An efficient and practical synthesis of specially 2-amino-4H-pyrans catalyzed by C4(DABCO-SO3H)2·4Cl

•Efficient synthesis of specially 2-amino-4H-pyrans.•Green conditions for the synthesis of the requested products.•Preparation of chromatic compounds in high yields and short reaction times.•Introduction of an efficient catalyst with lower loading.

A mild, simple and convenient procedure for the synthesis of spiro-oxindole heterocycles containing fused 4H-pyran ring and also bis-2-amino-4H-pyrans derivatives was described using C4(DABCO-SO3H)2·4Cl as a nano, efficient, cheap, and reusable catalyst under mild and homogeneous conditions.

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