Problem Solving and Environmentally Benign Approach toward Diversity Oriented Synthesis of Novel 2-Amino-3-phenyl (or Alkyl) Sulfonyl-4H-chromenes at Ambient Temperature

Abstract

A problem solving, environmentally benign, and diversity oriented protocol has been described for multicomponent synthesis of medicinally privileged 2-amino-3-phenyl (or methyl) sulfonyl-4H-chromenes by one-pot, three component condensation among aldehydes, phenyl (or methyl) sulphonyl acetonitrile, and α-naphthol, 3-dimethylamino phenol, 4-hydroxy-N-methyl-quinoline-2-one as well as 4-hydroxycarbazole, using diethylamine as an efficient organo catalyst. The catalyst employed is commercially available, inexpensive, and nontoxic. Ambient reaction conditions, very high yields, wide scope, and avoidance of conventional isolation as well as chromatographic purification have improved the practical utility of this protocol manifold.

Pyranoquinolone derivatives: A potent multi‐targeted pharmacological scaffold

“…Earlier, it was mentioned that pyrano‐[3,2‐c]‐quinolin‐5‐one products could have been produced by combining 4‐hydroxyquinolin‐2‐( 1H )‐ones with aldehydes and malononitrile in a three‐component reaction. This reaction can be accelerated with piperidine, ammonium acetate, TEBA or triethylamine [21, 60, 67, 82].…”

Diastereoselective Synthesis of Functionalized 5‐Amino‐3,4‐Dihydro‐2H‐Pyrrole‐2‐Carboxylic Acid Esters: One‐Pot Approach Using Commercially Available Compounds and Benign Solvents

“…The heterocyclic compounds 5 p , q were isolated in satisfactory overall yield and d.r., considering the susceptibility of furfural and hydroxymethylfurfural to decomposition. The protocol has some limitations when applied to aliphatic aldehydes, which are known to suffer of competitive pathways in the Knoevenagel condensation, affording the alkenes in very low yields [12b, 15] …”

Ethylenediamine Functionalized Cellulose Acetate [CAEDA] Nanosized Solid Base Catalyst in the Synthesis of 2‐Amino‐4H‐Chromenes and 5‐Substituted‐1H‐Tetrazoles

“…[27,28] Neodegradable diseases like Alzheimer's disease, insomnia etc have been treated by the application of these derivatives. [29,30] Anti-fungal activities have been shown by two derivatives of chromenes i.e 5,7-dimethoxy-2,8-dimethyl-2H-chromene (1) and 5,7-dimethoxy-2-methyl-2H-chromene (2) which have been extracted from calyptranthes tricona oil. Blood anti-coagulant warfarin activity have been shown by pyranopyranone (3).…”

“…2‐amino‐4 H ‐chromenes exhibits a great utility in the field of cosmetics, pigments and biodegradable agrochemicals [27,28] . Neodegradable diseases like Alzheimer's disease, insomnia etc have been treated by the application of these derivatives [29,30] . Anti‐fungal activities have been shown by two derivatives of chromenes i.e 5,7‐dimethoxy‐2,8‐dimethyl‐2 H ‐chromene (1) and 5,7‐dimethoxy‐2‐methyl‐2 H ‐chromene (2) which have been extracted from calyptranthes tricona oil.…”