- 作者: 施振祥 ; 王曉蓴 ; 楊小筠 等
- 中文摘要: The 3-methylsydnone (CH/sub 3/Sd) and 3-phenylsydnone(PhSd) complexes of pentacyanoferrate(II) were prepared in aqueous solution by the reaction of Fe(CN)/sub 5/OH/sub 2//sup 3-/ with excess ligand. Metal to ligand charge transfer transitions were observed for both complexes at 442nm(CH/sub 3/Sd) and 494nm (PhSd), respectively. The reduction potentials were measured with the E/sub f/ values of 0.65 and 0.67V (vs. NHE) for CH/sub 3/Sd and PhSd, respectively, at 25.degree.C, .mu.=0.10M LiClO/sub 4/ and pH=5. The kinetics of the substitution reaction were also investigated, and k/sub f/ and k/sub d/ values (25.degree.C,.mu.=0.10M LiClO/sub 4/, pH=5) are (5.4.plmin.0.2)* 10/sup -2/M/sup -1/s/sup -1/ and (1.4.plmin.0.1)*10/sup -5/ s/sup -1/ ( CH/sub 3/Sd), (8.8.plmin.0.1)*10/sup -2/M/sup -1/ s/sup -1/ and (4.7.plmin.0.1)*10/sup -5/s/sup -1/ (PhSd). The k/sub f/ values for both sydnone complexes are approximately four orders of magnitude smaller than other pentacyanoferrate(II) complexes with neutral ligands. The difference may arise from the mesoionic character of the sydnone compounds rather than via a different reaction mechanism. Spectroscopic, kinetic and electrochemical results all suggest that the sydnone ring shows a better. pi.-backbonding stabilization with Fe(CN)/sub 5//sup 3-/ moiety than that of the pyridine ring.
- 英文摘要: --
- 中文關鍵字: Sydnone; Pentacyanoferrate; 3-Methylsydnone; 3-Phenylsydnone; Kinetics
- 英文關鍵字: 雪梨酮;戊氰高鐵酸鹽;3-甲基雪梨酮;3-苯基雪梨酮;動力學