Terphenyl moiety

Therefore structural units as the m-terphenyl moiety, which was used in the concave benzoic acids 38, would be useful if new functionalities could be placed in the 2 -position. In the case of the benzoic acid 33, the functional group (COOH) was incorporated by the reaction of the 2 -lithio compound 71 with CO2. But other electrophiles may also be used here [28]. Scheme 13 lists new m-terphenyls 72-75 whieh were obtained when electrophiles other than CO2 were used. Standard group transformations transferred these products into other 2 -substituted m-terphenyls 76-82 which are also listed in Scheme 13. 

Calix[4]arenes can be functionalized both at the phenolic OH groups (lower rim) and at the para positions of the phenol rings (upper rim).21 A special class of selectively functionalized calix[4]arenes comprises bridged calix[4]arenes in which two phenol rings are connected by a cap.22 An important subgroup of this class are the calixspherands in which a calix[4]arene is diametrically bridged with a rigid terphenyl moiety. 

Cnppedo- and cappedophanes are names coined by Hart et al. for systems accessible by sulfone pyrolysis, that possess an open ( cuppedo- , in 178,180, and 182) or closed ( cappedo- , in 184) molecular cavity [63]. The central phenyl ring in the m-terphenyl moiety adopts a position perpendicular to the outer, neighbouring phenyl rings, thus allowing introduction of substituents, which point into the center of the cavity, as exemplified in 182 and 184. 

The m-terphenyl moieties can first be linked at Ej and E2, then converted to bicyclic phanes, as shown in Scheme 14. In the final step, the outer rings of the two m-terphenyl moieties of tetrabromide 139 can also be linked by xylylene dithiols. Related compounds such as 141 have recently been prepared [30] as potential amino acid receptors. 

The solid state structure of 120 (Fig. 6) shows that one of the two dithiaketone arms (from S6 to Cll) that connect the outer rings of the m-terphenyl moiety is disordered. The structure was solved and refined (R = 0.041) with an occupancy... 

Figure 4.19 Fluorinated and nonfluorinated polyamides containing terphenyl moiety [20].

PPS combining biphenyl or terphenyl moieties in the main chain are reported in the literature [103]. 

The contact times, ti/2, necessary to obtain half of the maximum equilibrium polarization in cross-polarization experiments using very short contact times have been determined at 298 K. At the frequencies involved, i.e. 10" -10 Hz, the methylene unit adjacent to the terphenyl moiety has a rigid-lattice behaviour, whereas the next-nearest CH2 group undergoes oscillations on the valence cone of approximatey 20"" about one equilibrium conformation. The following CH2 group performs oscillations of large amplitude, or more likely jumps between two equilibrium conformations. 

The motions of the carbonyl group and terphenyl moiety have been studied by using the properties of the chemical shift anisotropy. Indeed, the chemical shift anisotropy can be partly or totally... 

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