Efficient Synthesis of the Functionalized Spiro[indoline‐3,4′‐pyridine] via Four‐component Reaction

Abstract

An efficient synthetic procedure for the functionalized spiro[indoline-3,4'-pyridine] was developed via the four-component reactions of arylamines, acetylenedicarboxylates, isatins and malononitrile with triethylamine as the base catalyst. The advantages of this reaction are using common starting material, mild reaction conditions, broad scope of reactants and operational simplicity.

Synthesis of functionalized spiro[indoline-3,4’-pyridines] and spiro[indoline-3,4’-pyridinones] via one-pot four-component reactions

“…The efficient formation of functionalized spiro[indole-3,4’-pyridines] via the four-component reaction prompted us to study the reaction scope further [25]. Another widely used electron-deficient alkyne reagent, methyl propiolate, was utilized to replace dimethyl acetylenedicarboxylate as one component.…”

“…General procedure for the synthesis of spiro[indoline-3,4’-pyridine] derivatives 1a–1p : In an analogous manner to our procedure published in [25], a solution of arylamine (2.0 mmol), methyl propiolate (2.0 mmol) in 5 mL ethanol was stirred at room temperature overnight. Then isatin (2.0 mmol), malononitrile (2.0 mmol) and triethylamine (0.4 mmol) were added.…”

“…Many domino reactions have been developed by trapping this kind of β - enamino ester with sequential adding of nucleophilic or electrophilic reagents to give versatile nitrogen-containing compounds and N,O -heterocycles [12–23]. Recently, Perumal and we have both developed an efficient synthetic procedure for functionalized spiro[indoline-3,4’-pyridines] by domino reactions of in situ generated β-enamino esters, isatin and malononitrile with triethylamine as the base catalyst [24–25]. A literature survey indicated that there has been an explosion of activity around the synthesis of spirooxindoles in the past years [26–31].…”

One‐pot Two‐Step Cycloaddition Reaction for Convenient Synthesis of Polycyclic Spirooxindole‐fused [1,3]Oxazines

“…[13][14][15][16][17][18][19][20][21][22][23][24][25][26][27] In the past few years, we have also developed several practical procedures for the synthesis of diverse spirooxindoles via multicomponent reactions by using isatins and its 3-methylene, 3-imino derivatives as the substrates. [28][29][30][31][32][33][34][35][36][37][38][39][40] Recently, we successfully found that spiro[indoline-3,1'-quinolizin]-2-ones, which were generated from the three-component reaction of substituted pyridine, acetylenedicarboxylate and 3-phenacylideneoxindoles, could undergo Diels-Alder reaction with the typical dienophiles such as maleic anhydride and N-phenylmaleimides. [41][42][43] Alternatively, spiro[3H-indole-3,2'-[2H,9aH-pyrido [2,1-b] [1,3]oxazine], which were formed from three-component reaction of the substituted pyridines, electron-deficient alkynes and isatins, also underwent Diels-Alder reaction with 3-phenacylideneoxindoles (eq.…”

Diastereoselective Synthesis of Functionalized Tetrahydropyrimidin‐2‐thiones via ZnCl2 Promoted One‐pot Reactions

“…[3][4][5] A number of domino and multicomponent reactions have been developed by using β-enaminones and β-enamino esters to react further with sequential adding nucleophilic or electrophilic reagents to give versatile heterocyclic systems. [11][12][13][14][15][16][17][18][19][20] Against this background and also in the context of our investigations to develop new domino reactions, herein we report the diastereoselective synthesis of functionalized tetrahydropyrimidin-2-thiones via ZnCl 2 promoted one-pot reactions of cyclic amine, methyl propiolate, aromatic aldehydes and thiourea. [11][12][13][14][15][16][17][18][19][20] Against this background and also in the context of our investigations to develop new domino reactions, herein we report the diastereoselective synthesis of functionalized tetrahydropyrimidin-2-thiones via ZnCl 2 promoted one-pot reactions of cyclic amine, methyl propiolate, aromatic aldehydes and thiourea.…”