Search of new luminophores with predetermined physicochemical and chemical properties ХVІ. N-arylmethylene- and N–hetarylmethylene- substituted for polyvinylamine

Abstract

Investigation of transformation of polyacrylamide (PAA) in the polyvinylamine (РVAm) the reaction of Hofmann and further transformation of NH₂-groups polymer by the Leuckart—Wallach reaction. The reliability of the transformation of PAA into PVAm is confirmed by the reaction of diazotization and acylation of the samples obtained by PVA and by the color reactions of the PVAm transformation products. The structure of PVAm is also confirmed by data from IR spectroscopy and pH-metric titration. The product obtained is a vinylamine copolymer (up to 80%), acrylamide and acrylic acid. Syntheses of N-arylmethylene- and N-hetarylmethylene substituted PVAm, is carried out by the reduction alkylating of NH₂-groups of РVAm by aromatic and heterocyclic aldehydes [5‑(4‑chlorophenyl)-2-(4-formylphenyl)oxazol-1,3, 5-(4-methoxyphenyl)-2-(4-formylphenyl)oxazol-1,3, 5‑(4‑methylphenyl)-2-(5-formylfuryl-2)oxazol-1,3, 5-(4-methoxyphenyl)-2-(5-formylfuryl-2)oxazol-1,3, 3,5-diphenyl-1-(4-formylphenyl)-2-pyrazoline, pyrene-3-aldehyde, possessing luminescence, in presence formic acid. The indicated derivatives of PVAm are got also by successive formation with NH₂-groups of elementary links of grounds of Schiff and reduction of them NaBH₄. The derivatives of PVAm containing N-arylmethylene and N‑hetarylmethylene groups [...–CH₂−CH(NH−CH₂−Ar) – ... and ... –CH₂−CH(NH−CH₂−Het) – ...), respectively], low-grade in water, nonpolar organic, partially soluble in polar solvents and readily soluble in acid solutions.The got standards of modified PVAm, containing elementary links of …–СН₂−СН(NH−CH₂−Ar)–… and ...–СН₂−СН(NH−CH₂−Het)–..., luminesce both in the hard state and in solutions. IR-specta (hard state) РVAm and modified foods is studied, spectrums of absorption and luminescence of N-arylmethylene- and N‑hetarylmethylene substituted for PVAm, (in solutions of the mixed solvent is ethyl acetate - formic acid). The fluorescence maxima of PVAm derivatives are shifted to the short-wave region in comparison with similar solutions for initial aldehydes due to the reduction of the chromophore chain through the replacement of the aldehyde group with methylene.