Phosphorus Can Also Be a “Photocopy”

摘要

Organophosphorus compounds featuring p-p π bonds betweennphosphorus and carbon display close similarities to relatednmaterials having corresponding carbon-carbon π bonds, andnthus, phosphorus has come to be called a “carbon copy”.1a Whilenmany properties are mirrored between the two sets of compounds,nthere remain some that are not reflected when CdC unitsnare replaced by PdC (or PdP) units. The widespread attentionnon π-conjugated polymers for applications in areas such asnmolecular electronics, sensors, organic light-emitting diodesn(OLEDs), and solar photovoltaics led to a recent Nobel prizenawarded to the three pioneers of these materials.2 It would thusnseem natural to expect that related π-conjugated materialsnincorporating other sp2-hybridized elements as participatory unitsncould be realized. We and others have been seeking to exploitnand extend the analogies between carbon and phosphorus toncreate extended conjugated materials,3 such as phospha-PPVsn(Chart 1).