71763-30-9Relevant academic research and scientific papers
Metal complexes of sulfur-containing ligands. Synthesis and properties of a series of rhenium-substituted sulfonium salts [(η5-C5H5)Re(NO)(PPh3)(CH 2-)]nS+(CH3)3-n (n = 1-3)
McCormick, Fred B.,Gleason, William B.,Zhao, Xiande,Heah, Poh Choo,Gladysz
, p. 1778 - 1785 (2008/10/08)
Reaction of [(η5-C5H5)Re(NO)(PPh3)(=CH 2)]+PF6- (1, -78°C) with CH3SCH3 gives sulfonium salt [(η5-C5H5)Re(NO)(PPh3)(CH 2S(CH3)2)]+PF6 - (2, 90-95%). Variable-temperature NMR data show that CH3SCH3 reversibly gives from 2 with ΔG?262 = 14.2 kcal/mol and ΔG?289 = 12.9 kcal/mol. Reaction of 2 with PPh3 and pyridine give [(η5-C5H5)Re(NO)(PPh3)(CH 2PPh3)]+PF6- (4, 76%) and [(η5-C5H5)Re(NO)(PPh3)(CH 2N(CH)4CH)]+PF6- (5), respectively. Reaction of 2 with RS- gives (η5-C5H5)Re(NO)(PPh3)(CH 2SR) (6, 79-95%; R = CH3 (a), C6H5 (b), CH2C6H5 (c)). Reaction of 1 or 2 with 6a gives binuclear sulfonium salt [(η5-C5H5)Re(NO)(PPh3)(CH 2-)]2S+CH3PF6- (7+PF6-, 89-92%) as a 2:1:1 mixture of diastereomers. Treatment of 7+PF6- with NaI/CH3CN gives 7+I-, which crystallizes as one diastereomer as shown by X-ray crystallography. Crystal data: orthorhombic, Pnma; a = 18.348 (6) A?, b = 20.767 (2) A?, c = 13.944 (2) A?; Z = 4. Reaction of 7+PF6- with PPh3 gives 4 (90%) and 6a (71%). Pyrolysis of 7+PF6- (80°C, 8 h) gives (η5-C5H5)Re(NO)(PPh3)(CH 3) (8, 84%) and [(η5-C5H5)Re(NO)(PPh 3)(=CHSCH3)]+PF6- (9, 82%). Reaction of 1 with Na2S gives trinuclear sulfonium salt [(η5-C5H5)Re(NO)(PPh3)(CH 2-)]3S+PF6- (10, 84%). Complex 10 reacts only sluggishly with PPh3 (65°C). These reactions show that the (η5-C5H5)Re(NO)(PPh3) moiety significantly enhances the basicity of sulfide sulfur atoms that are β to it.
