Alginic acid: A mild and renewable bifunctional heterogeneous biopolymeric organocatalyst for efficient and facile synthesis of polyhydroquinolines.
Alginic acid, a widely used naturally occurring carbohydrate which is generally derived from brown seaweeds, can be considered as a bifunctional heterogeneous and green biopolymeric organocatalyst. Alginic acid, without any post-modification with active Bronsted or Lewis acid centers, was found to be a highly active, cost-effective, commercially-available, renewable and recoverable heterogeneous biopolymeric organocatalyst for the expeditious synthesis of polyhydroquinolines (PHQs). Polyhydroquinolines were synthesized from the four-component Hantzsch reaction of ethyl acetoacetate, different aldehydes, ammonium acetate and cyclic 1,3-diones under mild conditions in high to quantitative yields, 75-97%, using alginic acid. Furthermore, alginic acid was found to be reusable for at least 6 consecutive cycles without considerable loss of its catalytic activity.
['Dekamin|Mohammad G|MG|', 'Karimi|Zahra|Z|', 'Latifidoost|Zahra|Z|', 'Ilkhanizadeh|Siamand|S|', 'Daemi|Hamed|H|', 'Naimi-Jamal|M Reza|MR|', 'Barikani|Mehdi|M|']
D000464:Alginates D002384:Catalysis D060326:Chemistry Techniques, Synthetic D020723:Glucuronic Acid D006603:Hexuronic Acids D011108:Polymers D011804:Quinolines
Alginic acid Polyhydroquinolines (PHQs) Biopolymer Green chemistry Hantzsch esters Heterocycles Organocatalysis