%0 Journal Article %1 Mondal.2014b %A Mondal, Kartik Chandra %A Samuel, Prinson P. %A Roesky, Herbert W. %A Carl, Elena %A Herbst-Irmer, Regine %A Stalke, Dietmar %A Schwederski, Brigitte %A Kaim, Wolfgang %A Ungur, Liviu %A Chibotaru, Liviu F. %A Hermann, Markus %A Frenking, Gernot. %D 2014 %J Journal of the American Chemical Society %K MO alkyl amino bond cAAC carbene cation cobalt crystal cyclic dinuclear electrochem mol prepn prepn;stabilization radical redox;mol redox;optimized structure %N 5 %P 1770--1773 %R 10.1021/ja4123285 %T Stabilization of a Cobalt-Cobalt Bond by Two Cyclic Alkyl Amino Carbenes %V 136 %X (Me2-cAAC:)2Co2 (2, where Me2-cAAC: = cyclic alkyl amino carbene, :C(CH2)(CMe2)2N-2,6-iPr2C6H3) was synthesized via the redn. of precursor (Me2-cAAC:CoII(m-Cl)Cl)2 (1) with KC8. 2 Contains two Co atoms in the formal oxidn. state zero. Magnetic measurement revealed that 2 has a singlet spin ground state S = 0. The cyclic voltammogram of 2 exhibits both 1-electron oxidn. and redn., indicating the possible synthesis of stable species contg. 2.bul.- and 2.bul.+ ions. The latter was synthesized via redn. of 1 with required equiv. of KC8 and characterized as [(Me2-cAAC:)2Co2].bul.+OTf- (2.bul.+OTf-). ESR spectroscopy of 2.bul.+ reveals the coupling of the electron spin with 2 equiv 59Co isotopes, leading to a (Co0.5)2 state. The exptl. Co1-Co2 bond distances are 2.6550(6) and 2.4610(6) \AA for 2 and 2.bul.+OTf-, resp. Theor. study revealed that both 2 and 2.bul.+OTf- possess a Co-Co bond with an av. value of 2.585 \AA. A slight increase of the Co-Co bond length in 2 is more likely to be caused by the strong p-accepting property of cAAC. 2.bul.+ Is only 0.8 kcal/mol higher in energy than the energy min. The shortening of the Co-Co bond of 2.bul.+ is caused by intermol. interactions. [on SciFinder(R)]

@article{Mondal.2014b, abstract = {(Me2-cAAC:)2Co2 (2, where Me2-cAAC: = cyclic alkyl amino carbene, :C(CH2)(CMe2)2N-2,6-iPr2C6H3) was synthesized via the redn. of precursor (Me2-cAAC:CoII(\textgreek{m}-Cl)Cl)2 (1) with KC8. 2 Contains two Co atoms in the formal oxidn. state zero. Magnetic measurement revealed that 2 has a singlet spin ground state S = 0. The cyclic voltammogram of 2 exhibits both 1-electron oxidn. and redn., indicating the possible synthesis of stable species contg. 2.bul.- and 2.bul.+ ions. The latter was synthesized via redn. of 1 with required equiv. of KC8 and characterized as [(Me2-cAAC:)2Co2].bul.+OTf- (2.bul.+OTf-). ESR spectroscopy of 2.bul.+ reveals the coupling of the electron spin with 2 equiv 59Co isotopes, leading to a (Co0.5)2 state. The exptl. Co1-Co2 bond distances are 2.6550(6) and 2.4610(6) {\AA} for 2 and 2.bul.+OTf-, resp. Theor. study revealed that both 2 and 2.bul.+OTf- possess a Co-Co bond with an av. value of 2.585 {\AA}. A slight increase of the Co-Co bond length in 2 is more likely to be caused by the strong \textgreek{p}-accepting property of cAAC. 2.bul.+ Is only 0.8 kcal/mol higher in energy than the energy min. The shortening of the Co-Co bond of 2.bul.+ is caused by intermol. interactions. [on SciFinder(R)]}, added-at = {2019-07-15T13:41:23.000+0200}, author = {Mondal, Kartik Chandra and Samuel, Prinson P. and Roesky, Herbert W. and Carl, Elena and Herbst-Irmer, Regine and Stalke, Dietmar and Schwederski, Brigitte and Kaim, Wolfgang and Ungur, Liviu and Chibotaru, Liviu F. and Hermann, Markus and Frenking, Gernot.}, biburl = {https://puma.ub.uni-stuttgart.de/bibtex/2d7791e6f29cf0edc60f48dc0e294618d/b_schwederski}, doi = {10.1021/ja4123285}, interhash = {4a2311f37e29acd451d46c61f8643b25}, intrahash = {d7791e6f29cf0edc60f48dc0e294618d}, issn = {0002-7863}, journal = {Journal of the American Chemical Society}, keywords = {MO alkyl amino bond cAAC carbene cation cobalt crystal cyclic dinuclear electrochem mol prepn prepn;stabilization radical redox;mol redox;optimized structure}, number = 5, pages = {1770--1773}, timestamp = {2019-07-15T11:42:10.000+0200}, title = {Stabilization of a Cobalt-Cobalt Bond by Two Cyclic Alkyl Amino Carbenes}, volume = 136, year = 2014 }