93296-09-4Relevant academic research and scientific papers
Water-Soluble Phospholo[3,2-b]phosphole-P,P′-Dioxide-Based Fluorescent Dyes with High Photostability
Wang, Chenguang,Fukazawa, Aiko,Tanabe, Yoshiyuki,Inai, Naoto,Yokogawa, Daisuke,Yamaguchi, Shigehiro
, p. 1616 - 1624 (2018)
We recently reported that fluorescent dye PB430, which consisted of a 2-phenyl-substituted benzophosphole P-oxide skeleton that was reinforced by a methylene bridge, showed pronounced photostability and, thus, high utility for applications in super-resolution stimulated emission depletion (STED) microscopy. Herein, we replaced the methylene bridge with another P=O group to 1) investigate the role of the bridging moieties; and 2) further modulate the fluorescence properties of this skeleton. We synthesized a series of phospholo[3,2-b]phosphole-based dyes—trans-PO-PB430, cis-PO-PB430, and trans-PO-PB460—all of which showed sufficient water solubility. Moreover, trans-PO-PB430 and trans-PO-PB460 exhibited intense green and orange fluorescence, respectively, and a high photostability that was comparable to that of PB430. In contrast, cis-PO-PB430 underwent rapid photobleaching upon continuous photoirradiation, which demonstrated the importance of steric shielding of the polycyclic skeleton by the substituents on the bridging moieties. The fluorescence properties of these dyes were insensitive to concentration, pH value, and polarity changes of the environment in solution. In addition, even in the solid state, these dyes showed strong green to orange emissions. These results demonstrate the potential utility of trans-PO-PB430 and trans-PO-PB460 as highly photostable fluorescent dyes.
Ni-Catalyzed Synthesis of Thiocarboxylic Acid Derivatives
Monteith, John J.,Scotchburn, Katerina,Mills, L. Reginald,Rousseaux, Sophie A. L.
supporting information, p. 619 - 624 (2022/01/20)
A Ni-catalyzed cross-coupling of readily accessible O-alkyl xanthate esters or thiocarbonyl imidazolides and organozinc reagents for the synthesis of thiocarboxylic acid derivatives has been developed. This method benefits from a fast reaction time, mild reaction conditions, and ease of starting material synthesis. The use of transition-metal catalysis to access a diverse range of thiocarbonyl-containing compounds provides a useful complementary approach when compared with previously established methodologies.
Enantiomerically Enriched α-Borylzinc Reagents by Nickel-Catalyzed Carbozincation of Vinylboronic Esters
Chen, Jingjia,Hu, Weipeng,Jin, Jing,Lovinger, Gabriel J.,Morken, James P.,Zhang, Chenlong
supporting information, p. 14189 - 14195 (2021/09/11)
In this paper is described a synthesis of enantiomerically enriched, configurationally stable organozinc reagents by catalytic enantioselective carbozincation of a vinylboronic ester. This process furnishes enantiomerically enriched α-borylzinc intermediates that are shown to undergo stereospecific reactions, producing enantioenriched secondary boronic ester products. The properties of the intermediate α-borylzinc reagent are probed and the synthetic utility of the products is demonstrated by application to the synthesis of (-)-aphanorphine and (-)-enterolactone.
The Formation of P-C Bonds Utilizing Organozinc Reagents for the Synthesis of Aryl- A nd Heteroaryl-Dichlorophosphines
Kirst, Christin,Tietze, Jonathan,Ebeling, Marian,Horndasch, Lukas,Karaghiosoff, Konstantin
, p. 17337 - 17343 (2021/11/18)
Aryl- A nd heteroaryl-dichlorophosphines are mildly and selectively made in a one-pot synthesis in moderate to good yields starting from the respective aryl bromides or five-membered heterocycles, following lithiation with nBuLi, transmetalation with ZnCl
Ni-Catalyzed C(sp3)–O Arylation of α-Hydroxy Esters
Monteith, John J.,Rousseaux, Sophie A. L.
supporting information, p. 9485 - 9489 (2021/12/09)
A Negishi cross-coupling of α-hydroxy ester derivatives and arylzinc reagents has been developed. This reaction tolerates both primary and secondary C(sp3)–O alcohol precursors and achieves efficient cross-coupling under Ni catalysis without the need for added external metal reductant, photocatalyst, or additives. The arylation of readily accessible C(sp3)–O electrophiles in this operationally simple, rapid, and mild reaction provides a complementary way of accessing desirable α-aryl ester products.
