZOO, 124 PURJUJ, 136 NULZEA, 129 KAQMEV, 168 DOBWUN, 127 ROJPOW, 125 TUWFAT, 126 HARFEN, 135 YAMBAS, 134 CUVGAB, 131 GADTIR, 169 NOCNIC, 130 By tracking materials which undergo this type of crystallization, the possibility of exploiting a powerful mode of chiral amplification can be achieved, whereby a substrate is able to bias its own enantioenrichment. The exciting synthetic potential of conglomerate crystallization has been demonstrated in the case of the natural product Narwedine.…”

Separation of Lutidine Isomers by Selective Enclathration

“…The host compounds, H1 , H2 , and H3 were synthesized by Weber ,, and were used without further purification. The lutidine guest compounds were all purchased from Sigma-Aldrich and used as received.…”

Inclusion of picolines by a substituted binaphthyl diol host: selectivity and structure

“…The torsion angles s 1 , s 2 and s 3 are remarkably constant in the structures I to IV, and in other inclusion compounds formed with this host and other guests, which have been previously published. [13][14][15] s 1 varies from À82.4 to À96.7 , s 2 from 18.7 to 26.3 and s 3 from 17.8 to 32.5 .…”

“…12 The host compound 3,3 0 -bis(9-hydroxy-9-uorenyl)-2,2 0 -binaphthyl, also following this construction principle, is built on a central biaryl unit with the bulky 9-hydroxy-9-uorenyl moiety attached, and it has proved to be a versatile host compound, enclathrating a variety of guest molecules with differing host : guest ratios. 13 It has also been employed as an efficient sensor for acetone vapour, and the structure of the inclusion compound as well as the thermodynamic data for acetone enclathration, have been announced. 14 This compound was also analysed by solid-state NMR, which allowed the identication of differently bound guest acetone molecules from distinct chemical shis obtained from the inclusion compounds.…”