Hypervalent iodine oxidation of benzil-α-arylimino oximes: an efficient synthesis of 2,3-diphenylquinoxaline-1-oxides

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…”

Oxidative cyclizations of oximes using hypervalent iodine reagents

“…The cyclization reactions of oximes using hypervalent iodine(III) reagents can proceed with various nucleophiles, such as alkenes, [73][74][75][76] alcohols, [77][78][79][80][81] or amines, 67,82 within the molecule to produce the respective cyclic compounds. For example, Aggarwal and co-workers have reported an efficient synthesis of 2,3-diphenylquinoxaline-1-oxides 56 from benzyl--arylimino oximes 55 using DIB (Scheme 17).…”

Efficient Synthesis of Quinoxaline Derivatives by Selective Modification of 3‐Chloro‐6‐fluoroquinoxalin‐2(1H)‐one 4‐Oxide

“…The antimalarial activity of all hitherto unknown compounds has been investigated. [12] In both procedures, the starting material first has to be prepared from the corresponding aniline derivative. Biologically active quinoxalines, N-oxides and N,N-dioxides.…”

“…The two synthetically most versatile approaches are the cyclization of o-nitroacetanilide derivatives in the presence of a base, [10] and the oxidative cyclization of benzil-α-imino oximes with lead tetraacetate [11] or phenyliodine diacetate. [12] In both procedures, the starting material first has to be prepared from the corresponding aniline derivative. Based on the previously reported synthesis of functionalized 3-chloroquinoxalin-2(1H)-one 4-oxides starting from 1,1,2-trichloro-2-nitroethene (TCNiE,9) and aniline derivatives as inexpensive precursors, we were able to access a diversity of differently substituted mono-N-oxidized quinoxalinones in a one-step reaction with yields up to 79 % (Scheme 1).…”

“…MS (EI, 70 eV): m/z (%) = 294 (3) [M] + , 227 (60) [M -OH] + , 243 (10), 228 (5), 212 (100), 196 (88), 180 (8), 167 (70), 152(20), 136(15), 123(12), 108(19). MS (EI, 70 eV): m/z (%) = 294 (3) [M] + , 227 (60) [M -OH] + , 243 (10), 228 (5), 212 (100), 196 (88), 180 (8), 167 (70), 152(20), 136(15), 123(12), 108(19).…”