Tetrakis(acetonitrile)copper(I) hexafluorophosphate catalyzed coumarin synthesis via pechmann condensation under solvent‐free condition

Abstract

Tetrakis(acetonitrile)copper(I) hexafluorophosphate (Cu(CH3CN)4PF6) is used as an efficient catalyst in the Pechmann condensation reaction of phenols with ethyl acetoacetate leading to the formation of coumarin derivatives in excellent yields under solvent free conditions at ambient temperature. The method is simple, solvent‐free and gives excellent yields in a short reaction time. J. Heterocyclic Chem.,(2011).

Recent Advances in Synthesis of 4-Arylcoumarins

“…Among them, CAN-catalyzed reactions under thermal and microwave conditions were also compared [ 31 ]. Cu(CH 3 CN) 4 PF 6 [ 33 ], and MnSO 4 [ 34 ] were also found to be efficient Lewis acids for the synthesis of coumarins (Entries 24,25). Moradi and Belali reported the use of molybdate sulfuric acid in the synthesis of 4-substituted coumarins via the Pechmann condensation (Entry 26) [ 35 ].…”

One-Pot Synthesis of Coumarins Unsubstituted on the Pyranic Nucleus Catalysed by a Wells–Dawson Heteropolyacid (H₆P₂W₁₈O₆₂)

“…The most common mehotd used for their synthesis is the Pechmann condensation, where phenol is reacted with a β-ketoester or acid under strongly acidic conditions [18][19][20]. The products synthesized by Pechmann condensation frequently have a substituent group on the pyranic heterocyclic nucleus [21][22][23]. The synthesis of coumarins unsubstituted on the pyranic heterocyclic nucleus poses a challenge in chemistry [24].…”

An Efficient Synthesis of Coumarin Derivatives Using a SBA-15 Supported Cobalt(II) Nanocatalyst

“…Pechmann condensations generally involve the reaction of phenolic compounds with a carboxylic acid or an ester containing a b-carbonyl group to generate an intermediate that undergoes dehydration to the final coumarin product. Several protocols have extensively covered the synthesis of coumarin derivatives via Pechmann condensation, mostly catalysed by homogeneous acidic catalysts including H 2 SO 4 , P 2 O 5 [10], trifluoroacetic acid [11] as well as different metal salts such as FeCl 3 , TiCl 4 , InCl 3 , ZrCl 4 [12][13][14][15], Bi(NO 3 ) 3 Á5(H 2 O) [16] and Cu(CH 3 CN) 4 PF 6 [17]. The use of homogeneous acid catalysts possesses inherent corrosion, separation, product isolation and purification and catalyst recycling issues, highly detrimental from the practical point of view.…”