150969-54-3Relevant academic research and scientific papers
Iodonium Cation-Pool Electrolysis for the Three-Component Synthesis of 1,3-Oxazoles
Sattler, Lars E.,Hilt, Gerhard
supporting information, p. 605 - 608 (2020/12/07)
The synthesis of 1,3-oxazoles from symmetrical and unsymmetrical alkynes was realized by an iodonium cation-pool electrolysis of I2 in acetonitrile with a well-defined water content. Mechanistic investigations suggest that the alkyne reacts with the acetonitrile-stabilized I+ ions, followed by a Ritter-type reaction of the solvent to a nitrilium ion, which is then attacked by water. The ring closure to the 1,3-oxazoles released molecular iodine, which was visible by the naked eye. Also, some unsymmetrical internal alkynes were tested and a regioselective formation of a single isomer was determined by two-dimensional NMR experiments.
Au(I) Catalyzed Synthesis of Densely Substituted Pyrazolines and Dihydropyridines via Sequential Aza-Enyne Metathesis/6π-Electrocyclization
Sugimoto, Kenji,Kosuge, Shuto,Sugita, Takae,Miura, Yuka,Tsuge, Kiyoshi,Matsuya, Yuji
supporting information, p. 3981 - 3985 (2021/05/26)
A gold(I) autotandem catalysis protocol is reported for the de novo synthesis of densely substituted pyrazolines and dihydropyridines from the corresponding imine derivatives in a highly regioselective fashion via a one-pot aza-enyne metathesis/6π-electrocyclization sequence. The substituents on the nitrogen atom of the imine perfectly control the reaction pathways from the pivotal 1-azabutadiene intermediate; thus, carbazates were converted into pyrazolines via 6π-electrocyclization of α,β-unsaturated hydrazones, while aryl imines provided dihydropyridines via 6π-electrocyclization of 3-azahexatrienes.
Ynonylation of Acyl Radicals by Electroinduced Homolysis of 4-Acyl-1,4-dihydropyridines
Luo, Xiaosheng,Wang, Ping
supporting information, p. 4960 - 4965 (2021/07/20)
Herein we report the conversion of 4-Acyl-1,4-dihydropyridines (DHPs) into ynones under electrochemical conditions. The reaction proceeds via the homolysis of acyl-DHP under electron activation. The resulting acyl radicals react with hypervalent iodine(III) reagents to form the target ynones or ynamides in acceptable yields. This mild reaction condition allows wider functionality tolerance that includes halides, carboxylates, or alkenes. The synthetic utility of this methodology is further demonstrated by the late-stage modification of complex molecules.
Radical Carbonyl Propargylation by Dual Catalysis
Huang, Huan-Ming,Bellotti, Peter,Daniliuc, Constantin G.,Glorius, Frank
supporting information, p. 2464 - 2471 (2020/12/07)
Carbonyl propargylation has been established as a valuable tool in the realm of carbon–carbon bond forming reactions. The 1,3-enyne moiety has been recognized as an alternative pronucleophile in the above transformation through an ionic mechanism. Herein, we report for the first time, the radical carbonyl propargylation through dual chromium/photoredox catalysis. A library of valuable homopropargylic alcohols bearing all-carbon quaternary centers could be obtained by a catalytic radical three-component coupling of 1,3-enynes, aldehydes and suitable radical precursors (41 examples). This redox-neutral multi-component reaction occurs under very mild conditions and shows high functional group tolerance. Remarkably, bench-stable, non-toxic, and inexpensive CrCl3 could be employed as a chromium source. Preliminary mechanistic investigations suggest a radical-polar crossover mechanism, which offers a complementary and novel approach towards the preparation of valuable synthetic architectures from simple chemicals.
Synthesis, Characterization of Spirocyclic λ3-Iodanes and Their Application to Prepare 4,1-Benzoxazepine-2,5-diones and 1,3-Diynes
Sun, Xu,Guo, Xiao-Qiang,Chen, Lian-Mei,Kang, Tai-Ran
supporting information, p. 4312 - 4316 (2021/02/06)
Herein, a [3+2] cycloaddition of aza-oxyallylic cations with ethynylbenziodoxolones for synthesis of new λ3-iodanes containing spirocyclic 4-oxazolidinone has been developed. This cyclic λ3-iodanes display stability in air and excellent solubility in organic solvent. Using them as substrate, both the 4,1-benzoxazepine-2,5-diones and symmetrical 1,3-diynes derivatives were afforded in high yield under copper(I)-catalyzed conditions.
Discotic material hexakis(4-carboxyphenylethynyl)benzene inhibits Escherichia coli growth via the glycolysis pathway
Wu, Hsiu-Hui,Chen, Ho-Lun,Hsu, Chih Ying,Yeh, Chih-Ling,Hsu, Hsiu-Fu,Cheng, Chien-Chung
, p. 239 - 244 (2021/02/01)
Discotic materials and nanoparticles are potential carriers of synthetic chemicals to increase the bioavailability. Several planar discotic compounds were prepared with C–C bond formation by the Sonagoshira reaction. Their toxicity was based on their inhi
From Propargylic Alcohols to Substituted Thiochromenes: Gem-Disubstituent Effect in Intramolecular Alkyne Iodo/hydroarylation
Velasco, Noelia,Suárez, Anisley,Martínez-Lara, Fernando,Fernández-Rodríguez, Manuel ángel,Sanz, Roberto,Suárez-Pantiga, Samuel
supporting information, p. 7078 - 7091 (2021/05/29)
This work describes the 6-endo-dig cyclization of S-aryl propargyl sulfides to afford 2H-thiochromenes. The substitution at the propargylic position plays a crucial role in allowing intramolecular silver-catalyzed alkyne hydroarylation and N-iodosuccinimide-promoted iodoarylation. Additionally, a PTSA-catalyzed thiolation reaction of propargylic alcohols was developed to synthesize the required tertiary S-aryl propargyl ethers. The applicability of merging these two methods is demonstrated by synthesizing the retinoic acid receptor antagonist AGN194310.
