Sulfuric acid-modified polyethylene glycol 6000（PEG-OSO_3H） was applied as an efficient and recyclable catalyst for the synthesis ofβ-amino carbonyl compounds via the Mannich reaction between aldehydes,aromatic ketones and aromatic amines at room temperature using PEG400-H_2O（1：1） as environment-friendly solvents.The reactions were completed in short times and mild reaction conditions with good to excellent yields.
A self-intermolecular cyclocondensation reaction of 3,4-dihydropyrimidine-2-thione（DHPM） to give a novel tricyclic structure containing DHPM core in the presence of diethyl azodicarboxylate（DEAD） and triphenylphosphine（TPP） at room temperature is reported.
