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81.
New tandospirone analogues containing a 1-[3-(trifluoromethyl)phenyl]piperazine (TFMPP) moiety have been synthesized by hydroarylation reactions with Pd(OAc)2. The perhydroisoindole derivatives were obtained by the reaction of reduced starting material with aryl-(heteroaryl) iodides under the same conditions. Spiro-1,3-indandionolylpyrrolidine derivatives having an array of stereocenters are reported. 相似文献
82.
《Tetrahedron》2014,70(52):9814-9818
New process that can selectively prepare α,α-dichloro ketones from various ketones with 1,3-dichloro-5,5-dimethylhydantoin (DCDMH) using ammonium chloride as a catalyst is reported. The effects of ammonium salts, solvents, DCDMH, and reaction temperature were investigated. Under the optimal condition, most of α,α-dichlorinated products were selectively obtained in 86–98% yield. 相似文献
83.
《应用有机金属化学》2017,31(12)
A simple, green and efficient protocol for the one‐pot four‐component synthesis of pyrano[2,3‐c ]pyrazole derivatives produced from reaction between aryl aldehydes, ethyl acetoacetate, malononitrile and hydrazine hydrate in the presence of nano magnetic piperidinium benzene‐1,3‐disulfonate was synthesized in water at 60 °C. The Fe3O4@SiO2 nanoparticle‐supported IL was designed and synthesized. The present process offers advantages such as clean reaction, short reaction time, good to excellent yield, easy purification and easy recoverable catalyst. 相似文献
84.
Hidenori Kinoshita Kazuki Yaguchi Takayuki Tohjima Katsukiyo Miura 《Tetrahedron letters》2017,58(16):1607-1610
The diisobutylaluminum hydride (DIBAL-H)-promoted benzocyclization, recently developed by this group, was adopted for the synthesis of a natural product containing a 9,10-dihydrophenanthrene skeleton to demonstrate its synthetic utility. One of the extracts from the roots of Salvia hydrangea DC. ex Bentham (Lamiaceae), a 20-norabietane derivative, was selected as the target molecule. The key step forming the 9,10-dihydrophenanthrene skeleton was achieved by the DIBAL-H-promoted cyclization of a silylated 1,3-dien-5-yne easily accessible from a substituted α-tetralone. 相似文献
85.
Venkata Reddy Regalla RamaKrishnam Raju Addada Venkat Swami Puli Abhishek S. Saxena Anindita Chatterjee 《Tetrahedron letters》2017,58(24):2344-2346
A short and efficient method for the stereoselective synthesis of Dendrodolide L has been developed from inexpensive and commercially available starting material. This convergent synthesis utilizes Jacobsen kinetic resolution, regioselective ring-opening of epoxide and Yamaguchi macrolactonization as key steps. 相似文献
86.
S. R. Jayapradha S. Muthusubramanian 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1):32-38
Abstract The synthesis of a new set of 2,3,4,5-substituted isoxazolidines having a sulfur containing heterocyclic moiety has been described. The structural features of the compounds have been analyzed by 1H and 13C NMR spectroscopy as well as by single crystal X-ray studies. [Supplemental materials are available for this article. Go to the publisher's online edition of Phosphorus, Sulfur, and Silicon and the Related Elements for the following free supplemental resource: .cif file.] 相似文献
87.
Abdolali Alizadeh Sadegh Rostamnia Qasem Oskueyan 《Phosphorus, sulfur, and silicon and the related elements》2013,188(7):1779-1784
Heterocyclic systems 4,5-dihydrothiazol-2-ylamine derivatives are synthesized via an intramolecular thioiminoformamide annulation reaction. 相似文献
88.
《Phosphorus, sulfur, and silicon and the related elements》2013,188(12):2597-2607
New heterocyclic systems have been prepared by 1,3-dipolar cycloaddition reactions on the 11-allylsulfanylpyrrolo[2,1-c] [1,4] benzodiazépine-5-thione 3. The synthesized compounds contain in their structures the pyrrolobenzodiazépine spiro-connected to the thiadiazole. 相似文献
89.
D. D. Enchev 《Phosphorus, sulfur, and silicon and the related elements》2013,188(9):2137-2140
Abstract The preparation of the titled compounds have been reported. The five-membered heterocyclization reaction of these compounds in the reaction with phosphorus-containing pseudohalogenes have been discussed. 相似文献
90.
Sabine Ebeling Dieter Matthies Daniel McCarthy 《Phosphorus, sulfur, and silicon and the related elements》2013,188(3-4):265-273
Abstract α-Amidoalkylation of allyttrimethylsilane with methyl-2-chloro-2-(p-chlorobenzoylamino)-ethanoate 1 gave in the presence of Lewis acid racemic methyl-2- (p-chlorobenzoylamino)-4-penteno ate 2. Under the same conditions, vinlytrimethylsilane afforded (±)-trans-2-(p-chlorophenyl)-5,6-dihydro-4-methoxycarbonyl-6-trimethylsilyl-4H-1, 3-oxazine 4 as the major, by n.m.r. data and x-ray crystallography established product. 相似文献