Wheel-and-axle design as a source of host-guest compounds. The crystal structure of the 2:1 acetone: tetraphenyl-2,4-hexadiyne-1,6-diol complex

Crystal structure and DFT studies of N1,N6-Di(9H-fluoren-9-ylidene)hexane-1,6-diamine

“…The fluorenyl groups and the central alkyl groups constitute a ''wheel and axle''. The central alkyl groups act as the axle parts, and the two wheel parts are composed of fluorenyl groups and N atom, which is similar to the previous reports [25,26]. The adjacent molecules are stacked through strong offset p-p aromatic stacking interactions, with a face-to-face distance of 3.405 Å. Interestingly, the calculated angle (h) between the adjacent dipole center attachment and dipole directions is 38.32° (Fig.…”

Inclusion Compounds of Diol Hosts Featuring Two 9-Hydroxy-9-fluorenyl or Analogous Groups Attached to Linear Spacer Units

“…This general behavior is a reasonable consequence of the polar hydroxy groups present in the host compounds, making hydrogen bonding to the guest molecules very likely. It follows that apolar hydrocarbons are very rarely enclathrated by these hosts, indicating that ''true clathrates'' [25] are not favored among these compounds. More specific inclusion behavior associated with the structure of the host compounds is difficult to discern, although the length of the central spacer unit (cf.…”

meso- and rac-2,7-diphenyl-3,5-octadiyne-2,7-diol, C20H18O2

“…Structures of diyne-diols related to (I) have been reported by Toda and co-workers and have mainly involved clathrates of the three tetraaryl derivatives: 1,1,6,6-tetraphenylhexa-2,4-diyne-1,6-diol (Toda, Ward & Hart, 1981;Kaftory, Tanaka & Toda, 1985;Kaftory, 1987;Fukawa et al, 1989;Kaftory, Yagi, Tanaka & Toda, 1988;Toda, Tanaka, Kai et al, 1988;Toda, Tanaka, Asao et al, 1988), 1,1,6,6-tetrakis(3,4-dimethylphenyl)hexa-2,4-diyne-1,6-diol (Toda, Tanaka & Mak, 1985) and chiral 1,6-bis(2-chlorophenyl)-1,6-diphenylhexa-2,4-diyne-1,6-diol (Kaftory, 1987;Fujiwara, Tanaka, Tanaka & Toda, 1989;Toda, Tanaka & Mak, 1989;Fujiwara, Nanba, Hamada, Toda & Tanaka, 1990). …”