Perhydrotriphenylene

Variable-temperature ESR studies have revealed large magnetic bistabilities in thiadiazole-fused 1,3,2-dithiazolyl 32 <2001SM1767, 2001MI451, 2002MI064434>, the thiadiazolopyrazine-fused 1,3,2-dithiazolyl 34, but not with the benzothiadiazolo-fused 1,3,2-dithiazolyl 33 <2004JA8256>. ESR studies have also been performed on inclusion crystals of the bicyclic [ 1,2,5]thiadiazolo[3,4-z/][ 1,3,2]dithiazol-2-yl 32 in channels of perhydrotriphenylene and tris(o-phenylenedioxy)cyclotriphosphazene <2002MI432>. 

The polymerization of trans-1,3-pentadiene, 149, in a chiral channel inclusion complex with enantiomerically pure perhydrotriphenylene affords an optically active polymer, 150 (236). Asymmetric polymerization of this monomer guest occurs also in deoxycholic acid inclusion complexes (237). 

Among other hosts108 for inclusion and/or clathrate compounds are deoxycholic acid,101 cholic acid,102 small ring compounds such as 29,103 perhydrotriphenylene,104 and the compound 30, which has been called a carcerand.105... 

Perhydrotriphenylene —6 but varies n-paraffins, linear ethers, esters... 

Perhydrotriphenylene (PHTP) is a chiral molecule. The equatorial isomer of PHTP gives rise to a wide variety of inclusion compounds with different kinds of molecules, ranging from those with a nearly spherical or planar... 

When butadiene and 2,3-dimethylbutadiene are included in the channels of urea and thiourea, respectively, 1,4 addition invariably results to yield polymers with chemical and stereo regularities (Scheme 39). Note that addition in the 1,2 fashion is prevented sterically by the narrow channel. Similarly, high selectivity was obtained when butadiene, vinyl chloride, and styrenes were polymerized in the channels of cyclophosphazenes. Syndiotac-tic polymer alone is obtained from vinyl chloride included in urea channels this is apparently the first example of inclusion polymerization of a vinyl polymer in which control is exerted over the steric configuration of the developing tetrahedral carbon atom (Scheme 39). Highly isotactic polymer is obtained from 1,3-pentadiene when it is included in a perhydrotriphenylene matrix (Scheme 39). Note that addition could occur at either end (i.e., Q to... 

BINAP, 127, 171, 191, 194, 196 olefin reaction, 126, 167, 169, 191 organic halides, 191 Pancreatic lipase inhibitors, 357 Pantoyl lactone, 56, 59 para-hydrogen, 53 Peptides, matrix structure, 350 Perhydrotriphenylene, crystal lattice, 347 Pericyclic reactions, 212 chiral metal complexes, 212 Claisen rearrangement, 222 Diels-Alder, 212, 291 ene reaction, 222, 291 olefin dihydroxylation, 150 Phase-transfer reactions asymmetric catalysis, 333... 

Fig. 15. Macrocyclic and oligocydic lattice hosts perhydrotriphenylene (32) a cyclotriphosphazene (33) cyclotriveratrylene (34) tri-o-thymotide (35).

Chiral solid matrices are used for asymmetric synthesis polymerization of 1,3-dienes (inclusion polymerization), although the matrix reaction is not exactly a catalytic synthesis [40,41]. (R)-trans-anti-trans-anti-trans-Perhydrotriphenylene (13) [42,43], deoxyapocholic acid (14) [44,45], and apocholic acid (15) [46,47] are known as effective matrices for the... 

Konig, 0., Burgi, H. B., Armbmster, T., Hulliger, J., Weber, T., A study in crystal engineering Structure, crystal growth, and physical properties of a polar perhydrotriphenylene inclusion compound. J. Am. Chem. Soc. 1997, 119, 10632-10640. 

All-trans-perhydrotriphenylene (PHTP) (cf. insert in Figure 14) is the product of exhaustive hydrogenation of triphenylene. It belongs to one of ten stereoisomers of PHTP. The chiral compound of high rotational symmetry (D3 — C3 -h 3 C2) forms inclusion complexes. The stereoselective polymerization via 7-radiation of the prochiral diolelin 1,3-pentadiene within the chiral nano channels of (.R)-(-)-all-trans-PHTP led to an optically active 1,4-trans-isotactic polymer (Nattaand Farina, 1976) (cf. Figure 13). 

Farina, M. and Audisio, G. (1970) Stereochemistry of perhydrotriphenylene II. Absolute rotation and configuration of optically active anti-trans-anti-trans-anti-trans-perhydrotriphenylene, Tetrahedron 26, 1839-1844. 

Schiirch, S., Saxer, A., Claude, S., Tabacchi, R., Trusch, B., and Hulliger, J. (2001) Semi-preparative gas chromatographic separation of ah-trans-perhydrotriphenylene enantiomers on a chiral cyclodextrin stationary phase, J. Chromatogr. A 905, 175-182. 

Crystalline inclusion complexes (IC s) have been also formed between polymers and another small-molecules, host clathrated provide a unique environment for observing the solid - state behavior of isolated polymer chains. In their IC s with small-molecule, host clathrates, such as urea (U) [1] and perhydrotriphenylene (PHTP) [57], the included polymer chains are confined to occupy narrow channels (ca. 5.4 A in diameter) where they are extended and separated from neighboring chains by the channel walls, which are composed exclusively of the host clathrate, crystalline matrix. Choi et al. [58] have been studied the behavior of isolated, extended polymer chains included in their IC s with U and PHTP by a combination of molecular modeling [59,60] and experimental observations in an effort to determine their conformations and mobilities in these well-defined, containing environments. 

The DE approach was shown [102] to be successful in establishing a good approximation of the disordered crystal structure of the perhydrotriphenylene/1-(4-nitrophenyl)piperazine inclusion compound [102], despite the considerable computational effort required for the simulation of diffuse scattering data. This application is also notable for the use of parallel computing concepts to exploit the implicit parallelism of evolutionary algorithms in order to increase computational efficiency. 

Various supramolecular crystals have been reported. Several examples of unit molecules used to build supramolecular crystals are summarized in Fig. 4.10. Perhydrotriphenylene (a), 9,9 -bianthryl (b), cyclophosphazene (c)... 

The most common hosts for inclusion polymerization are urea, thiourea, perhydrotriphenylene (PHTP), deoxycholic acid (DCA), apocholic acid (ACA) and tris(o-phenylenedioxy)cyclotriphosphazene (TPP)(Fig. 2). They have the common feature of forming channel-like clathrates, but differ in many specific properties. For instance, urea and thiourea have a rigid structure in which the host molecules are connected by hydrogen bonds and possess a high selectivity towards the guests. In urea channels are rather narrow whereas in thiourea they are wider as a consequence, linear molecules include only in urea and branched or cyclic molecules in thiourea. On the contrary, chainnels existing in PHTP clathrates are very flexible and can accomodate linear, branched and cyclic molecules. 

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