The First Structurally Confirmed Paddlewheel Compound with an M27+ Core: [Os2(hpp)4Cl2](PF6)

• DOI: 10.1021/ic026250t
• Publication Date: 2003-02-03T20:58:47Z
• Authors: F. Albert Cotton; Naresh S. Dalal; Penglin Huang; Carlos A. Murillo; Ashley C. Stowe; Xiaoping Wang
• Keywords: Unpaired electron

Oxidation of Os(2)(hpp)(4)Cl(2), 1 (hpp = the anion 1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine), with (FeCp(2))PF(6) produces air-stable [Os(2)(hpp)(4)Cl(2)]PF(6), 2. This is first structurally confirmed metal-metal bonded paddlewheel compound having an M(2)(7+) core. The Os-Os distances for two crystalline forms, 2.2acetone and 2.hexane, are 2.3309(4) 2.3290(6) A, respectively. EPR, (1)H NMR, magnetization data indicate that 2 has unpaired electron exceptionally low g value 0.791 +/- 0.037. An electrochemical study shows there a quasireversible wave corresponding to more highly oxidized species unprecedented Os(2)(8+)