Palladium-catalyzed secondary benzylic imidoylative reactions
Wang, Chenglong,Wu, Licheng,Xu, Wentao,He, Feng,Qu, Jingping,Chen, Yifeng
supporting information, p. 6954 - 6959 (2020/09/15)
Reported herein is a palladium-catalyzed secondary benzylic imidoylative Negishi reaction leveraging the sterically bulky aromatic isocyanides as the imine source. This method allows the facile access of alkyl-, (hetero)aryl-, and alkynylzinc reagents to afford various α-substituted phenylacetone products under mild acidic hydrolysis, which are ubiquitous motifs in many pharmaceuticals and biologically active compounds. The diastereoselective reduction of imine can be accomplished to provide the expedient conversion of secondary benzylic halide into α-substituted phenethylamine derivatives with high atom economy.
Asymmetric Synthesis of Alkylzincs by Rhodium-Catalyzed Enantioselective Arylative Cyclization of 1,6-Enynes with Arylzincs
Chen, Jiahua,Hayashi, Tamio
supporting information, p. 18510 - 18514 (2020/08/21)
A chiral diene-rhodium complex was found to catalyze the reaction of 1,6-enynes with ArZnCl to give high yields of 2-(alkylidene)cyclopentylmethylzincs with high enantioselectivity (95–99 % ee). The enantioenriched alkylzincs were readily converted in a one-pot approach into a wide variety of functionalized products by taking advantage of their unique reactivity. The catalytic cylcle involves arylrhodation of alkyne, intramolecular alkenylrhodation of alkene, and transmetalation of the alkyl-rhodium intermediate into alkylzinc.
Direct Umpolung Morita–Baylis–Hillman like α-Functionalization of Enones via Enolonium Species
Arava, Shlomy,Kapanaiah, Raja,Pathe, Gulab K.,Santra, Sourav K.,Szpilman, Alex M.
supporting information, p. 15171 - 15175 (2020/07/04)
Herein we report on the umpolung of Morita–Baylis–Hillman type intermediates and application to the α-functionalization of enone C?H bonds. This reaction gives direct access to α-chloro-enones, 1,2-diketones and α-tosyloxy-enones. The latter are important intermediates for cross-coupling reaction and, to the best of our knowledge, cannot be made in a single step from enones in any other way. The proposed mechanism is supported by spectroscopic studies. The key initial step involves conjugate attack of an amine (DABCO or pyridine), likely assisted by hypervalent iodine acting as a Lewis acid leading to formation of an electrophilic β-ammonium-enolonium species. Nucleophilic attack by acetate, tosylate, or chloride anion is followed by base induced elimination of the ammonium species to give the noted products. Hydrolysis of α-acetoxy-enones lead to formation of 1,2-diketones. The α-tosyl-enones participate in Negishi coupling reactions under standard conditions.
Copper-Catalyzed Electrophilic Thiolation of Organozinc Halides by Using N-Thiophthalimides Leading to Polyfunctional Thioethers
Gra?l, Simon,Hamze, Clémence,Koller, Thadd?us J.,Knochel, Paul
supporting information, p. 3752 - 3755 (2019/02/13)
(Hetero)aryl, benzylic, and alkyl zinc halides were thiolated with N-thiophthalimides at 25 °C within 1 h in the presence of 5–10 % Cu(OAc)2?H2O to furnish the corresponding polyfunctionalized thioethers in good yields. This electrop
Modular Functionalization of Arenes in a Triply Selective Sequence: Rapid C(sp2) and C(sp3) Coupling of C?Br, C?OTf, and C?Cl Bonds Enabled by a Single Palladium(I) Dimer
Keaveney, Sinead T.,Kundu, Gourab,Schoenebeck, Franziska
supporting information, p. 12573 - 12577 (2018/09/18)
Full control over multiple competing coupling sites would enable straightforward access to densely functionalized compound libraries. Historically, the site selection in Pd0-catalyzed functionalizations of poly(pseudo)halogenated arenes has been unpredictable, being dependent on the employed catalyst, the reaction conditions, and the substrate itself. Building on our previous report of C?Br-selective functionalization in the presence of C?OTf and C?Cl bonds, we herein complete the sequence and demonstrate the first general arylations and alkylations of C?OTf bonds (in I dimer. This allowed the realization of the first general and triply selective sequential C?C coupling (in 2D and 3D space) of C?Br followed by C?OTf and then C?Cl bonds.
