This work describes the synthesis of a range of bioactive chromenes using a solid Brønsted organic base called ‘Tris Morpholino Methyl Mesitylene (TMMM)’. The TMMM was obtained in high yields by treating tris bromomethyl mesitylene (TBMM) with morpholine in the presence of K2CO3 in acetonitrile at RT. It was characterized by using 1H NMR, and 13C NMR spectroscopy. We developed a Brønsted base hydrotrope combined catalytic system (BBHC) by combining TMMM and hydrotrope (Sodium p-toluene sulphonate: NaPTS) for the cascade-type Knoevenagel-Michael addition reactions of various aldehydes and malononitrile with Kojic acid, 4-hydroxy coumarin, dimedone, and Lawsone in water. The methodology offers diversity-oriented synthesis (DOS) of dihydropyrano chromenes with high yields. The BBHC catalytic system showed at least four times recyclability without appreciable loss of its activity. TMMM is an odorless, solid organic base that can handle easily, it is also resistant to air and moisture. As TMMM is a solid base it can reduce evaporation losses improving safety and allowing its easy recovery and reuse. TMMM acts as a powerful Brønsted base that activates reactants, while an aqueous solution of NaPTS acts as a hydrotrope that increases the solubility of organic compounds in water.

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