title: Technetium and rhenium pentacarbonyl complexes with C₂ and C₁₁ ω-isocyanocarboxylic acid esters.
abstract: Technetium(I) and rhenium(I) pentacarbonyl complexes with ethyl 2-isocyanoacetate and methyl 11-isocyanoundecanoate, [M(CO)5(CNCH2COOEt)]ClO4 (M = Tc (1) and Re (2)) and [M(CO)5(CN(CH2)10COOMe)]ClO4 (M = Tc (3) and Re (4)), were prepared and characterized by IR, (1)H NMR, and (13)C{(1)H} NMR spectroscopy. The crystal structures of 1 and 2 were determined using single-crystal X-ray diffraction. The kinetics of thermal decarbonylation of technetium complexes 1 and 3 in ethylene glycol was studied by IR spectroscopy. The rate constants and activation parameters of this reaction were determined and compared with those for [Tc(CO)6](+). It was found that rhenium complexes 2 and 4 were stable with respect to thermal decarbonylation. Histidine challenge reaction of complexes 1 and 2 in phosphate buffer was examined by IR spectroscopy. In the presence of histidine, the rhenium pentacarbonyl isocyanide complex partially decomposes to form an unidentified yellow precipitate. Technetium analogue 1 is more stable under these conditions.
authors.affiliation: Khlopin Radium Institute , 2-i Murinskii pr. 28, St. Petersburg, 194021 Russia.
authors.forename: Alexander E
authors.initials: AE
authors.lastname: Miroslavov
authors.forename: Yuriy S
authors.initials: YS
authors.lastname: Polotskii
authors.forename: Vladislav V
authors.initials: VV
authors.lastname: Gurzhiy
authors.forename: Alexander Yu
authors.initials: AY
authors.lastname: Ivanov
authors.forename: Alexander A
authors.initials: AA
authors.lastname: Lumpov
authors.forename: Margarita Yu
authors.initials: MY
authors.lastname: Tyupina
authors.forename: Georgy V
authors.initials: GV
authors.lastname: Sidorenko
authors.forename: Peter M
authors.initials: PM
authors.lastname: Tolstoy
authors.forename: Daniil A
authors.initials: DA
authors.lastname: Maltsev
authors.forename: Dmitry N
authors.initials: DN
authors.lastname: Suglobov
mesh_terms: D002264:Carboxylic Acids / Q000737:chemistry; D004952:Esters / Q000737:chemistry; D009682:Magnetic Resonance Spectroscopy; D009942:Organometallic Compounds / Q000138:chemical synthesis*; D015609:Organotechnetium Compounds / Q000138:chemical synthesis*; D012211:Rhenium / Q000737:chemistry*; D013055:Spectrophotometry, Infrared; D013667:Technetium / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D002264:Carboxylic Acids; D004952:Esters; D009942:Organometallic Compounds; D015609:Organotechnetium Compounds; D012211:Rhenium; D013667:Technetium