Vinylogous Nucleophilic Substitution Research Articles

Reaction of 2-perfluoroalkanoylcyclohexane-1,3-diones and 3-chloro-2-perfluoroalkanoylcyclohex-2-ene-1-ones with amines

Reactions of 2-perfluoroalkanoylcyclohexane-1,3-diones with primary and secondary amines involved acid cleavage of the substrate with formation of the corresponding 3-aminocyclohex-2-en-1-ones. Vinylogous nucleophilic substitution in 3-chloro-2-perfluoroalkanoylcyclohex-2-ene-1-ones with amines led to the formation of 3-amino-2-perfluoroalkanoylcyclohex-2-ene-1-ones.

Vinylogous Nucleophilic Substitution: A Route to New Polymers

Abstract The basic chemistry underlying the successful synthesis of poly-(enaminoesters) by vinylogous nucleophilic substitution is examined. It is concluded that a new mechanism must be operative. A Michael addition followed by elimination of a volatile fragment is proposed.

Polymers containing hydrogen bonding rings. Synthesis and thermal properties of poly(enamine‐ketones)

AbstractThe synthetic route to poly(enamine‐ketones) by vinylogous nucleophilic substitution of aromatic bis(1,3‐diketones) with aromatic and aliphatic diamines is described. The preparation of aromatic bis(1,3‐diketones), their polymerization, and thermal properties of the polymers are presented in detail. The polymers exhibited anisotropic melts and representative model compounds were shown to be thermotropic liquid crystals.

Synthesis of poly(oxovinyl sulfide)s by vinylogous nucleophilic substitution polymerizations of bis(3‐chloroacryloyl) derivatives of benzene with 4, 4′‐oxydibenzenethiol

AbstractPoly(oxovinyl sulfide)s 3 were prepared by vinylogous nucleophilic substitution polymerization of bis(3‐chloroacryloyl) derivatives of benzenes (1a and 1b) with 4,4′‐oxydibenzenethiol (2). The synthesis involves solution polycondensation and two‐phase polycondensation with phase transfer catalysts. Polymers having inherent viscosities in the range of 0,2–0,7 dl·g−1 were obtained quantitatively by both methods. They are soluble in concentrated sulfuric acid, dichloroacetic acid, and m‐cresol, and practically insoluble in polar aprotic solvents and common organic solvents. Thermogravimetric studies in both air and nitrogen atmospheres indicated that the decomposition temperatures for 10% weight loss of the polymers were about 400°C.

ビニログ的求核置換重合による新しい縮合系高分子の合成

This article describes the syntheses of various types of novel condensation polymers by vinylogous nucleophilic substitution polymerization and related aromatic nucleophilic substitution polymerization. After a brief introduction of the chemistry of vinylogous nucleophilic substitution, the polymerizations of open-chain and ring-containing activated vinyl monomers, as well as activated aromatic monomers, with various nucleophiles such as diamines, bisphenols, and dithiols are presented.

Synthesis of Polyenamines with Pendant Hydroxyl Groups by Ring-Opening Polyaddition of 5,5′-Oxalylbis(3,4-dihydro-2H-pyran) with Diamines

A new class of polyenamines with pendant hydroxyl groups was synthesized by the ring-opening polyaddition of 5,5′-oxalylbisi(3,4-dihydro-2H-pyran) with diamines through vinyl-ogous nucleophilic substitution. Solution polymerization carried out in alcoholic solvents such as m-cresol at room temperature afforded polymers having inherent viscosities of 0.1–0.27 in quantitative yields. The hydroxyl-containing polyenamines were soluble in a limited number of solvents and had low softening temperatures, below 200°C.

Synthesis of polyenamines by vinylogous nucleophilic substitution polymerization of 1,6‐diethoxy‐1,5‐hexadiene‐3,4‐dione with diamines

AbstractNovel polyenamines with inherent viscosities in the 0.2–1.1 range were synthesized by the vinylogous, nucleophilic substitution polymerization of 1,6‐diethoxy‐1,5‐hexadiene‐3,4‐dione with aromatic and aliphatic diamines in polar aprotic solvents at room temperature. The most effective polymerization medium was hexamethylphosphoramide for preparing high‐molecular‐weight polymers from aromatic diamines. The dilute solutions showed a marked decrease in viscosity with time. The aromatic polyenamines began to lose weight around 200°C under thermogravimetric analysis in air and nitrogen.

Synthesis of polyamide‐pyrazolones from 2,2′‐disubstituted bis(4‐ethoxymethylene‐5‐oxazolone) and aromatic dihydrazines

AbstractA new class of polyamide‐pyrazolones was synthesized by the vinylogous nucleophilic substitution polymerization, which was followed by rearrangement, from 2,2′‐p‐phenylenebis(4‐ethoxymethylene‐5‐oxazolone) and aromatic dihydrazines. Solution polymerization was carried out in polar aprotic solvents under mild conditions to yield polymers having inherent viscosities in the range of 0.5–1.2 quantitatively. The polymer derived from bis(4‐hydrazinophenyl) sulfone was readily soluble in strongly polar solvents, while that from bis(4‐hydrazinophenyl)methane was partially soluble or swelled in these solvents. The polyamide‐pyrazolones which are presumed to contain some intermediate oxazolone structure showed a low level of thermal stability.

Synthesis of polyarylamines by vinylogous nucleophilic substitution polymerization of bis(4‐chloro‐3‐nitrophenyl) sulfone with diamines

AbstractA series of new polyarylamines was prepared by the vinylogous nuclephilic substitution polymerization of bis(4‐chloro‐3‐nitrophenyl) sulfone with both aromatic and aliphatic diamines. The synthesis involves the solution polycondensation in a polar aprotic solvent at elevated temperatures, a tertiary amine being used as an acid acceptor. Of these solvents, dimethyl sulfoxide and N‐methyl‐2‐pyrrolidone were the most effective for the preparation of high molecular weight polymers. The polyarylamines having inherent viscosities in the range of 0.1–0.5 were all amorphous and highly soluble in polar aprotic solvents. Thermogravimetric analysis under both air and nitrogen atmospheres indicated that rapid decomposition began above 300°C for the polyarylamines from aromatic diamines.

Synthesis of polyenamines by vinylogous nucleophilic substitution polymerization of 2,2′‐disubstituted bis(4‐ethoxymethylene‐5‐oxazolone) with diamines

AbstractA new class of polyenamines was synthesized by the vinylogous nucleophilic substitution polymerization of 2,2′‐p‐phenylenebis(4‐ethoxymethylene‐5‐oxazolone) with diamines in polar aprotic solvents under very mild conditions. The polymers derived from aliphatic diamines were soluble in these solvents and had inherent viscosities in the range of 0.3–0.9. The dilute solutions showed marked decrease in viscosity with time, presumably due to hydrolytic chain scission of the enamine structures in the polymer backbone. The polymers exhibited no melting temperature, and onset of breakdown under thermogravimetric analysis in a nitrogen atmosphere occurred at 250–300°C.