N-Phosphonyl/phosphinyl imines and group-assisted purification (GAP) chemistry/technology.

The development of environmentally benign, operationally simple, and economically viable synthetic methodologies has been a great challenge in organic synthesis. Group-assisted purification (GAP) chemistry was established to enable the synthesis of organic compounds without using traditional purification technologies, such as column chromatography and recrystallization. This concept/technology should encourage the synthetic community to make more efforts on searching for environmentally benign reagents and reactions to reduce the waste generated from silica and solvents, particularly toxic solvents; also, to reduce production/synthesis expenses, manpower, and energy. This review will discuss the GAP concept/technology and related reactions that were mainly conducted in the PI's laboratories after 2010.