Abstract

Analysis of the Cambridge Structural Database confirms the assertion that tri(N-pyrrolyl)phosphine, P(NC₄H₄)₃, is isosteric with triphenylphosphine and reveals that N-pyrrolyl rings have a greater propensity to exist in the solid state in certain conformations. Tri(N-pyrrolyl)phosphine ligands are able to interact with each other in a similar manner to PPh₃ giving rise to six-fold and four-fold pyrrolyl embraces. However, as a consequence of the five-membered pyrrolyl rings, vertex-to-face interactions are more common for P(NC₄H₄)₃ than for PPh₃.