Iodobenzene diacetate on alumina: Efficient synthesis of 1,3,4-oxadiazolyl-1,8-naphthyridines in solventless system using microwaves

Abstract

1‐(5‐Aryl‐[1,3,4]oxadiazol‐2‐ylmethyl)‐3‐(p‐methoxyphenyl)‐1H‐[1,8]naphthyridin‐2‐ones (5) were synthesized by the oxidative cyclization of [2‐oxo‐3‐(p‐methoxyphenyl)‐2H‐[1,8]naphthyridin‐1‐yl]acetic acid arylidene‐hydrazides (4) with alumina‐supported iodobenzene diacetate (IBD) in solvent‐free conditions under microwave irradiation. The products are obtained in good yields and in a state of high purity.

Chemistry of Polyvalent Iodine

“…Likewise, the preparation of benzopyrano- and furopyrano-2-isoxazoline derivatives from 2-allyloxybenzaldoximes by DIB oxidation,379 the synthesis of various N-substituted indole derivatives via BTI-mediated intramolecular cyclization of enamines,380 the synthesis of 2-substituted benzothiazoles via the oxidative cyclization of thiobenzamides,381 the preparation of 2,3-diphenylquinoxaline-1-oxide from benzil-α-arylimino oximes using DIB,382 the synthesis of 1-(5-aryl-[1,3,4]oxadiazol-2-ylmethyl)-3-(4-methoxyphenyl)-1 H -[1,8]naphthyridin-2-ones by oxidative cyclization of [2-oxo-3-(4-methoxyphenyl)-2 H -[1,8]naphthyridin-1-yl]acetic acid arylidenehydrazides with alumina-supported DIB under microwave irradiation,383 the synthesis of 2,5-disubstituted-1,3,4-oxadiazoles by via BTI-mediated oxidative cyclization of aldazines,384 the preparation of 2-substituted oxazolines from aldehydes and 2-amino alcohols using DIB as an oxidant,385 the synthesis of 3,4-bis(1-phenyl-3-arylpyrazolyl)-1,2,5-oxadiazole- N -oxides by the DIB oxidation of pyrazole-4-carboxaldehyde oximes,386 the synthesis of 2-arylbenzimidazoles from phenylenediamines and aldehydes via a one-step process using DIB as an oxidant,387 the DIB-mediated efficient synthesis of imidazoles from α-hydroxy ketones, aldehydes and ammonium acetate,388 the preparation of dihydrooxazole derivatives by DIB-promoted 1,3-dipolar cycloaddition reactions of phthalhydrazide,389 and the synthesis of seco -psymberin/irciniastatin A via a DIB-mediated cascade cyclization reaction 390. Very recently, Togo and Moroda have reported a DIB-mediated cyclization reaction of 2-aryl- N -methoxyethanesulfonamides using iodobenzene as a catalyst (5–10 mol%) and m -chloroperoxybenzoic acid as the stoichiometric oxidant 391…”

“…Similar DIB- or BTI-induced cyclizations of the appropriate amide or amine precursors have been used in numerous useful synthetic transformations, such as the synthesis of highly substituted pyrrolin-4-ones via BTI-mediated cyclization of enaminones, the synthesis of 2-substituted 4-bromopyrrolidines via DIB-induced intramolecular oxidative bromocyclization of homoallylic sulfonamides in the presence of KBr, the preparation of 2-( N -acylaminal)-substituted tetrahydropyrans by DIB-induced oxidative cyclization of hydroxy-substituted N -acyl enamines, the preparation of 1,2,4-thiadiazoles by the reaction of DIB or BTI with 1-monosubstituted thioureas, , the synthesis of azaspirocyclic synthetic intermediates via the BTI-induced nitrenium ion cyclizations, − the preparation of lactams and spiro-fused lactams from the reaction of N -acylaminophthalimides and BTI, the stereocontrolled preparation of highly substituted lactams and N -hydroxy lactams from appropriate hydroxamates and BTI, the synthesis of 1,2,4-triazolo[4,3- a ][1,8]naphthyridines using DIB-oxidation of 1,8-naphthyridin-2-ylhydrazones in the solid state, the synthesis of various substituted 1,2,4-triazolo[4,3- a ]pyrimidines by the DIB-oxidation of the appropriate 2,4-pyrimidinylhydrazones, − the preparation of thiazolo[2,3-c]-s-triazoles by the reaction of arenecarbaldehyde-4-arylthiazol-2-ylhydrazones with poly[(4-diacetoxyiodo)styrene], the synthesis of pyrrolidino[60]fullerene from the DIB-promoted reaction between C60 and amino acid esters, the synthesis of 1,3,4-oxadiazoles from acylhydrazones by BTI oxidation, − the synthesis of 1-aryl-4-methyl-1,2,4-triazolo[4,3- a ]quinoxalines from arenecarboxaldehyde-3-methyl-2-quinoxalinylhydrazones, , and the synthesis of 1-benzoyltetrahydroisoquinoline derivatives using polymer-supported BTI . Likewise, the preparation of benzopyrano- and furopyrano-2-isoxazoline derivatives from 2-allyloxybenzaldoximes by DIB oxidation, the synthesis of various N-substituted indole derivatives via BTI-mediated intramolecular cyclization of enamines, the synthesis of 2-substituted benzothiazoles via the oxidative cyclization of thiobenzamides, the preparation of 2,3-diphenylquinoxaline-1-oxide from benzil-α-arylimino oximes using DIB, the synthesis of 1-(5-aryl-[1,3,4]oxadiazol-2-ylmethyl)-3-(4-methoxyphenyl)-1 H -[1,8]naphthyridin-2-ones by oxidative cyclization of [2-oxo-3-(4-methoxyphenyl)-2 H -[1,8]naphthyridin-1-yl]acetic acid arylidenehydrazides with alumina-supported DIB under microwave irradiation, the synthesis of 2,5-disubstituted-1,3,4-oxadiazoles via BTI-mediated oxidative cyclization of aldazines, the preparation of 2-substituted oxazolines from aldehydes and 2-amino alcohols using DIB as an oxidant, the sy...…”

Chitosan as an eco-friendly heterogeneous catalyst for Michael type addition reactions. A simple and efficient route to pyridones and phthalazines

“…We believe that the initial step in this process involves benzaldehyde condensation with malononitrile to yield benzylidene-malononitrile, a reaction that has been reported to occur under mild conditions [18,19]. The benzylidene-malononitrile then adds to 26 to yield Michael adduct 27A that cyclizes to yield cyclic imine 27B, which serves as the precursor of 28.…”

Efficient synthesis of 1,2,4‐triazolo[4,3‐a][1,8]naphthyridines under microwave irradiation

“…Chloramine‐T (CAT) is a very versatile oxidizing agent and is of much importance in its synthetic utility [11, 12]. In view of this and in continuation of our interest in microwave‐assisted organic transformations on 1,8‐napthyridine derivatives [13–17], we report herein, a convenient, practical and efficient method for the synthesis of 1,2,4‐triazolo[4,3‐ a ][1,8] naphthyridines using CAT in methanol under microwave irradiation.…”