1195-14-8Relevant articles and documents
Synthesis of Chiral Polycyclic Tetrahydrocarbazoles by Enantioselective Aminocatalytic Double Activation of 2-Hydroxycinnamaldehydes with Dienals
Ming, Yong-Chao,Lv, Xue-Jiao,Liu, Ming,Liu, Yan-Kai
, p. 6515 - 6519 (2021)
An efficient aminocatalytic enantioselective double-activation strategy has been developed that combines several different aminocatalytic modes in a cascade process, such as iminium ion, vinylogous iminium ion, trienamine, and dienamine activations. By using this strategy, 2-hydroxycinnamaldehydes worked well with various dienals via [4 + 2] cycloaddition and the oxa-Michael reaction-initiated cascade, respectively, leading to chiral polycyclic tetrahydrocarbazole and chromane derivatives with excellent diastereo- and enantioselectivities.
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Ando et al.
, p. 704 (1975)
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Synthesis and photochromic properties of functional diarylethenes with a [1,3]dithiol-2-one (Thione) bridging unit
Impagnatiello,Heynderickx,Moustrou,Samat
, p. 243 - 248 (2005)
In designing new photochromic compounds for optical data storage and photoswitching devices, the synthesis of a series of 4,5-diaryl-1,3-dithiol-2- one and 4,5-diaryl-1,3-dithiol-2-thione, which are suitable building blocks for incorporation with fluorophore, is herein reported. Our strategy needs the preliminary preparation of diarylalkynes, obtained by successive Sonogashira-Hagihara coupling-reactions in good yields (63-92%). A combination of these synthetic precursors with diisopropylxanthogen disulfide leads to the corresponding 4,5-diaryl-1,3-dithiol-2-ones under radical conditions with excellent yields (54-70%). The thionation of these compounds is obtained nearly quantitatively with phosphorous pentasulfide.
Regiochemical selectivity in the Carbon-Sulfur bond cleavage of 2-methylbenzothiophene: Synthesis, characterization, and mechanistic study of reversible insertion into a C-S bond
Myers, Andrew W.,Jones, William D.,McClements, Shawn M.
, p. 11704 - 11709 (1995)
Thermolysis of (C5Me5)Rh(PMe3)(Ar)(H) (Ar = Ph or 3,5-xylyl) with 2-methylbenzothiophene at early reaction times yields a C-H activation compound and a single C-S insertion product resulting from insertion of rhodium into the S-C bond adjacent to the methyl substituent, 2k. Prolonged heating results in the conversion of 2k to the isomer in which the metal has inserted into the C-S bond adjacent to the aryl group via an intramolecular pathway, 2t. Both 2k and 2t were characterized by 1H, 31P, and 13C NMR spectroscopies and by single crystal X-ray diffraction. The kinetic product crystallized as a racemic twin in the orthorhombic space group P212121, with a = 8.5438(1) ?, b = 12.8079(2) ?, c = 19.3021(3) ?, Z = 4, and V = 2112.19(5) ?3, while the thermodynamic product crystallized in the triclinic space group P1 with a = 8.669(6) ?, b = 8.86(1) ?, c = 15.8(1) ?, α = 76.42(9)°, β = 86.66(7)°, γ = 74.46(9)°, Z = 2, and V = 1091.5(1.9) ?3.
A new Zn/TiCl4/LiAlH4 mediated approach to 2-aryl- or 2-alkyl-substituted benzothiophenes via intramolecular cyclization
Hyung, Jae Jeong,Un, Young Yoon,Sang, Hun Jang,Yoo, Un-Aeh,Su, Nam Kim,Ba, Tai Truong,Sung, Chul Shin,Yoon, Yong-Jin,Okram, Mukherjee Singh,Lee, Sang-Gyeong
, p. 1407 - 1410 (2007)
Methyl 2-(substituted benzoylthio)benzoates undergo intramolecular ring cyclizations in the presence of Zn/TiCl4/LiAlH4 to give the corresponding 2-aryl- or alkylsubstituted benzothiophenes in good yields. Georg Thieme Verlag Stuttgart.
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Shchedrinskaya et al.
, (1973)
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Metal-directed synthesis of quadruple-stranded helical Eu(iii) molecular switch: A significant improvement in photocyclization quantum yield
Gao, Ting,Li, Hongfeng,Yan, Pengfei,Zhang, Yuan,Zhou, Yanyan
supporting information, p. 13213 - 13216 (2020/11/09)
The self-assembly of a quadruple-stranded Eu(iii) helicate induces the conformation transformation of a DAE-based photochromic ligand from parallel to antiparallel, which brings a significant improvement in the photocyclization quantum yield (Φo-c) as compared with the free ligand. Furthermore, the photocontrolled open- and closed-rings of the ligand realized a reversible modulation toward Eu3+ center emission.
A methylation platform of unconventional inert aryl electrophiles: Trimethylboroxine as a universal methylating reagent
Feng, Boya,Yang, Yudong,You, Jingsong
, p. 6031 - 6035 (2020/07/10)
Methylation is one of the most fundamental conversions in medicinal and material chemistry. Extension of substrate types from aromatic halides to other unconventional aromatic electrophiles is a highly important yet challenging task in catalytic methylation. Disclosed herein is a series of transition metal-catalyzed methylations of unconventional inert aryl electrophiles using trimethylboroxine (TMB) as the methylating reagent. This transformation features a broad substrate type, including nitroarenes, benzoic amides, benzoic esters, aryl cyanides, phenol ethers, aryl pivalates and aryl fluorides. Another important merit of this work is that these widespread "inert"functionalities are capable of serving as directing or activating groups for selective functionalization of aromatic rings before methylation, which greatly expands the connotation of methylation chemistry.
