130523-30-7Relevant articles and documents
Flexible sandwich (8-Alkylnaphthyl α-Diimine) Catalysts in Insertion Polymerization
Ge, You,Li, Shuaikang,Fan, Weigang,Dai, Shengyu
supporting information, p. 5673 - 5681 (2021/05/04)
8-Arylnaphthyl substituents are privileged motifs frequently integrated into late-transition-metal catalysts, endowing them with an ability to retard chain transfer in ethylene polymerization. In this contribution, we disclose a sort of novel α-diiminenickel and -palladium complexes containing flexible 8-alkylnaphthyl in lieu of rigid 8-arylnaphthyl and their catalytic performance in ethylene polymerization. An interesting feature of these 8-alkylnaphthyl-substituted α-(diimine)PdMeCl complexes is that they present as a mixture of syn and anti isomers (syn:anti = ca. 1:1 ratio, determined by 1H and 13C NMR spectroscopy). In ethylene polymerization, these nickel complexes displayed high activity (up to 3.37 × 106 g mol-1 h-1) and generated branched polyethylenes with broad or bimodal molecular weight distributions (4.6-29.3), while the corresponding palladium complexes exhibited moderate activity, producing highly branched polyethylenes with unimodal and narrow molecular weight distributions (1.8). In ethylene (E)/methyl acrylate (MA) copolymerization, highly branched E-MA copolymers with considerable MA incorporations were achieved by these palladium complexes. Most interestingly, compared to rigid 8-arylnaphthyl-substituted α-diiminenickel and -palladium complexes, the flexible 8-alkylnaphthyl ones showed significantly improved activity and generated lower or comparable molecular weight polyethylenes or E-MA copolymers.
INHIBITORS OF KRAS G12C PROTEIN AND USES THEREOF
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Paragraph 00222; 00223, (2021/12/28)
Provided are novel compounds useful as inhibitors of the KRAS protein, as well as pharmaceutical compositions comprising these compounds and methods of treatment by administration of these compounds or the pharmaceutical compositions.
Cobalt-catalysed C–H methylation for late-stage drug diversification
Ackermann, Lutz,Friis, Stig D.,Johansson, Magnus J.
, p. 511 - 519 (2020/06/05)
The magic methyl effect is well acknowledged in medicinal chemistry, but despite its significance, accessing such analogues via derivatization at a late stage remains a pivotal challenge. In an effort to mitigate this major limitation, we here present a strategy for the cobalt-catalysed late-stage C–H methylation of structurally complex drug molecules. Enabling broad applicability, the transformation relies on a boron-based methyl source and takes advantage of inherently present functional groups to guide the C–H activation. The relative reactivity observed for distinct classes of functionalities were determined and the sensitivity of the transformation towards a panel of common functional motifs was tested under various reaction conditions. Without the need for prefunctionalization or postdeprotection, a diverse array of marketed drug molecules and natural products could be methylated in a predictable manner. Subsequent physicochemical and biological testing confirmed the magnitude with which this seemingly minor structural change can affect important drug properties. [Figure not available: see fulltext.]
Tri-Substituted Triazole-Enabled C-H Activation of Benzyl and Aryl Amines by Iron Catalysis
Shen, Zhigao,Cera, Gianpiero,Haven, Tobias,Ackermann, Lutz
, p. 3795 - 3798 (2017/07/26)
The design of trisubstituted triazoles set the stage for proximity-induced iron-catalyzed C-H activation of benzyl and aryl amines with ample scope. Thereby, C-H alkylations and C-H arylations proved viable with high levels of chemo and positional selectivities by means of racemization-free iron catalysis with the reusable triazole being removed in a traceless fashion.
Conformational Studies by Dynamic NMR. 40. Conformational Atropoisomerism in Highly Hindered Naphthylamines
Davalli, S.,Lunazzi, L.,Macciantelli, D.
, p. 1739 - 1747 (2007/10/02)
N,N-Dialkyl-1-naphthylamines substituted by alkyl groups R (R=Me, Et, i-Pr, t-Bu) in position 2 display anisochronous NMR signals owing to their twisted conformational arrangement.These conformers are enantiomerically related (conformational atropoisomers), and variable temperature NMR measurements allowed the enantiomerization barriers to be determined.The barriers increase with the increasing dimension of the substituents (covering the range 15.7-23.0 kcal mol-1), and the observed trend was reproduced by Molecular Mechanics calculations.The calculations also gaveindications upon the structure of the conformers that correspond to energy minima.The final choice among the possible conformations could be achieved by comparing the computed interprotonic distances with the results of NOE experiments.
