Facile synthesis of functionalized tetrahydroquinolines via domino Povarov reactions of arylamines, methyl propiolate and aromatic aldehydes

Abstract

SummaryIn the presence of p-toluenesulfonic acid as catalyst the domino reaction of arylamines, methyl propiolates and aromatic aldehydes in ethanol proceeded smoothly to give polysubstituted 1,2,3,4-tetrahydroquinolines in moderate yields. The reaction is believed to involve the Povarov reaction of in situ generated β-enamino ester with the in situ formed aromatic imine.

Four-component reaction of cyclic amines, 2-aminobenzothiazole, aromatic aldehydes and acetylenedicarboxylate

“…Initially, we set out to investigate the reaction conditions by using piperidine to react with dimethyl acetylenedicarboxylate to give the expected β-enamino ester. It is interesting to find that the reaction of piperidine with acetylenedicarboxylate in ethanol at room temperature proceeded very quickly and could be finished to give the expected β-enamino ester in less than twenty minutes [ 27 ], while the reaction of normal primary arylamine with acetylenedicarboxylate or propiolate in ethanol at room temperature usually needed more than one day [ 28 ]. Thus we chose to employ a one-pot multicomponent reaction procedure to investigate our reaction.…”

Novel benzoquinoline derivatives via unpredicted condensation of ethyl propiolate and naphthylamines: Synthesis and topoisomerase inhibition activity

“…A carbonyl compound (aldehyde or ketone) [22][23][24][25] or a carboxyl compound (formic acid) 26 is required, whose carbonyl will represent the carbon in 4 position of the final quinoline nucleus. In our reaction the carbon in 4 position is the omega carbon of the second propiolate molecule, thus the further carbonyl compound is no longer needed to obtain the quinoline nucleus.…”

One‐pot Sequential Reaction for the Synthesis of Polysubstituted 3‐(3‐Nitro‐2‐phenylchroman‐4‐yl)‐3‐arylaminoacrylates

“…[17][18][19][20][21][22][23] We have also developed several domino reactions of the in situ formed β-enamino esters with nitrostyrene, [24] indole, [25] aromatic aldehydes, [26,27] α,β-unsaturated aldehydes, [28] arylidene malononitrile [29] and dicarbonyl compounds. [30,31] As a continuation of our approach toward the design of new domino synthetic procedures involving the use of β-enaminones and β-enamino esters as the key components, in this text we wish to report the one-pot sequential reactions of arylamines, methyl propiolate and 3-nitrochromenes for the efficient and diastereoselective synthesis of 3-(3-nitro-2-phenylchroman-4-yl)-3-arylaminoacrylates. : 3438, 3286, 3031, 2955, 1673, 1608, 1545, 1516, 1481, 1447, 1369, 1246, 1184, 1126, 1079, 1029, 961, 904, 848 …”