MULTICOMPONENT REACTIONS (MCRS) ARE AN IMPORTANT CLASS OF CONVERGENT ORGANIC REACTIONS, IN WHICH THREE OR MORE STARTING MATERIALS REACT TO FORM A PRODUCT THAT CONTAINS ATOMS DERIVED FROM ALL STARTING MATERIALS AND OFTEN HAS A HIGH ATOM ECONOMY. BECAUSE OF EXISTENCE OF THIS IMPORTANT ABILITY, IN THESE DECADE RESEARCH ON THIS AREA HAS RAPIDLY GROWN.HERE IN WE WISH TO REPORT THE FOUR-COMPONENT REACTION OF 2-FORMYLBENZOIC acidS, Barbituric acid/THIOBarbituric acid, ISOCYANIDES AND MEOH/ETOH IN WHICH PROCEEDED TO GIVE NEW Barbituric acid AND THIOBarbituric acid DERIVATIVES IN HIGH YIELDS IN THE ABSENCE OF ANY CATALYST UNDER REFLUX CONDITION. THE STRUCTURE OF PRODUCTS WERE DEDUCED FROM THE IR, 1H NMR, AND 13C NMR SPECTROSCOPY ANALYSIS.

BACKGROUND: HETEROCYCLIC DERIVED AZO DYES ARE INTERESTED DUE TO MODIFIED DYING AND OPTICAL PROPERTIES RELATIVE TO AZO BENZENOID ANALOGS [1, 2]. IN ORDER TO IMPROVE THE OPTICAL AND DYING PROPERTIES OF AZO CHROMOPHORES, POLYMERIC DYES ARE SUITABLE DUE TO NON-LEACHING BEHAVIOR AND UNIFORM DISPERSION OF COLORANTS WITHOUT AGGREGATION [3]. IN THE PRESENT RESEARCH AN AZO Barbituric acid-BASED AROMATIC DIacid WAS SYNTHESIZED AND USED TO PREPARE AROMATIC POLYAMIDES VIA A DIRECT POLYCONDENSATION.METHODS: POLYMER SYNTHESIS: A MIXTURE OF MONOMER, DIAMINE (IIIDAA), TPP, CACL2, PY AND NMP WAS HEATED WITH STIRRING AT 100OC FOR 8H. THE OBTAINED SOLUTION WAS POURED AFTER COOLING INTO METHANOL AND THE PRECIPITATE (PAB) WAS FILTERED OFF, WASHED WITH METHANOL AND DRIED, D.T>350OC AND  H WAS 0.30 DL/G (H2SO4, 30OC)).RESULTS: THE MONOMER WAS SYNTHESIZED FROM 5-AMINOISOPHTHALIC acid AND Barbituric acid IN A 4-STEP REACTION PATHWAY. CHARACTERIZATION WAS PERFORMED BY TLC, IR, UV AND NMR. THE EFFECT OF PH IN AQUEOUS SOLUTION AND DIFFERENT ORGANIC SOLVENTS ON THE ABSORPTION SPECTRUM WAS INVESTIGATED. A SERIES OF AROMATIC POLYAMIDES WERE OBTAINED IN GOOD TO HIGH YIELD WITH THE INHERENT VISCOSITIES IN THE RANGE OF 0.2-0.51 DL/G WITH GOOD SOLUBILITYS IN APROTIC POLAR ORGANIC SOLVENTS. THE CHARACTERIZATION WAS PERFORMED BY FT-IR, TGA AND DSC. THE RESULTS SHOWED GOOD THERMAL STABILITY UP TO 340OC. FILM FORMING ABILITY OF THE PAS (8% IN DMAC AND NMP) SHOWED A SHATTERING AND BRITTLE NATURE.CONCLUSION: AN AZO-Barbituric BASED MONOMER WAS SYNTHESIZED AND SPECTROSCOPIC STUDIES SHOWED ITS AZOKETO FAVORITE FORM IN SOLID STATE AND HYDRAZO-KETO FORM IN SOLUTION. ITS POLYAMIDES SYNTHESIZED AND SHOWED GOOD SOLUBILITY IN POLAR SOLVENTS AND THERMAL STABILITY.

A LARGE NUMBER OF Barbituric acid DERIVATIVES HAVE BEEN WIDELY USED AS SEDATIVE, HYPNOTIC, ANTISPASMODIC, ANTICONVULSANT AND LOCAL ANAESTHETIC DRUGS AS WELL AS IN ANTITUMOR, ANTICANCER AND ANTIOSTEOPOROSIS TREATMENTS [1-5]. IN THIS RESEARCH, WE REPORT SYNTHESIS OF SOME NEW AZO DYES CONTAINIG OF BARBITORATE RINGS.4-AMINO HIPPURIC acid WAS DIAZOTISED AND COUPLED WITH BARBITORIC acid AND 2-THIOBARBITORIC acid. THEN, THE PRODUCT REACTED WITH AROMATIC ALDEHYDE, SODIUM ACETATE AND ACETIC ANHYDRIDE AND OXAZOLONE RING WAS FORMED.SOLVATOCHROMIC BEHAVIOR OF THESE DYES WERE STUDIED IN THE ETOH, DMSO AND DMF. THE STRUCTURES OF PRODUCTS WERE CONFIRMED BY FT-IR, 1H NMR, 13C NMR AND MASS SPECTRA.

USUALLY HOMOGENEOUS BASE CATALYSTS ARE USED FOR THIS KIND OF REACTION. HETEROGENEOUS CATALYSTS HAVE ALSO BEEN USED FOR THE KNOEVENAGEL REACTION THUS; THE REACTION HAS BEEN CATALYZED BY HETEROGENEOUS CATALYSTS BASED ON ALUMINA, SILICA, ZINC AND MAGNESIUM OXIDES, RESINS AND OTHER CATALYSTS WITH MORE OR LESS SUCCESS [13]. …

SOME QUINOLINE AND PYRIDINE BISBARBITURATES INVOLVING ANTICANCER EFFECT HAVE BEEN REPORTED BY NEUMANNET AL. AND APPEARED AS ENOLIC AND ZWITTERIONIC FORM [1]. BASED ON THESE CONCEPTS, WE HAVE DEVELOPED THE SYNTHESIS OF VARIOUS BIS (THIO) BARBITURATES IN THE PRESENCE OF DIFFERENT BASES. MANY OF THESE COMPOUNDS EXHIBIT AN INTRAMOLECULAR HYDROGEN BOND [2]. ...