Synthesis, structure, and reactivity of (η5:η1-C5Me4(CH2)2NMe2)Re(CO)2. Electron transfer behavior of a nitrosyl derivative

The UV irradiation of a hexane solution of the complex (eta(5)-C5Me4(CH2)(2)NMe2)Re(CO)(3) (1) afforded the chelated species (eta(5):eta(1)-C5Me4(CH2)(2)NMe2)Re(CO)(2) (2). The molecular structure of 2 has been determined by X-ray crystallography. The reaction of 2 with two-electron donor ligands yields (eta(5)-C5Me4(CH2)(2)NMe2)Re(CO)(2)(L) (1, L = CO; 3, L = PMe3). The chelated species 2 also reacts with MeOTf, HBF4, and I-2 to form the cationic compounds trans-[(eta(5)-C5Me4(CH2)(2)NMe2)Re(CO)(2)X](+) ([4](+), X = Me; [5](+), X = H; [6](+), X = 1). The trans stereochemistry of 4-6 have been assigned on the basis of nu(CO) IR intensities and C-13 NMR spectroscopy. Also, complex 2 reacts with nitrosyl tetrafluoroborate to yield [(eta(5)-C5Me4(CH2)(2)NMe2NO)Re(CO)(2)(NO)]BF4 ([7](2+)). The redox behavior of the {ReNO}(6) complex [7](2+) was studied and the products obtained after two-electron reduction were characterized by IR. DFT calculations were done to optimize the structure of [7](2+) and to study the effect of the sidearm coordination on the electronic structure of a cyclopentadienyl {ReNO}(8) complex. (C) 2014 Elsevier B.V. All rights reserved.