Quinoline polymerization

Synonyms 1,2-Dihydro-2,2,4-trimethylquinoline homopolymer 1,2-Dihydro-2,2,4-trimethylquinoline polymer Poly-(1,2-dihydro-2,2,4-trimethylquinoline) Polymerized 1,2-dihydro-2,4,4-trimethyl quinoline Polymerized 2,2,4-trimethyl-1,2-dihydroquinoline TDQP TMDHQ TMQ Trimethyidihydroquinoline polymer 2,2,4-Trimethyl-1,2-dihydro-quinoline, polymeric Classification Dihydroquinoline Empirical (C H, N) ... 

Quinolines Polymerized 2,2,4-trimethyl-1,2-dihydroquinoline (AgeRite Resin D) Slight to moderate G E F P F-P... 

Synthesis and Properties. Polyquinolines are formed by the step-growth polymerization of o-aminophenyl (aryl) ketone monomers and ketone monomers with alpha hydrogens (mosdy acetophenone derivatives). Both AA—BB and AB-type polyquinolines are known as well as a number of copolymers. Polyquinolines have often been prepared by the Friedlander reaction (88), which involves either an acid- or a base-catalyzed condensation of an (9-amino aromatic aldehyde or ketone with a ketomethylene compound, producing quinoline. Surveys of monomers and their syntheses and properties have beenpubhshed (89—91). 

The wide variety of ketomethylene and amino ketone monomers that could be synthesized, and the abiUty of the quinoline-forming reaction to generate high molar mass polymers under relatively mild conditions, allow the synthesis of a series of polyquinolines with a wide stmctural variety. Thus polyquinolines with a range of chain stiffness from a semirigid chain to rod-like macromolecules have been synthesized. Polyquinolines are most often prepared by solution polymerization of bis(i9-amino aryl ketone) and bis (ketomethylene) monomers, where R = H or C H, in y -cresol with di-y -cresyl phosphate at 135—140°C for a period of 24—48 h (92). 

Mechanistic studies on the formation of PPS from polymerization of copper(I) 4-bromobenzenethiolate in quinoline under inert atmosphere at 200°C have been pubUshed (91). PPS synthesized by this synthetic procedure is characterized by high molar mass at low conversions and esr signals consistent with a single-electron-transfer mechanism, the Sj l-type mechanism described earlier (22). 

A number of dihydroquinolines have been prepared by treating aniline derivatives with acetone or mesityl oxide in the presence of iodine. In these cases aromatization to the fully unsaturated quinoline would require the loss of methane, a process known as the Riehm quinoline synthesis. Such Skraup/Doebner-von Miller-type reactions are often low yielding due to large amounts of competing polymerization. For example, aniline 37 reacts with mesityl oxide to give dihydroquinolines 39, albeit in low yield. ... 

Quinolines substituted at the pyridine ring may be obtained by using a substituted a ,/3-unsaturated aldehyde or ketone instead of the glycerol as starting material. However often a large amount of the carbonyl component polymerizes under the reaction conditions. 

Hydroxy-containing polymers such as poly(methyl-methacrylate-co-hydroxyethyl methacrylate) [65,66] or secondary cellulose acetate [67,68] were used for this purpose. Vanadium (V) 8-hydroxy quinoline-hydroxy-ethyl methacrylate adduct, prepared by condensation of the latter with a VOQ2OH complex, is polymerized to... 

F Papadimitrakopoulos, DL Thomsen, and KA Higginson, Quinoline-Based Polymeric Metal Chelate Light-Emitting Diodes, Proceedings of the International Society for Optical Engineering, Vol. 3148, San Diego, 1997, pp. 170-177. 

Polyquinolines (PQ) are obtained by the Friedlander reaction of a bis-o-aminoaromatic aldehyde (or ketone) with an aromatic hisketomethylene reactant [Concilio et al., 2001 Stille, 1981]. The quinoline ring is formed hy a combination of an aldol condensation and imine formation (Eq. 2-221). Polymerization is carried out at 135°C in m-cresol with poly (phosphoric acid) as the catalyst. The reaction also proceeds under base catalysis, but there... 

The aluminum was determined spectrophotometrically using 8-hydroxy-quinoline in a known quantity of polymer obtained from the xylene solution and previously purified. The absence of titanium from the polymeric product, isolated in this fashion, was checked by conventional analytical methods. 

The rate is slower in basic aprotic amide solvents, and faster in acidic solvents such as / -cresol. In general, the imidization reaction has been shown to be catalyzed by acid (14,32,33). Thermal imidization of poly(amic acid)s is catalyzed by tertiary amines (34). High temperature solution polymerization in -cresol is often performed in the presence of high boiling tertiary amines such as quinoline as catalyst. Dialkylaminopyridines and other tertiary amines are effective catalysts in neutral solvents such as dichlorobenzene (35). Alkali metal and zinc salts of carboxylic acids (36) and salts of certain organophosphorus compounds (37) are also very efficient catalysts in one-step polycondensation of polyimides. 

Catalysts. Acrolein and methacrolein 1,4-addition polymerization is catalyzed by lithium complexes of quinoline. The pcracctic acid epoxidation of a wide range of alkenes is catalyzed by 8-hydroxyquinoline. 

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