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1.
Yaping Wang Xinjian Li Faqiang Leng Helong Zhu Jingya Li Dapeng Zou Yangjie Wu Yusheng Wu 《Advanced Synthesis \u0026amp; Catalysis》2014,356(16):3307-3313
An efficient and practical decarboxylative double benzylation method for various 2‐picolinic acids has been established by using a bimetallic catalytic system of palladium(II) chloride (PdCl2) and silver(I) oxide (Ag2O), which offered a variety of diarylmethane derivatives with moderate to good yields.
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Herein a practical and efficient protocol for preparing a range of aminoisoquinolines is reported. Various aminoisoquinolines were prepared in moderate to good yields from the corresponding 2‐methylbenzonitriles and benzonitriles upon treatment with potassium tert‐butoxide.
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Junyu Xu Shihe Hu Yingyan Lu Ying Dong Weifang Tang Tao Lu Ding Du 《Advanced Synthesis \u0026amp; Catalysis》2015,357(5):923-927
A novel synthetic method to access fused indolin‐3‐ones with a tetrasubstituted carbon stereocenter has been developed via NHC‐catalyzed umpolung formal [3+3] cycloaddtion of enals with isatogens. This methodology could be also applied for the quick construction of the 6‐5‐5 tricyclic pyrrolo[1,2‐a]indole skeleton which is frequently found as a core structure of many indole alkaloids.
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Qiang Wang Guifang Han Yuxiu Liu Qingmin Wang 《Advanced Synthesis \u0026amp; Catalysis》2015,357(11):2464-2468
A method for copper‐catalyzed aryltrifluoromethylation of N‐phenylcinnamamides is reported. This method provides a straightforward route to a variety of CF3‐containing 3,4‐dihydroquinolin‐2(1 H)‐ones with excellent regioselectivity and diastereoselectivity.
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The N‐heterocyclic carbene (NHC)‐catalyzed oxidative amidation of aromatic aldehydes with amines in the presence of N‐bromosuccinimide (NBS) as an oxidant has been developed for the synthesis of amides. This amidation strategy is tolerant to both the electronic and the steric nature of the aryl aldehydes employed. The present methodology was extended to chiral amino acid derivatives to generate the corresponding amides in good yields and excellent ee values (>98%).
8.
Olga Bortolini Giancarlo Fantin Valeria Ferretti Marco Fogagnolo Pier Paolo Giovannini Alessandro Massi Salvatore Pacifico Daniele Ragno 《Advanced Synthesis \u0026amp; Catalysis》2013,355(16):3244-3252
The hitherto unreported ability of the methylsulfinyl carbanion (dimsyl anion) to generate acyl anion equivalents is described. The dimsyl anion, in fact, efficiently catalyzes chemoselective intermolecular cross‐benzoin condensations of diaryl α‐diketones (benzils) with various aromatic and aliphatic aldehydes to give the corresponding aryl‐aryl and aryl‐alkyl benzoin benzoates in an atom‐economic fashion. The dimsyl anion acts as an environmentally friendly alternative to the toxic cyanide anion and it is obtained by in situ deprotonation of dimethyl sulfoxide (DMSO) solvent with a catalytic amount of a strong base, potassium tert‐butoxide (t‐BuOK) the optimal promoter. The assumption that the methylsulfinyl carbanion is the active catalyst in the title transformation is supported by electrospray ionization mass spectrometry (ESI‐MS) experiments.
9.
Christine M. M. Hendriks Rebekka A. Bohmann Marina Bohlem Carsten Bolm 《Advanced Synthesis \u0026amp; Catalysis》2014,356(8):1847-1852
A general method for the N‐alkylation of NH‐sulfoximines and NH‐sulfondiimines has been developed, employing alkyl bromides with KOH in DMSO at room temperature. A variety of previously inaccessible N‐alkylated sulfoximines and sulfondiimines was prepared in good to excellent yields (up to 97%). As an application, the conditions were used to access the biologically active Suloxifen.
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Gang Zheng Xiaoli Ma Bangyu Liu Ying Dong Mang Wang 《Advanced Synthesis \u0026amp; Catalysis》2014,356(4):743-748
A metal‐free vinylic carbon‐hydrogen bond thiolation has been developed. Under the catalysis of iodine (10 mol%), the cyclization of α‐alkenoyl ketene dithioacetals afforded a broad range of polyfunctionalized 2‐methylene‐3‐thiophenones in good selectivity with moderate to excellent yields via tandem iodocyclization and dehydroiodination. The synthetic strategy can also be extended to the cyclization of ortho‐methylthiophenyl vinyl ketones leading to 2‐methylene‐3‐benzothiophenones.
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Jianchao Liu Xiaoting Zhang Hui Peng Huanfeng Jiang Biaolin Yin 《Advanced Synthesis \u0026amp; Catalysis》2015,357(4):727-731
Copper chloride‐catalyzed aerobic oxidative annulation of N‐furfuryl‐β‐enaminones provides access to polysubstituted pyrroles and indoles. This protocol involves an unprecedented copper chloride‐catalyzed oxidative chlorination of furan and pyrrole rings with oxygen as the terminal oxidant.
14.
