Amine-functionalized hyper-crosslinked polyphenanthrene as a metal-free catalyst for the synthesis of 2-amino-tetrahydro-4H-chromene and pyran derivatives

The hyper-crosslinked microporous polyphenanthrene spheres were fabricated simply by the polymerization of phenanthrene using bromomethyl methyl ether as a bridging agent in the absence of any templates. The organic spheres were subjected to amine-functionalizing on the periphery of them using unreacted bromomethyl groups. The amine-functionalized microporous polyphenthrene could be employed as a highly effective and stable solid basic catalyst for the syntheses of functionalized 2-amino-tetrahydro-4H-chromene and pyran derivatives. The significant features of these reactions are high product yields, environmental benignity, short reaction time, broad substrate scope, and non requirement of toxic solvents. Furthermore, the catalyst can be reused up to four times without significant loss of activity. (C) 2017 Elsevier B.V. All rights reserved.