Luminescent 1-1,3-benzazaphospholes.

2-R-1-1,3-Benzazaphospholes (R-BAPs) are an interesting class of σP heterocycles containing P[double bond, length as m-dash]C bonds. While closely related 2-R-1,3-benzoxaphospholes (R-BOPs) have been shown to be highly photoluminescent materials depending on specific R substituents, photoluminescence of R-BAPs has been previously limited to an example having a fused carbazole ring system. Here we detail the synthesis and structural characterization of a new R-BAP (3c, R = 2,2'-dithiophene), and compare its photoluminescence against two previously reported R-BAPs (3a, R, R' = Me and 3b, R = 2-thiophene).

Preferential N-H⋯:C[double bond splayed right] hydrogen bonding involving ditopic -containing systems and -heterocyclic carbenes.

Hydrogen bonding plays a critical role in maintaining order and structure in complex biological and synthetic systems. -heterocyclic carbenes (NHCs) represent one of the most versatile tools in the synthetic chemistry toolbox, yet their potential as neutral carbon hydrogen bond acceptors remains underexplored. This report investigates this capability in a strategic manner, wherein carbene-based hydrogen bonding can be assessed by use of ditopic -containing molecules.