Spirobisindanes

However, it is necessary to determine precisely the orientation of the dipole moments, and to ensure that the observed CD is not the resultant from a mixture of con formers. Moreover, even with a correct choice of the dipoles, there are often shortcomings. For instance, studies of l,l -spirobisindanes have shown substantial discrepancies between the theoretical and experimental results for several products of known configuration 27). It has been shown that the signs of the bands stand in direct relation to the configuration of the spiro-atoms, which means that the optical activity is really governed by the coupling mechanism including other types of interaction. 

A decisive breakthrough to a T range above 230°C was achieved with a polycarbonate based on spirobisindan (SBI-PC, (8)) (203) or 3,3,5-trimethylcyclohexane (TMC-PC, (7) wherein the cyclohexane ring bears three methyl groups) (204). 

S.S -Tetrahydroxy-S -tetramethyl spirobisindane (TTSBI) was depro-tonated with f-BuOK and polycondensed with di(ethylene glycol) tosylate or tri(ethylene glycol) tosylate as shown in Fig. 46. At concentrations of 0.1 or 0.2 mol/L no cross-linking was observed and multicyclic polyethers were isolated in high yields (up to 99%). The formed polymer was an amorphous character with two glass-transition temperatures [151]. 

Highly rigid and contorted aromatic spirobisindane-based linkers were shown to ensure a space-inefficient packing of phthalocyanine macrocycles, giving polymer networks [269] with gratifyingly high surface areas (500-1000 m /g) and interconnected nanopores of diameters in the range 0.6—0.8 nm. 

Thomas S, Pinnau I, Du N et al (2009) Hydrocarbon/hydrogen mixed-gas permeation properties of PIM-1, an amorphous microporous spirobisindane polymer. J Membr Sd 338 1 ... 

S. Thomas, I. Pinnau, N. Du, M. D. Guiver, Pure- and mixed-gas permeation properties of a microporous spirobisindane-based ladder polymer (PIM-1), J. Membr. ScL, 333, 125-131 (2009). 

C. L. Staiger, S. J. Pas, A. J. Flill, C. J. Cornelius, Gas separation, free volume distribution, and physical aging of a highly microporous spirobisindane polymer, Chem. Mater, 20, 2606-2608 (2008). 

By manipulating the number of aromatic ortAo-dihalide groups and catechols in the monomers, a PIM can be prepared either as an insoluble or soluble polymer network. For instance, a soluble PIM (PIM-1) is prepared from the reaction between 5,5, 6,6 -tetrahydro3gr-3,3,3, 3 -tetra-methyl-l,l -spirobisindane and tetrafluoroterephthalonitrile. On the other hand, HATN-network PIM is synthesized by the reaction between the readily available spiro-cyclic bis(catechol) monomer and hexachlorohexa-azatrinaphthylene. ... 

Fluoro-monomer 1,4-dicyanotetrafluorobenzene (DTFB) and a tetrahydrojy monomer 5,5, 6,6 -tetrahydro y-3,3,3, 3 -tetramethyl-l,10-spirobisindane (TTSBI) participate and polymerise in one step to form soluble PIM-1 and PIMl-COl-40 ° (Figure 5.1). 

Materials 3-Hydroxy-, 3,5-dihydroxy, 3-amino- and 3,5-diaminobenzoic acid were gifts of BAYER AG (Leverkusen, FRG) and used without further purification. Bisphenol-P and bisaniline-P were purchased from Kennedy and Klim (Little Silver, N.J., USA). Piperazine, l,l,l-tris(4 -hydroxy-phenyl)ethane, phloretic acid tetrahydroxy spirobisindane were purchased from Aldrich Co. (Milwaukee, Wise., USA). All hydroxy acids and phenols were acetylated with an excess of acetic acid and a catalytic amount of pyridine in refluxing toluene. All silylations were conducted with chloro-trimethylsilane and triethylamine in refluxing toluene or dioxane. 

For the description of multicyclic polymers prepared by + />4 polycondensation, in principle, the same type of structural formulas and sum formulas can be used designed for 02 + 3 polycondensates (Formulas 12.5). However, two characteristic differences should be emphasized. First, depending on the stereochemical properties of the monomers even the bridged bicyclic monomers may yield isomers. As illustrated by scheme (a) in Formulas 12.6 (top), 64 monomers based on a tetravalent carbon such as pentaerythritol and its derivatives [e.g. (b) and (c) in Formulas 12.6] cannot form isomers. Yet, for the bicyclic monomers of tetrafunctional benzene derivatives two or three isomers may exist. The condensation of a non-symmetrical monomer, such as tetrahydroxy spirobisindane (TTSBI) with flexible 02 monomers may yield 8 isomeric dimers [18]. In other words, the exponential increase of the number of isomers with higher DPs is steeper than in the case of 02 + 3 polycondensates. The second characteristic difference is the fact, that in 02 + / 4 polycondensations monofuctional multicycles (analogous to those in Formulas 11.2 and 12.3, top) cannot be formed. Hence, only four not five different classes of multicycles exist ... 

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