The reaction of (N‐isocyanimino) triphenylphosphorane with an electron‐poor α‐haloketone in the presence of aromatic carboxylic acids: A novel three‐component reaction for the synthesis of disubstituted 1,3,4‐oxadiazole derivatives

Abstract

Reactions of electron-poor α-haloketones with (N-isocyanimino)

Silica Gel Promotes Cascade Synthesis of 2-(Heteroaryl)acetamide Derivatives from Isocyanides, Dialkylamines, and Heteroarylcarbaldehydes

“…Its ease of workup and good yields makes it a useful addition to modern synthetic methodologies. [44][45][46][47][48][49][50][51][52][53][54][55] EXPERIMENTAL Starting materials and solvents were obtained from Merck (Germany) and Fluka (Switzerland) and were used without further purification. The methods used to follow the reactions were TLC and NMR.…”

Four-Component Preparation of Disubstituted 1,3,4-Oxadiazoles from (N-isocyanimino)triphenylphosphorane, Phenylacetylenecarboxylic Acid, Biacetyl and Primary Amines

“…16,17 In recent years, we have confirmed a one-pot method for the preparation of organophosphorus compounds. [18][19][20][21][22][23][24] As part of our ongoing program to develop efficient and robust methods for the preparation of heterocyclic compounds, [25][26][27][28][29][30][31][32][33][34][35][36][37][38] we wish to report the preparation of a new class disubstituted 1,3,4-oxadiazole derivatives 5a-j by a novel four-component condensation reaction of biacetyl (1), primary amine 2, (Nisocyanimino)triphenylphosphorane (4) and phenylacetylenecarboxylic acid (3) in excellent yields under neutral conditions (Scheme 1).…”

“…This intermediate may be attacked by conjugate base of the carboxylic acid to form 1:1:1 adduct 9. The intermediate 9 may undergo intramolecular aza-Wittig reaction [25][26][27][28][29][30][31][32][33][34][35][36][37][38][39] of iminophosphorane moiety with the ester carbonyl to afford the isolated sterically congested 1,3,4-oxadiazole derivatives 5 by removal of triphenylphosphine oxide (6) from intermediate 10.…”

Facile synthesis of indolizines using layered double hydroxides@poly(p‐phenylenediamine) as a catalyst with a green tool (neat technology)

“…The importance and strong demand for these heterocycles are because of their versatile photochemical features and biological activities . The activation of indolizine in many natural and synthetic pharmaceutically active compounds is considered as a special heterocyclic nucleus . Indolizines, as a vital class of N‐heterocycles with 10 π‐delocalized electrons, have received much attention due to their molecular structure and important biological activities .…”