62480-31-3Relevant articles and documents
Switching of macromolecular helicity of optically active poly(phenylacetylene)s bearing cyclodextrin pendants induced by various external stimuli
Maeda, Katsuhiro,Mochizuki, Hiroaki,Watanabe, Masaki,Yashima, Eiji
, p. 7639 - 7650 (2006)
A series of novel phenylacetylenes bearing optically active cyclodextrin (CyD) residues such as α-, β-, and γ-CyD and permethylated β-CyD residues as the pendant groups was synthesized and polymerized with a rhodium catalyst to give highly cis-transoidal
Helical polymer brushes with a preferred-handed helix-sense triggered by a terminal optically active group in the pendant
Maeda, Katsuhiro,Wakasone, Shiho,Shimomura, Kouhei,Ikai, Tomoyuki,Kanoh, Shigeyoshi
, p. 3342 - 3344 (2012)
Helical polymer brushes with a preferred-handed helix-sense composed of a poly(phenylacetylene) backbone and poly(phenyl isocyanate) pendants are synthesized. The helix-sense of the backbone is effectively controlled by the helical chirality of the pendan
Iron-Catalyzed Tertiary Alkylation of Terminal Alkynes with 1,3-Diesters via a Functionalized Alkyl Radical
Tian, Ming-Qing,Shen, Zhen-Yao,Zhao, Xuefei,Walsh, Patrick J.,Hu, Xu-Hong
supporting information, p. 9706 - 9711 (2021/03/19)
Direct oxidative C(sp)?H/C(sp3)?H cross-coupling offers an ideal and environmentally benign protocol for C(sp)?C(sp3) bond formations. As such, reactivity and site-selectivity with respect to C(sp3)?H bond cleavage have remained a persistent challenge. Herein is reported a simple method for iron-catalyzed/silver-mediated tertiary alkylation of terminal alkynes with readily available and versatile 1,3-dicarbonyl compounds. The reaction is suitable for an array of substrates and proceeds in a highly selective manner even employing alkanes containing other tertiary, benzylic, and C(sp3)?H bonds alpha to heteroatoms. Elaboration of the products enables the synthesis of a series of versatile building blocks. Control experiments implicate the in situ generation of a tertiary carbon-centered radical species.
Irreversible Cysteine-Selective Protein Labeling Employing Modular Electrophilic Tetrafluoroethylation Reagents
Václavík, Ji?í,Zschoche, Reinhard,Klimánková, Iveta,Matou?ek, Václav,Beier, Petr,Hilvert, Donald,Togni, Antonio
supporting information, p. 6490 - 6494 (2017/05/15)
Fluoroalkylation reagents based on hypervalent iodine are widely used to transfer fluoroalkyl moieties to various nucleophiles. However, the transferred groups have so far been limited to simple structural motifs. We herein report a reagent featuring a secondary amine that can be converted to amide, sulfonamide, and tertiary amine derivatives in one step. The resulting reagents bear manifold functional groups, many of which would not be compatible with the original synthetic pathway. Exploiting this structural versatility and the known high reactivity toward thiols, the new-generation reagents were used in bioconjugation with an artificial retro-aldolase, containing an exposed cysteine and a reactive catalytic lysine. Whereas commercial reagents based on maleimide and iodoacetamide labeled both sites, the iodanes exclusively modified the cysteine residue. The study thus demonstrates that modular fluoroalkylation reagents can be used as tools for cysteine-selective bioconjugation.
A General Cp*CoIII-Catalyzed Intramolecular C?H Activation Approach for the Efficient Total Syntheses of Aromathecin, Protoberberine, and Tylophora Alkaloids
Lerchen, Andreas,Knecht, Tobias,Koy, Maximilian,Daniliuc, Constantin G.,Glorius, Frank
supporting information, p. 12149 - 12152 (2017/09/13)
Herein, we report a Cp*CoIII-catalyzed C?H activation approach as the key step to create highly valuable isoquinolones and pyridones as building blocks that can readily be applied in the total syntheses of a variety of aromathecin, protoberberine, and tylophora alkaloids. This particular C?H activation/annulation reaction was achieved with several terminal as well as internal alkyne coupling partners delivering a broad scope with excellent functional group tolerance. The synthetic applicability of this protocol reported herein was demonstrated in the total syntheses of two Topo-I-Inhibitors and two 8-oxyprotoberberine cores that can be further elaborated into the tetrahydroprotoberberine and the protoberberine alkaloid core. Moreover these building blocks were also transformed to six different tylophora alkaloids in expedient fashion.
