55881-15-7Relevant articles and documents
The chemistry of cobalt acetate - IV.? the isolation and crystal structure of the symmetric cubane, tetrakis[(μ-acetato)(μ3-oxo) (pyridine)cobalt(III)] chloroform solvate, [Co4(μ-O)4(μ-CH3CO2) 4(C5H5N)4] 5CHCl3 and of the dicationic partial cubane, trimeric
Beattie, James K.,Hambley, Trevor W.,Klepetko, John A.,Masters, Anthony F.,Turner, Peter
, p. 1343 - 1354 (1998)
The isolation from cobalt(III) acetate and characterisation by single crystal X-ray diffraction (refined to R = 0.087, Rw = 0 084) of the symmetric neutral cubane, [Co4-(μ3-O)4(μ-CH3CO 2)4(C5H5N)4], and of the hexafluorophosphate salt (refined to R = 0.078, Rw = 0.073) of the trimeric dication, the partial cubane, [Co3(μ3-O)(μ-OH)3(μ-CH 3CO2)(CH3CO2)(C5H 5N)6]2+, are reported. The cubane crystallises as its chloroform solvate, [Co4(μ3-O)4(μ-CH3CO 2)4(C5H5N)4] · 5CHCl3, whilst the partial cubane crystallises as its water solvate, [Co3(μ,-O)(μ-OH)3(μ-CH3CO 2)(CH3CO2)(C5H5N) 6][PF6]2·2H2O. The cubane and partial cubane dication have average Co ... Co distances of 2.818(8), 2.683(6) and 2.918(6), 2.767(5) A, respectively, and average Co - μ3-O distances of 1.86 and 1.91 A, respectively.
Synthesis and characterization of some trinuclear cobalt(II) thiocarboxylates
Baranwal,Gupta, Tarkeshwar
, p. 1855 - 1864 (2002)
Some cobalt(II) complexes of thiocarboxylic acids with the general composition Co(SOCR′)2 and Co(SOCR′)(OOCR) [where R = C13H27, C15H31 or C17H35 and R′ = CH3 or C6H5] have been synthesized by substitution reactions and characterized by elemental analyses, spectral studies and magnetic moment measurements. The electrical conductance data indicate that (Co(SOCCH3)2 is a 1:2 electrolyte while the other complexes are non-electrolytes. IR spectra show the presence of bidentate and bridging modes of coordination for carboxylate and thiocarboxylate anions, respectively. Electronic spectral data and magnetic moment values indicate an octahedral environment around cobalt(II). The plausible structure for the trimeric species has been proposed on the basis of the physico-chemical studies. Thermoanalytical data indicate the complexes are stable upto 175°C, above which decomposition starts.
The Role of Iodanyl Radicals as Critical Chain Carriers in Aerobic Hypervalent Iodine Chemistry
Hyun, Sung-Min,Yuan, Mingbin,Maity, Asim,Gutierrez, Osvaldo,Powers, David C.
supporting information, p. 2388 - 2404 (2019/09/12)
Selective O2 utilization remains a substantial challenge in synthetic chemistry. Biological small-molecule oxidation reactions often utilize aerobically generated high-valent catalyst intermediates to effect substrate oxidation. Available synthetic methods for aerobic oxidation catalysis are largely limited to substrate functionalization chemistry by low-valent catalyst intermediates (i.e., aerobically generated Pd(II) intermediates). Motivated by the need for new chemical platforms for aerobic oxidation catalysis, we recently developed aerobic hypervalent iodine chemistry. Here, we report that in contrast to the canonical two-electron oxidation mechanisms for the oxidation of organoiodides, the developed aerobic hypervalent iodine chemistry proceeds via a radical chain mechanism initiated by the addition of aerobically generated acetoxy radicals to aryl iodides. Despite the radical chain mechanism, aerobic hypervalent iodine chemistry displays substrate tolerance similar to that observed with traditional terminal oxidants, such as peracids. We anticipate that these insights will enable new sustainable oxidation chemistry via hypervalent iodine intermediates. O2 is routinely utilized in biological catalysis to generate high-valent catalyst intermediates that engage in substrate oxidation chemistry. Analogous synthetic chemistry via aerobically generated high-valent intermediates would enable new sustainable synthetic methods but is largely unknown because of the challenges in selective O2 utilization. We have developed aerobic hypervalent iodine chemistry as a platform for coupling O2 reduction with a diverse set of substrate functionalization mechanisms. Many of the synthetic applications of hypervalent iodine reagents rely on selective two-electron oxidation-reduction chemistry. Here, we report that one-electron oxidation reactions pathways via iodanyl radical intermediates are critical in aerobic hypervalent iodine chemistry. The new appreciation for the critical role that iodanyl radicals can play in the synthesis of hypervalent iodine compounds will provide new opportunities in sustainable oxidation catalysis. Aerobic hypervalent iodine chemistry provides a strategy for coupling the one-electron chemistry of O2 with two-electron processes typical of organic synthesis. We show that in contrast to the canonical two-electron oxidation of aryl iodides, aerobic synthesis proceeds by a radical chain process initiated by the addition of aerobically generated acetoxy radicals to aryliodides to generate iodanyl radicals. Robustness analysis reveals that the developed aerobic oxidation chemistry displays substrate tolerance similar to that observed in peracid-based methods and thus holds promise as a sustainable synthetic method.
Kinetic stability of complexes of some d-metals with 3,3'- bis(dipyrrolylmethene) in the binary proton-donor solvent acetic acid-benzene
Antina,Guseva,V'yugin,Antina
, p. 1293 - 1297 (2013/01/14)
The kinetics of dissociation of Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Hg(II) binuclear homoleptic double-stranded helicates with bis(2,4,7,8,9- pentametyldipyrrolylmethen-3-yl)methane (H2L) of the [M 2L2] composition