Fluoroboron pyrrole liquid crystal compound containing 8-(diphenylethinyl)-ester group flexible multi-element rings, preparation method and application thereof
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Paragraph 0045; 0050-0052, (2019/06/27)
The invention relates to fluoroboron pyrrole liquid crystal dye containing 8-(diphenylethinyl)-ester group flexible multi-element rings, a preparation method and application thereof. According to theinvention, boron fluoride complex dipyrrole methine is used as a matrix, a diphenylacetylene rigid structure is introduced into a No. 8 position through a Sonogashira coupling reaction, a series of BODIPY-type dichroic dye of the 8-methyl-(diphenylethinyl)-ester group flexible multi-element rings is designed and synthetized by connecting bicyclohexyl, cholesterol and other flexible multi-element rings with a diphenyl acetenyl group through an esterification reaction. The maximum emission wavelength of the compound in dichloromethane is all concentrated at about 525nm, so that the compound presents green fluorescence, and a good dichroic ratio and ordered parameters are shown in liquid crystal E7; the liquid crystal compound has a liquid crystal intermediate phase in the temperature range of 100-280 DEG C, and can be used for manufacturing liquid crystal display products, particularly, the liquid crystal compound is used as a guest dye for a guest host mode liquid crystal display; whenthe compound is added to E7 liquid crystal and used in a guest host display mode, the response time can be improved, and the effect of quick response can be achieved.
Catalytic Activation of Trimethylsilylacetylenes: A One-Pot Route to Unsymmetrical Acetylenes and Heterocycles
Lasányi, Dániel,Mészáros, ádám,Novák, Zoltán,Tolnai, Gergely L.
, p. 8281 - 8291 (2018/06/11)
For the synthesis of unsymmetrical acetylenes, a Sonogashira coupling-deprotection-Sonogashira coupling reaction sequence is often used. Removal of protecting groups requires harsh conditions or an excess of difficult to handle and expensive reagents. Herein, we disclose a novel catalytic method for the selective deprotection of trimethylsilylacetylenes in Sonogashira reaction. The reagent hexafluorosilicic acid, an inexpensive nontoxic compound, was used to promote the selective desilylation. This method enables the efficient synthesis of unsymmetric acetylenes with other silylated functional groups present. Further possibilities of the method were explored by synthesis of heterocycles.
Expanding the group of Porous Interpenetrated Zr-Organic Frameworks (PIZOFs) with linkers of different lengths
Lippke, Jann,Brosent, Birte,Von Zons, Tobias,Virmani, Erika,Lilienthal, Sebastian,Preu?e, Thomas,Hulsmann, Miriam,Schneider, Andreas M.,Wuttke, Stefan,Behrens, Peter,Godt, Adelheid
, p. 748 - 761 (2017/01/25)
A Zr-based MOF of the PIZOF type, which consists of two independent and mutually interpenetrating UiO-type frameworks with [Zr6O4(OH)4(O2C)12] nodes, does not only form with a PEPEP dicarboxylic acid (P = phenylene, E = ethynylene). Also dicarboxylic acids with the shorter PPPP and PEPP spacers were found to give PIZOFs, denoted PPPP-PIZOF and PEPP-PIZOF, respectively. Reducing the spacer length even further to a PEEP segment caused a switchover to the formation of a UiO framework. The hysteresis in the Ar sorption curve of PEPP-PIZOF-1 and the slightly too large amount of combustion residue from PPPPPIZOF- 1 suggest structural defects. These hint at a mismatch between the requirement of the optimal linker length for PIZOF formation and the lengths of the PEPP and PPPP dicarboxylates. Nevertheless, these dicarboxylates prefer the formation of a PIZOF over the formation of a UiO structure. PEPEP-PIZOF-2, PPPP-PIZOF-1, and PEPP-PIZOF-1 are stable in air up to 325, 350, and 300 °C, respectively, and have BET surface areas of 2350, 2020, and 1650 m2 g-1, respectively. PEPEP-PIZOFs, even those with very hydrophilic oligo(ethylene glycol) side chains on the linkers, are very stable in water and also during drying from a water-wetted state. On the contrary, PEPP-PIZOF-1 and PPPP-PIZOF-1 that had been exposed to water required exchange of water for ethanol before drying to mostly preserve the framework. The results emphasize the importance of differentiating between framework damage caused through hydrolysis in water and through drying from a water-wetted state. The sensitivity of PEPP-PIZOF-1 and PPPP-PIZOF-1 against drying from a water-wetted state may be the consequence of defects. The drying stability of water-wetted PEPEP-PIZOFs lets us suggest that reversible bending of the linkers contributes to the stability of the PEPEP-PIZOFs.
