Cyclopolymerization synthesis

Cyclopent-2-en-l-one, 2-hydroxy-3-methyl-synthesis, 3, 693 Cyclopentenone, 4-methoxy-formation, 1, 423 Cyclopenthiazide as diuretic, 1, 174 Cyclopent[2,3-d]isoxazol-4-one structure, 6, 975 Cyclophane conformation, 2, 115 photoelectron spectroscopy, 2, 140 [2,2]Cyclophane conformation, 2, 115 Cyclophanes nomenclature, 1, 27 Cyclophosphamide as pharmaceutical, 1, 157 reviews, 1, 496 Cyclopiloselloidin synthesis, 3, 743 Cyclopolymerization heterocycle-forming, 1, 292-293 6H-Cyclopropa[5a,6a]pyrazolo[l,5-a]pyrimidine pyrazoles from, 5, 285 Cydopropabenzopyran synthesis, 3, 700 Cyclopropachromenes synthesis, 3, 671 Cyclopropa[c]dnnolines synthesis, 7, 597 Cyclopropanation by carbenes... 

The monomer synthesis and cyclopolymerization were carried out following the procedure of Butler et al. (21). The resulting polyimide was shown to possess primarily pyrrolidine rings as indicated by infrared spectroscopy (21). Initially, the reduction was carried out with LiAlH in tetrahydrofuran. 

The free radical cyclopolymerization of diallylammonium compounds leads to linear water-soluble polymers containing predominantly pyrroli-dinium rings as the structural unit of the polymer chain [14,15]. This well-established principle of polymer synthesis was used for the synthesis of the polycarbobetaines from their zwitterionic monomers (route (1), see above), which are summarized in Scheme 1. 

Synthesis of Macrocyclic Ring-Containing Polymers Via Cyclopolymerization and Cyclocopolymerization... 

The principle of cyclopolymerization has been applied to the synthesis of macrocyclic ether-containing polymers which may simulate the properties of crown ethers. l,2-Bis(ethenyloxy)benzene (a 1,7-diene) and l,2-bis(2-ethenyloxyethoxy)benzene (a 1,13-diene) are typical of the monomers synthesized. Homopolymerization of the 1,7-diene via radical and cationic initiation led to cyclopolymers of different ring sizes homopolymerization of the 1,13-diene led to cyclic polymer only via cationic initiation. Both monomer types were copolymerized with maleic anhydride to yield predominantly alternating copolymers having macro-cyclic ether-containing rings in the polymer backbone. 

Before the discussion on the fact that the radical initiators failed to cyclopolymerize St-C3 St, we need the close examination of examples for the synthesis of the [3.3]paracyclophane skeleton. Because, for the syntheses of strained cyclic compounds like [3.3]-paracyclophane, the properties of intermediates formed during reactions seem to affect the cyclization of open-chain starting materials. 

The synthesis and polymerization characteristics of 1,4-dimethylenecyclohexane are described. Cationic polymerization of this monomer yields relatively low molecular weight polymers containing appreciable amounts of endocyclic double bonds. In contrast to our earlier claim, 1,4-dimethylenecyclohexane does not seem to cyclopolymerize to a significant extent. 

This type of polymerization method has the potential to give more complex polymer structures with less defects than the normal practice of carrying out reactions on preformed polymers. Therefore we have continued with the synthesis and cyclopolymerization of new complex monomers. Most of the previously synthesized monomers were made by a one-step Mannich reaction using a diallylamine and either a phenol or an aromatic amine. This chapter describes the synthesis and attempted polymerization of a much wider variety of monomer structures. 

While ring-opening polymerization of camphorsultam was attempted futilely to prepare a new polymer containing a bicyclic structure and a new acidic sulfonamide group in the backbone [115b], radical cyclopolymerization was exploited in the synthesis of 193 nm alicyclic polymers (Fig. 79). Transannular polymerization to form polynortricyclene bearing tert-butyl ester was utilized in radical copolymerization with MA (Fig. 79) [275]. Radical cyclopolymer-... 

The cyclopolymerization of diethyl dipropargylmalonate by [(CF3)2MeCO]2-(ArN=)Mo=CH Bu-t (21a) in 1,2-dimethoxyethane at ambient temperature also proceeds in a living fashion to provide a conjugated polymer having both five- and six-membered rings (see Table 8). The living nature of this polymerization has also been demonstrated by the synthesis of a block copolymer with 2,3-dicarbomethoxynorbornadiene. 

The cyclopolymerization of dipropargyl monomers carrying an ionic nature is a facile synthesis method for self-doped conjugated ionic polymers. Various dipropargyl quarternary ammonium salts were polymerized to yield the unusual conjugated polymers. The potential counterions are ionically bound to the... 

Asymmetric synthesis cyclopolymerization of 1,5-pentadiene (261) was performed with an optically active metallocene catalyst. The polymer (262) obtained by (S)-ethylenebis(tet-rahydroindenyl)zirconium (S)-binaphtholate ([a] 435+1848°) in the presence of methyl aluminoxane (MAO) showed molecular rotation [(p] 4os-49.3°, and NMR analysis showed that the polymer had -68% tram structure. An optically active copolymer consisting of cyclic 262 units and linear units formed by 1,2-insertion shows LC phases. ... 

Several other synthetic methods are also in principle feasible. For example, for the preparation of H-H poly(methyl methacrylate) the cyclopolymerization of meth-acrylic acid derivatives if directed exclusively to the five-membered ring formation (42), and for the preparation of H-H polymers of olefins disubstituted on one carbon atom, the Wurtz synthesis has become feasible. (Eqn. 6,7.)... 

Coates, G W. Waymouth, R. M. Enantioselective cyclopolymerization of 1,5-hexadiene catalyzed by chiral zirconocenes a novel strategy for the synthesis of optically active polymers with chirality in the main chain. J. Am. Chem. Soc. 1993,115, 91-98. 

Ho, S. C. H. Wu, M. M. Xiong, Y. Novel cyclopolymerization polymers from nonconjugated dienes and 1-alkenes. PCT International Patent Application WO 95/06669 (Mobil Oil Corp.), March 9,1995. Hustad, P. D. Coates, G W. Insertion/isomerization polymerization of 1,5-hexadiene synthesis of functional propylene copolymers and block copolymers. J. Am. Chem. Soc. 2062,124, 11578-11579. Hustad, P. D. Tian, J. Coates, G. W. Mechanism of propylene insertion using bis(phenoxyimine)-based titanium catalysts an unusual secondary insertion of propylene in a group IV catalyst system. J. Am. Chem. Soc. 2002,124,3614-3621. 

Other chelating polymers related structurally to polyethylenimine and polyethyl-enimine have been derived from cyclopolymerized diallylamines. The structure and properties of these resins have been reviewed by Hodgkin. The attempted synthesis of novel linear poly(lV-alkylethylenimine)s, for metal complexation, by demethylation of ionene polymers has been described.The reaction (involving treatment with UAIH4) was successful only with ionene oligomers. 

---