Polyethylene Glycol as a Green Medium for the Microwave-Assisted Synthesis of Guanamines

Abstract

The hazardous, toxic, and flammable solvents, methyl and ethyl cellosolves (2-methoxy- and 2-ethoxyethanols), are typically used as media for the synthesis of guanamines (1,3,5-triazine-2,4-diamines). We found that these problematic solvents can be efficiently replaced by a green alternative, polyethylene glycol 400 (PEG 400). The reaction efficiency in PEG 400 media was further improved by applying focused microwave irradiation. The method scope is illustrated by the preparation of twenty diverse 1,3,5-triazine-2,4-diamines.