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1. Organo‐Functionalized Lacunary Double Cubane‐Type Oxometallates: Synthesis, Structure, and Properties of [(M II Cl) 2 (V IV O) 2 {((HOCH 2 CH 2 )(H)N(CH 2 CH 2 O))(HN(CH 2 CH 2 O) 2 )} 2 ] (M=Co, Zn)

   https://doi.org/10.1002/chem.202301389  

   Shuaib, Damola T. ; Swenson, LaSalle ; Kaduk, James A. ; Chang, Tieyan ; Chen, Yu‐Sheng ; McNeely, James ; Khan, M. Ishaque ( October 2023 , Chemistry – A European Journal)

   Organofunctionalized tetranuclear clusters [(M^IICl)₂(V^IVO)₂{((HOCH₂CH₂)(H)N(CH₂CH₂O))(HN(CH₂CH₂O)₂)}₂] (1, M=Co,2: M=Zn) containing an unprecedented oxometallacyclic {M₂V₂Cl₂N₄O₈} (M=Co, Zn) framework have been prepared by solvothermal reactions. The new oxo‐alkoxide compounds were fully characterized by spectroscopic methods, magnetic susceptibility measurement, DFT and ab initio computational methods, and complete single‐crystal X‐ray diffraction structure analysis. The isostructural clusters are formed of edge‐sharing octahedral {VO₅N} and trigonal bipyramidal {MO₃NCl} units. Diethanolamine ligates the bimetallic lacunary double cubane core of1and2in an unusual two‐mode fashion, unobserved previously. In the crystalline state, the clusters of1and2are joined by hydrogen bonds to form a three‐dimensional network structure. Magnetic susceptibility data indicate weakly antiferromagnetic interactions between the vanadium centers [J_iso(V^IV−V^IV)=−5.4(1); −3.9(2) cm⁻¹], and inequivalent antiferromagnetic interactions between the cobalt and vanadium centers [J_iso(V^IV−Co^II)=−12.6 and −7.5 cm⁻¹] contained in1.

    

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2. Characterization of the Titanium(III) Tris(alkyl) Ti{CH(SiMe 3 ) 2 } 3 and its Conversion to a Dimeric Alkyl‐Bridged Titanium(IV) Species

   https://doi.org/10.1002/chem.202404696  

   McLoughlin, Connor_P ; Witt, Anthony_J ; Maijala, Anni ; Shiau, Angela_A ; Rao, Guodong ; David_Britt, R. ; Tuononen, Heikki_M ; Power, Philip_P ( January 2025 , Chemistry – A European Journal)

   The reaction of three equivalents of LiCH(SiMe₃)₂with TiCl₃(NMe₃)₂afforded the rare homoleptic Ti(III) alkyl Ti{CH(SiMe₃)₂}₃(1) which crystallized as blue needles in 32 % yield. Single crystal X‐Ray data for1showed a trigonal pyramidal coordination geometry around titanium, which could be ascribed to weak interactions between the C−H bonds and the Ti(III) atom based on computational results. X‐band EPR spectroscopy gives spectral parameters consistent with the proposed Ti(III) formulation. Solutions of1are unstable at room temperature owing to intramolecular C−H activation that gave a dimeric Ti(IV) complex [{(Me₃Si)₂HC}Ti{μ‐CHSiMe₂CHSiMe₃}]₂(2).

    

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3. Further Studies of Co III (TIM) Mono‐Alkynyl and Bis‐Alkynyl Complexes

   https://doi.org/10.1002/ejic.202200641  

   Rodriguez Segura, Leobardo ; Cox, Kenneth E. ; Samayoa‐Oviedo, Hugo Y. ; Ren, Tong ( December 2022 , European Journal of Inorganic Chemistry)

   A new series of mono‐ and bis‐alkynyl Co^III(TIM) complexes (TIM=2,3,9,10‐tetramethyl‐1,4,8,11‐tetraazacyclotetradeca‐1,3,8,10‐tetraene) is reported herein. Thetrans‐[Co(TIM)(C₂R)Cl]⁺complexes were prepared from the reaction betweentrans‐[Co(TIM)Cl₂]PF₆and HC₂R (R=tri(isopropyl)silyl or TIPS (1), ‐C₆H₄‐4‐^tBu (2), ‐C₆H₄‐4‐NO₂(3 a), andN‐mesityl‐1,8‐naphthalimide or NAP^Mes(4 a)) in the presence of Et₃N. The intermediate complexes of the typetrans‐[Co(TIM)(C₂R)(NCMe)](PF₆)(OTf),3 band4 b, were obtained by treating3 aand4 a, respectively, with AgOTf in CH₃CN. Furthermore, bis‐alkynyltrans‐[Co(TIM)(C₂R)₂]PF₆complexes,3 cand4 c, were generated following a second dehydrohalogenation reaction between3 band4 b, respectively, and the appropriate HC₂R in the presence of Et₃N. These new complexes have been characterized using X‐ray diffraction (2,3 a,4 a, and4 c), IR,¹H NMR, UV/Vis spectroscopy, fluorescent spectroscopy (4 c), and cyclic voltammetry.

    

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4. The β‐Agostic Structure in (C 5 Me 5 ) 2 Sc(CH 2 CH 3 ): Solid‐State NMR Studies of (C 5 Me 5 ) 2 Sc−R (R=Me, Ph, Et)

   https://doi.org/10.1002/ange.201805738  

   Culver, Damien B. ; Huynh, Winn ; Tafazolian, Hosein ; Ong, Ta‐Chung ; Conley, Matthew P. ( July 2018 , Angewandte Chemie)

   Multinuclear solid‐state NMR studies of Cp*₂Sc−R (Cp*=pentamethylcyclopentadienyl; R=Me, Ph, Et) and DFT calculations show that the Sc−Et complex contains a β‐CH agostic interaction. The static central transition⁴⁵Sc NMR spectra show that the quadrupolar coupling constants (C_q) follow the trend of Ph≈Me>Et, indicating that the Sc−R bond is different in Cp*₂Sc−Et compared to the methyl and phenyl complexes. Analysis of the chemical shift tensor (CST) shows that the deshielding experienced by Cβ in Sc−CH₂CH₃is related to coupling between the filled σ_C‐Corbital and the vacantorbital.

    

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5. The β‐Agostic Structure in (C 5 Me 5 ) 2 Sc(CH 2 CH 3 ): Solid‐State NMR Studies of (C 5 Me 5 ) 2 Sc−R (R=Me, Ph, Et)

   https://doi.org/10.1002/anie.201805738  

   Culver, Damien B. ; Huynh, Winn ; Tafazolian, Hosein ; Ong, Ta‐Chung ; Conley, Matthew P. ( July 2018 , Angewandte Chemie International Edition)

   Multinuclear solid‐state NMR studies of Cp*₂Sc−R (Cp*=pentamethylcyclopentadienyl; R=Me, Ph, Et) and DFT calculations show that the Sc−Et complex contains a β‐CH agostic interaction. The static central transition⁴⁵Sc NMR spectra show that the quadrupolar coupling constants (C_q) follow the trend of Ph≈Me>Et, indicating that the Sc−R bond is different in Cp*₂Sc−Et compared to the methyl and phenyl complexes. Analysis of the chemical shift tensor (CST) shows that the deshielding experienced by Cβ in Sc−CH₂CH₃is related to coupling between the filled σ_C‐Corbital and the vacantorbital.

    

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