α-Aminonitriles were synthesized via a one-pot three-component condensation of aldehydes, amines, and trimethylsilyl cyanide using silica-bonded N-propylpiperazine sulfamic acid （SBPPSA） as a recyclable solid acid ...α-Aminonitriles were synthesized via a one-pot three-component condensation of aldehydes, amines, and trimethylsilyl cyanide using silica-bonded N-propylpiperazine sulfamic acid （SBPPSA） as a recyclable solid acid at room temperature. SBPPSA showed much the same efficiency when used in consecutive reaction runs.展开更多
Silica‐bonded N‐propylpiperazine sodium n‐propionate(SBPPSP) was found to act as an efficient solid base for the preparation of a series of 4H‐benzo[b]pyran derivatives. SBPPSP was used as a recyclable heterogeneo...Silica‐bonded N‐propylpiperazine sodium n‐propionate(SBPPSP) was found to act as an efficient solid base for the preparation of a series of 4H‐benzo[b]pyran derivatives. SBPPSP was used as a recyclable heterogeneous solid base catalyst for the synthesis of 3,4‐dihydropyrano[c]chromenes, 2‐amino‐4H‐pyrans, 1,4‐dihydropyrano[2,3‐c]pyrazoles, and 2‐amino‐4H‐benzo[e]‐chromenes via the condensation reaction of dimedone, ethyl acetoacetate, 3‐methyl‐1‐phenyl‐1H‐pyrazol‐5(4H)‐ one, and α‐naphthol, respectively, with aromatic aldehydes and malononitrile in refluxing aqueous ethanol. The heterogeneous solid base showed similar efficiency when reused in consecutive reactions.展开更多
An efficient heterogeneous Pd catalytic system has been developed, based on immobilization of Pd nanoparticles (PNPs) on a silica-bonded N-propylpiperazine (SBNPP) substrate. The SBNPP substrate effectively stabilizes...An efficient heterogeneous Pd catalytic system has been developed, based on immobilization of Pd nanoparticles (PNPs) on a silica-bonded N-propylpiperazine (SBNPP) substrate. The SBNPP substrate effectively stabilizes the PNPs and improves their stability against aggregation. The catalytic activity of this catalyst was investigated in the cyanation of aryl halides with K4[Fe(CN)6 ] as the cyanide source. The catalyst could be recycled several times without appreciable loss of catalytic activity.展开更多
A simple and efficient procedure for the preparation of silica-bonded N-propylpiperazine sodium n-propionate(SBPPSP) by the hydrolysis of silica-bonded N-propylpiperazine methyl n-propionate(SBPPMP) in hydrochloric ac...A simple and efficient procedure for the preparation of silica-bonded N-propylpiperazine sodium n-propionate(SBPPSP) by the hydrolysis of silica-bonded N-propylpiperazine methyl n-propionate(SBPPMP) in hydrochloric acid(0.5 mol/L) followed by treatment with saturated sodium bicarbonate is described.The SBPPMP was obtained by the reaction of 3-silica-bonded N-propylpiperazine and methyl acrylate in methanol.SBPPSP was used as a recyclable basic catalyst for the synthesis of 3,4-dihydropyrano[c]chromenes by the reaction of aromatic aldehydes,malononitrile,and 4-hydroxycoumarin in aqueous ethanol(1:1 v/v) under reflux conditions.Biscoumarins were also obtained via condensation of aldehydes and 4-hydroxycoumarin in aqueous ethanol(1:1 v/v) under reflux conditions.The catalyst could be recycled several times without any additional treatment.展开更多
基金the Islamic Azad University Research Council for the partial support
文摘α-Aminonitriles were synthesized via a one-pot three-component condensation of aldehydes, amines, and trimethylsilyl cyanide using silica-bonded N-propylpiperazine sulfamic acid （SBPPSA） as a recyclable solid acid at room temperature. SBPPSA showed much the same efficiency when used in consecutive reaction runs.
文摘Silica‐bonded N‐propylpiperazine sodium n‐propionate(SBPPSP) was found to act as an efficient solid base for the preparation of a series of 4H‐benzo[b]pyran derivatives. SBPPSP was used as a recyclable heterogeneous solid base catalyst for the synthesis of 3,4‐dihydropyrano[c]chromenes, 2‐amino‐4H‐pyrans, 1,4‐dihydropyrano[2,3‐c]pyrazoles, and 2‐amino‐4H‐benzo[e]‐chromenes via the condensation reaction of dimedone, ethyl acetoacetate, 3‐methyl‐1‐phenyl‐1H‐pyrazol‐5(4H)‐ one, and α‐naphthol, respectively, with aromatic aldehydes and malononitrile in refluxing aqueous ethanol. The heterogeneous solid base showed similar efficiency when reused in consecutive reactions.
文摘An efficient heterogeneous Pd catalytic system has been developed, based on immobilization of Pd nanoparticles (PNPs) on a silica-bonded N-propylpiperazine (SBNPP) substrate. The SBNPP substrate effectively stabilizes the PNPs and improves their stability against aggregation. The catalytic activity of this catalyst was investigated in the cyanation of aryl halides with K4[Fe(CN)6 ] as the cyanide source. The catalyst could be recycled several times without appreciable loss of catalytic activity.
基金Persian Gulf University Research Council for partial support of this work, PGU/FS/6-2/1390/694
文摘A simple and efficient procedure for the preparation of silica-bonded N-propylpiperazine sodium n-propionate(SBPPSP) by the hydrolysis of silica-bonded N-propylpiperazine methyl n-propionate(SBPPMP) in hydrochloric acid(0.5 mol/L) followed by treatment with saturated sodium bicarbonate is described.The SBPPMP was obtained by the reaction of 3-silica-bonded N-propylpiperazine and methyl acrylate in methanol.SBPPSP was used as a recyclable basic catalyst for the synthesis of 3,4-dihydropyrano[c]chromenes by the reaction of aromatic aldehydes,malononitrile,and 4-hydroxycoumarin in aqueous ethanol(1:1 v/v) under reflux conditions.Biscoumarins were also obtained via condensation of aldehydes and 4-hydroxycoumarin in aqueous ethanol(1:1 v/v) under reflux conditions.The catalyst could be recycled several times without any additional treatment.
