Reaction of cyrhetrenylphosphines, of general formula (eta(5)-C5H4PR2)Re(CO)(2)L (R = Ph, L = CO (1); R = Cy; L = CO (2); R = Ph, L = PMe3 (3) and R = Ph, L = P(OMe)(3) (4)), with H2O2, BH3 center dot THF or selenium gives the respective cyrhetrenylphosphine oxides, boranes and selenides. These species were characterized by standard spectroscopic techniques (FT-IR, H-1 and (PNMR)-P-31). Based on the P-31-Se-77 coupling constant ((1)J(P-Se)) of the phosphine-selenides, we established the following order of basicity of the parent cyrhetrenylphosphine 2 > 3 > 4 > 1. We also confirmed the opposite electronic effects of the cyrhetrenyl and ferrocenyl groups attached to a PR2 unit. Finally, phosphine selenides 2c and 4c were structurally characterized by X-ray diffraction. (C) 2017 Elsevier B.V. All rights reserved.