Elumalai Gnanamani Nagamalla Someshwar Jayakumar Sanjeevi Chinnasamy Ramaraj Ramanathan 《Advanced Synthesis \u0026amp; Catalysis》2014,356(10):2219-2223
The conformationally rigid chiral bicyclic skeleton tethered bipyridine N,N′‐dioxide (−)‐ 9 has been designed, synthesized and examined as an organocatalyst in the enantioselective ring opening of meso‐epoxides using tetrachlorosilane (SiCl4). The catalyst (−)‐ 9 is found to exhibit good enantioselectivity for substituted cis‐stilbene epoxides; whereas, the saturated cyclic meso‐epoxides display a moderate enantioselectivity. At −30 °C in chloroform, the catalyst (−)‐ 9 with 0.5 mol % loading generated the chlorohydrins in up to 97 % yield with up to 93 % ee. The possible creation of transient axial chiral environment around hypervalent silicon species due to the presence of conformationally rigid chiral bicyclic skeleton tethered bipyridine N,N′‐dioxide may be responsible for such enantioselectivity observed in the desymmetrization of meso‐epoxides.
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Chuanli Ren Feng Wei Qingqing Xuan Dong Wang Li Liu 《Advanced Synthesis \u0026amp; Catalysis》2016,358(1):132-137
A direct enantioselective reaction of cyclopent‐2‐enone‐derived Morita–Baylis–Hillman alcohols with 4‐hydroxycoumarins has been developed under the catalysis of a chiral primary amine derived from cinchonine in combination with a Brønsted acid. The reaction provides pyranocoumarin products with three vicinal chiral carbon centers in highly regio‐, diastereo‐ and enantioselectivities through a tandem allylic alkylation/intramolecular oxa‐Michael addition.
16.
Qing Xiao Hui Zhu Guangming Li Zhiyuan Chen 《Advanced Synthesis \u0026amp; Catalysis》2014,356(18):3809-3815
The introduction of the (trifluoromethyl)thio moiety into organic molecules has aroused comprehensive interest recently. We describe herein an efficient and chemoselective synthesis of trifluoromethanesulfanylbenzofulvenes through BiCl3‐ or TsOH‐promoted cascade electrophilic cyclization reactions. The presence of the trifluoromethanesulfanyl cation (CF3S+) would facilitate the electrophilic ring closure and nucleophilic attack of chloride or TsOH. This reaction provides a concise method for the synthesis of chlorine‐ or tosyloxy‐substituted trifluoromethanesulfanylbenzofulvenes in good to excellent yields.
17.
Tian He Wen‐Chao Gao Wei‐Kun Wang Chi Zhang 《Advanced Synthesis \u0026amp; Catalysis》2014,356(5):1113-1118
A general and efficient method for the synthesis of oxazolidin‐2‐ones and imidazolidin‐2‐ones directly from 1,3‐diols and 3‐amino alcohols has been developed using the same reagent combination of iodobenzene dichloride (PhICl2) and sodium azide (NaN3).
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Martí Fernndez Magda Parera Teodor Parella Agustí Lled Jean Le Bras Jacques Muzart Anna Pla‐Quintana Anna Roglans 《Advanced Synthesis \u0026amp; Catalysis》2016,358(11):1848-1853
A rhodium‐catalyzed asymmetric synthesis of 5,5‐disubstituted cyclohexa‐1,3‐dienes has been achieved by [2+2+2] cycloaddition reactions between diynes and Morita–Baylis–Hillman (M‐B‐H) adducts as unsaturated substrates. Products containing two adjacent chiral centres (quaternary and tertiary, respectively) were obtained with complete diastereoselectivity and high enantioselectivity (84–97%) through a kinetic resolution of the M‐B‐H adduct. Furthermore, these highly substituted cyclohexadienes reacted with dienophiles to afford the corresponding Diels–Alder cycloadducts in good yields.
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Manoranjan Kumar Richa Sushila Sharma Vinod Bhatt Neeraj Kumar 《Advanced Synthesis \u0026amp; Catalysis》2015,357(13):2862-2868
The first iron(III) chloride‐catalyzed decarboxylative–deaminative functionalization of phenylglycine with o‐substituted nitroarenes was achieved for the synthesis of 4(3H)‐quinazolinones and benzimidazoles. The reaction of 2‐nitrobenzonitrile/2‐nitro‐N,N‐diphenylamine with phenylglycine at 120 °C in the presence of potassium carbonate as a base in toluene generated the products in 45–87% yields. Various functional groups like nitro, fluoride, chloride and trifluoromethyl were well tolerated under the present reaction conditions. In this tandem approach, involvement of transfer hydrogenation of the nitro functionality with in situ generated ammonia, imination, nitrile hydration to amide and oxidative cyclization sequences have been established. The process avoids the use of an external hydrogen source, costly catalysts as well as the isolation of amine and amide intermediates.
20.
David J. Aitken Pierluigi Caboni Hendrik Eijsberg Angelo Frongia Rgis Guillot Jean Ollivier Pier Paolo Piras Francesco Secci 《Advanced Synthesis \u0026amp; Catalysis》2014,356(5):941-945
A catalytic enantioselective synthesis of α‐arylaminocyclobutanones from racemic α‐hydroxycyclobutanone and a selection of N‐alkylanilines has been established, via a tandem condensation/keto‐enol tautomerization process reminiscent of the Amadori and Heyns rearrangements.