Alum [KAl(SO4)2•12H2O] catalyzed microwave assisted synthesis of 5-arylidine-2-(methylthio)-thiazolone derivatives in water

Abstract

An efficient and environmentally benign method has been developed for the synthesis of 5arylidine-2-(methylthio)-thiazolones derivatives using Alum [KAl(SO4)2•12H2O] catalyst and triethyl amine in water under microwave irradiation. This green transformation generated one C-S and one CC bond, condensation and S-methylation. Notable advantages for the present protocol include, short reaction time, cleaner reaction profile and easy isolation of product by microwave irradiation technique using green catalyst and solvent.

Novel 3,4-Dihydroxyphenyl-Thiazole-Coumarin Hybrid Compounds: Synthesis, In Silico and In Vitro Evaluation of Their Antioxidant Activity

“…All intermediate compounds 2a – g and 3a – g were previously reported in the literature by other research groups [ 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ]. All final products 4a – g have not been previously reported in the literature.…”

“…This protocol represents a slight adaptation of a previously reported method [ 23 ]. All intermediate compounds 3a – g were previously reported [ 29 , 30 , 31 , 32 , 33 , 34 ].…”

“…(E)- 2-(1-(8-ethoxy-2-oxo-2 H- chromen-3-yl)ethylidene)hydrazinecarbothioamide ( 3c ): yellow crystals; mp = 221 °C (lit. 216–222 °C [ 31 ]); yield = 26.01%; FTIR (KBr) ν max (cm −1 ): 3411.94 (N-H), 1720.19 (C=O), 1613.16 (C=C), 1513.36 (C=N), 1471.90 (C-N), 1278.09 (C-O ether), 1239.04 (C-O ester); ESI + -MS: m / z = 306.1 ([M+H] + ).…”

Novel 3,4-Dihydroxyphenyl-Thiazole-Coumarin Hybrid Compounds: Synthesis, In Silico and In Vitro Evaluation of Their Antioxidant Activity

“…All intermediate compounds 2a – g and 3a – g were previously reported in the literature by other research groups [ 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ]. All final products 4a – g have not been previously reported in the literature.…”

“…This protocol represents a slight adaptation of a previously reported method [ 23 ]. All intermediate compounds 3a – g were previously reported [ 29 , 30 , 31 , 32 , 33 , 34 ].…”

“…(E)- 2-(1-(8-ethoxy-2-oxo-2 H- chromen-3-yl)ethylidene)hydrazinecarbothioamide ( 3c ): yellow crystals; mp = 221 °C (lit. 216–222 °C [ 31 ]); yield = 26.01%; FTIR (KBr) ν max (cm −1 ): 3411.94 (N-H), 1720.19 (C=O), 1613.16 (C=C), 1513.36 (C=N), 1471.90 (C-N), 1278.09 (C-O ether), 1239.04 (C-O ester); ESI + -MS: m / z = 306.1 ([M+H] + ).…”

Design, Synthesis, and Fungicidal Activity of a New Class of Thiadiazolylpyrimidine Carboxamide Derivatives Against R. solani Kuhn

“…Procedure for Synthesis of Amine Intermediates 3(a-r) [19] Equal quantities of thiosemicarbazide [1] (0.1 mole) and aromatic carboxylic acid [2] (0.1 mole) were combined with 20 mL of POCl 3 . The resulting mixture underwent reflux at 80 • C for 2 h, followed by the addition of 100 mL of water under cooling.…”

Coumarin Derivatives: Microwave Synthesis and Biological Properties—A Review

“…In 2015, Chavan et al [32] have prepared a synthesis of substituted comarins 10 in best yields up to 98% (72%-98%) by Pechmann condensation of phenols and solvent without βketoesters catalyzed by Zn[(l)-proline] 2 as organometallic catalysts by microwave irradiation (Scheme 10). Jadhav's et al [33] developed another multicomponent approach in 2015 for the combinatorial microwave-assisted synthesis of various pyrazolone derivatives conjugated to coumarin 11. Using alum [KAl(SO 4 ) 2 •12H 2 O] as the catalytic system and polyethylene glycol as the reaction medium.…”

Novel 3,4-Dihydroxyphenyl-Thiazole-Coumarin Hybrid Compounds: Synthesis, In Silico and In Vitro Evaluation of Their Antioxidant Activity

“…All intermediate compounds 2a – g and 3a – g were previously reported in the literature by other research groups [ 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ]. All final products 4a – g have not been previously reported in the literature.…”

