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1. Lewis base-complexed magnesium dithiolenes

   https://doi.org/10.1039/C9CC03427G  

   Wang, Yuzhong; Maxi, Nirva A.; Xie, Yaoming; Wei, Pingrong; Schaefer, Henry F.; Robinson, Gregory H. (July 2019, Chemical Communications)

   The first magnesium-based dithiolene, 2 , was prepared by reaction of the lithium dithiolene radical, 1˙ , with 2-mesitylmagnesium bromide. Reaction of 2 with N-heterocyclic carbenes (in toluene) gave a carbene-stabilized magnesium monodithiolene complex, 3 . Complex 3 , in turn, is readily converted to a THF-solvated magnesium bis-dithiolene dianion, 4 , via partial hydrolysis in polar solvents ( i.e. , THF/CH 3 CN). Compounds 2 , 3 and 4 have been spectroscopically and structurally characterized and probed by DFT computations. 

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2. Lewis Acid Supported Nickel Nitrenoids

   https://doi.org/10.1002/anie.202313156  

   Juda, Cristin E.; Casaday, Claire E.; Clarke, Ryan M.; Litak, Nicholas P.; Campbell, Brandon M.; Chang, Tieyan; Zheng, Shao‐Liang; Chen, Yu‐Sheng; Betley, Theodore A. (November 2023, Angewandte Chemie International Edition)

   Abstract Metalation of the polynucleating ligand^F,tbsLH₆(1,3,5‐C₆H₉(NC₆H₃−4‐F−2‐NSiMe₂^tBu)₃) with two equivalents of Zn(N(SiMe₃)₂)₂affords the dinuclear product (^F,tbsLH₂)Zn₂(1), which can be further deprotonated to yield (^F,tbsL)Zn₂Li₂(OEt₂)₄(2). Transmetalation of2with NiCl₂(py)₂yields the heterometallic, trinuclear cluster (^F,tbsL)Zn₂Ni(py) (3). Reduction of3with KC₈affords [KC₂₂₂][(^F,tbsL)Zn₂Ni] (4) which features a monovalent Ni centre. Addition of 1‐adamantyl azide to4generates the bridging μ³‐nitrenoid adduct [K(THF)₃][(^F,tbsL)Zn₂Ni(μ³‐NAd)] (5). EPR spectroscopy reveals that the anionic cluster possesses a doublet ground state (S=). Cyclic voltammetry of5reveals two fully reversible redox events. The dianionic nitrenoid [K₂(THF)₉][(^F,tbsL)Zn₂Ni(μ³‐NAd)] (6) was isolated and characterized while the neutral redox isomer was observed to undergo both intra‐ and intermolecular H‐atom abstraction processes. Ni K‐edge XAS studies suggest a divalent oxidation state for the Ni centres in both the monoanionic and dianionic [Zn₂Ni] nitrenoid complexes. However, DFT analysis suggests Ni‐borne oxidation for5. 

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3. Computing Lewis Weights to High Precision

   https://doi.org/10.1137/1.9781611977073.107  

   Fazel, Maryam; Lee, Yin Tat; Padmanabhan, Swati; Sidford, Aaron (January 2022, Proceedings of the 2022 Annual ACM-SIAM Symposium on Discrete Algorithms (SODA 2022))
4. Computing Lewis Weights to High Precision

   Fazel, Maryam; Lee, Yin Tat; Padmanabhan, Swati; Sidford, Aaron (January 2022, ACM-SIAM Symposium on Discrete Algorithms)
5. L1 Regression with Lewis Weights Subsampling

   Parulekar, Aditya; Parulekar, Advait; Price, Eric (August 2021, RANDOM)

   We consider the problem of finding an approximate solution to ℓ1 regression while only observing a small number of labels. Given an n×d unlabeled data matrix X, we must choose a small set of m≪n rows to observe the labels of, then output an estimate βˆ whose error on the original problem is within a 1+ε factor of optimal. We show that sampling from X according to its Lewis weights and outputting the empirical minimizer succeeds with probability 1−δ for m>O(1ε2dlogdεδ). This is analogous to the performance of sampling according to leverage scores for ℓ2 regression, but with exponentially better dependence on δ. We also give a corresponding lower bound of Ω(dε2+(d+1ε2)log1δ). 

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