Sulfonic acid supported on hydroxyapatite-encapsulated-γ-Fe2O3 nanocrystallites as a magnetically separable catalyst for one-pot reductive amination of carbonyl compounds

Abstract

A novel, environmentally friendly procedure has been developed for the preparation of secondary or tertiary amines by one-pot reductive amination of carbonyl compounds using sodium borohydride in the presence of a magnetically recoverable sulfonic acid supported on hydroxyapatite-encapsulated-γ-Fe2O3 [γ-Fe2O3@HAP-SO3H] at room temperature. The catalyst was easily separated from the reaction mixture by applying an external magnet and reused for six cycles without significant loss of catalytic activity.