“…This protocol represents a slight adaptation of a previously reported method [ 23 ]. All intermediate compounds 3a – g were previously reported [ 29 , 30 , 31 , 32 , 33 , 34 ].…”

“…(E)- 2-(1-(8-ethoxy-2-oxo-2 H- chromen-3-yl)ethylidene)hydrazinecarbothioamide ( 3c ): yellow crystals; mp = 221 °C (lit. 216–222 °C [ 31 ]); yield = 26.01%; FTIR (KBr) ν max (cm −1 ): 3411.94 (N-H), 1720.19 (C=O), 1613.16 (C=C), 1513.36 (C=N), 1471.90 (C-N), 1278.09 (C-O ether), 1239.04 (C-O ester); ESI + -MS: m / z = 306.1 ([M+H] + ).…”

Design, Synthesis, and Fungicidal Activity of a New Class of Thiadiazolylpyrimidine Carboxamide Derivatives Against R. solani Kuhn

“…Procedure for Synthesis of Amine Intermediates 3(a-r) [19] Equal quantities of thiosemicarbazide [1] (0.1 mole) and aromatic carboxylic acid [2] (0.1 mole) were combined with 20 mL of POCl 3 . The resulting mixture underwent reflux at 80 • C for 2 h, followed by the addition of 100 mL of water under cooling.…”

Coumarin Derivatives: Microwave Synthesis and Biological Properties—A Review

“…In 2015, Chavan et al [32] have prepared a synthesis of substituted comarins 10 in best yields up to 98% (72%-98%) by Pechmann condensation of phenols and solvent without βketoesters catalyzed by Zn[(l)-proline] 2 as organometallic catalysts by microwave irradiation (Scheme 10). Jadhav's et al [33] developed another multicomponent approach in 2015 for the combinatorial microwave-assisted synthesis of various pyrazolone derivatives conjugated to coumarin 11. Using alum [KAl(SO 4 ) 2 •12H 2 O] as the catalytic system and polyethylene glycol as the reaction medium.…”

Novel 3,4-Dihydroxyphenyl-Thiazole-Coumarin Hybrid Compounds: Synthesis, In Silico and In Vitro Evaluation of Their Antioxidant Activity

“…All intermediate compounds 2a – g and 3a – g were previously reported in the literature by other research groups [ 23 , 24 , 25 , 26 , 27 , 28 , 29 , 30 , 31 , 32 , 33 , 34 ]. All final products 4a – g have not been previously reported in the literature.…”

“…This protocol represents a slight adaptation of a previously reported method [ 23 ]. All intermediate compounds 3a – g were previously reported [ 29 , 30 , 31 , 32 , 33 , 34 ].…”

“…(E)- 2-(1-(8-ethoxy-2-oxo-2 H- chromen-3-yl)ethylidene)hydrazinecarbothioamide ( 3c ): yellow crystals; mp = 221 °C (lit. 216–222 °C [ 31 ]); yield = 26.01%; FTIR (KBr) ν max (cm −1 ): 3411.94 (N-H), 1720.19 (C=O), 1613.16 (C=C), 1513.36 (C=N), 1471.90 (C-N), 1278.09 (C-O ether), 1239.04 (C-O ester); ESI + -MS: m / z = 306.1 ([M+H] + ).…”

Design, Synthesis, and Fungicidal Activity of a New Class of Thiadiazolylpyrimidine Carboxamide Derivatives Against R. solani Kuhn

“…Procedure for Synthesis of Amine Intermediates 3(a-r) [19] Equal quantities of thiosemicarbazide [1] (0.1 mole) and aromatic carboxylic acid [2] (0.1 mole) were combined with 20 mL of POCl 3 . The resulting mixture underwent reflux at 80 • C for 2 h, followed by the addition of 100 mL of water under cooling.…”

Coumarin Derivatives: Microwave Synthesis and Biological Properties—A Review

“…In 2015, Chavan et al [32] have prepared a synthesis of substituted comarins 10 in best yields up to 98% (72%-98%) by Pechmann condensation of phenols and solvent without βketoesters catalyzed by Zn[(l)-proline] 2 as organometallic catalysts by microwave irradiation (Scheme 10). Jadhav's et al [33] developed another multicomponent approach in 2015 for the combinatorial microwave-assisted synthesis of various pyrazolone derivatives conjugated to coumarin 11. Using alum [KAl(SO 4 ) 2 •12H 2 O] as the catalytic system and polyethylene glycol as the reaction medium.…”