The reaction of the water-soluble monophosphine tris(hydroxymethyl)phosphine (THP, 1) with [ReO2(py)(4)]Cl produced either trans,trans,trans-[ReO2(THP)(2)(py)(2)]Cl (3, referred to as trans-[ReO2(THP)(2)(py)(2)]Cl throughout the text) or trans,cis,cis-[ReO2(THP)(2)(py)(2)]Cl (4, referred to as cis-[ReO2(THP)(2)(py)(2)]Cl throughout the text) depending on the reaction conditions. In contrast, the reaction of THP with ReO2I(PPh3)(2) in biphasic media produced the novel, neutral, cyclic tetranuclear, rhenium(V) alkoxide 5 in low yields. A similar reaction of bis(hydroxymethyl)phenylphosphine (2) with [ReO2(py)(4)]Cl produced the trans,trans,trans-[ReO2(PPh(CH2OH)(2))(2)-(py)(2)]Cl complex (6, referred to as trans-[ReO2{PPh(CH2OH)(2)}(2)(py)(2)]Cl throughout the text) in high yields. All compounds were characterized by P-31, H-1, and C-13 NMR spectroscopy and mass spectroscopy. X-ray data for 3:monoclinic, C2/c, a = 17.7964(11) Angstrom, b = 8.8972(6) Angstrom, c = 15.3247(9) Angstrom, beta = 97.683(1)degrees, Z= 4, R = 0.0179 (R-w = 0.0426). X-ray data for 4 : monoclinic, P2(1)/n, a = 12.1025(7) Angstrom, b = 9.8274(5) Angstrom, c = 22.4272(12) Angstrom, beta = 96.807(1)degrees, Z = 2, R = 0.0437 (R-w = 0.0887). X-ray data for 6 : monoclinic, P2(1)/n, a = 9.3654(5) Angstrom, b = 13.2578(7) Angstrom, c = 12.0257(7) Angstrom, b = 107.0480(10)degrees, Z = 2, R = 0.0218 (R-w = 0.0578).