Structural studies of phosphor-1,1-diselenoato Mn(I) and Re(I) complexes

Mononuclear complexes of the type, M(CO)4[Se2P(OR)2] (M = Mn, R = iPr, 1a; Et, 1b; M = Re, R = iPr, 3a; Et, 3b) can be prepared from either [-Se(Se)P(OiPr)2]2[-Se(Se)P(OiPr)2]2 (A) or [Se{-Se(Se)P(OEt)2}2] (B) with M(CO)5Br. O,O  ′-dialkyl diselenophosphate ([(RO)2PSe2]-[(RO)2PSe2]-, abbreviated as dsep) ligands generated from A and B act as a chelating ligand in these complexes. Upon refluxing in acetonitrile, these mononuclear complexes yield dinuclear complexes with a general formula of [M2(CO)6{Se2P(OR)2}2] (M = Mn, R = iPr, 2a; Et, 2b; M = Re, R = iPr, 4a; Et, 4b). Dsep ligands display a triconnective, bimetallic bonding mode in the dinuclear compounds and this kind of connective pattern has never been identified in any phosphor-1,1-diselenoato metal complexes. Compounds 2b, 3b, and 4 are structurally characterized. Compounds 2b and 3b display weak, secondary Se⋯Se interactions in their lattices.

Graphical abstractFacile syntheses and structural characterizations of Mn(I) and Re(I) complexes of dialkyl diselenophosphate are presented. Intermolecular Se…Se interactions revealed in the lattice form supramolecularly bound 1D network and dimeric species.Figure optionsDownload full-size imageDownload as PowerPoint slide