[EN] SILOLE-BASED MONOMERS AND POLYMERS FOR ORGANIC LIGHT-EMITTING DIODE DEVICES [FR] MONOMÈRES À BASE DE SILOLE ET POLYMÈRES POUR DISPOSITIFS À DIODES ÉLECTROLUMINESCENTES ORGANIQUES
Preparation of 3-O-aryl chloramphenicol derivatives via chemoselective copper-catalyzed O-arylation of (1R,2R)-(−)-N-BOC-2-amino-1-(4-nitrophenyl)-1,3-propanediol using triarylbismuthines
A copper-catalyzed protocol for the chemoselective arylation of (1R,2R)-(−)-N-BOC-2-amino-1-(4-nitrophenyl)-1,3-propanediol using triarylbismuth reagents is reported. The reaction operates under simple and mild conditions, shows good functional group tolerance and allows the installation of ortho-, meta-, and para-substituted aryl groups in moderate to good yields. These arylated products are then
报道了使用三芳基铋试剂的(1 R,2 R)-(-)- N -BOC-2-氨基-1-(4-硝基苯基)-1,3-丙二醇化学选择性芳基化的铜催化方案。该反应在简单和温和的条件下进行,显示出良好的官能团耐受性,并允许以中等至良好的产率安装邻,间和对取代的芳基。然后将这些芳基化产物分两步转化为其相应的N-二氯乙酰胺衍生物。该序列提供了对3- O-芳基氯霉素衍生物的方便访问。
A facile and efficient synthesis of new fluoroalkylsulfonates and the corresponding tetrabutylammonium salts
作者:Youbing Mu、Xiaobo Wan
DOI:10.1016/j.tetlet.2019.150966
日期:2019.8
A useful synthetic methodology towards new fluoroalkylsulfonates was developed. Grignard addition to an inexpensive and commercially available fluorine-containing ester, methyl 2,2-difluoro-2-(fluorosulfonyl)acetate (1) gave the mono-adduct (2) as the only product in high yield. The scope and limitation of this method were thoroughly investigated and it was found that it works for most Grignard reagents
Structure-activity relationships in the 2-arylcarbapenem series. Synthesis of 1-methyl-2-arylcarbapenems
作者:Ravindra Nath Guthikonda、L. D. Cama、M. Quesada、M. F. Woods、T. N. Salzmann、B. G. Christensen
DOI:10.1021/jm00388a022
日期:1987.5
tert-butyldimethylsilyl esters of the azetidinones 6-8b served as the crucial synthons in the preparation of the potentially useful ylide pyridyl thio esters 18-20. These intermediates were utilized to synthesize a host of title carbapenems 25-30d, 32, and 49-53. The antimicrobial properties and DHP-I susceptibility of these carbapenems were studied with reference to thienamycin.
Organocatalytic Asymmetric Synthesis of 1,1-Diarylethanes by Transfer Hydrogenation
作者:Zhaobin Wang、Fujin Ai、Zheng Wang、Wanxiang Zhao、Guangyu Zhu、Zhenyang Lin、Jianwei Sun
DOI:10.1021/ja510980d
日期:2015.1.14
organocatalytic transferhydrogenation strategy for the asymmetric synthesis of 1,1-diarylethanes is described. Under mild conditions, a range of 1,1-diarylethanes substituted with an o-hydroxyphenyl or indole unit could be obtained with excellent efficiency and enantioselectivity. We also extended the protocol to an unprecedented asymmetric hydroarylation of 1,1-diarylalkenes with indoles for the synthesis of
Cobalt(diamine)-Catalyzed Cross-coupling Reaction of Alkyl Halides with Arylmagnesium Reagents: Stereoselective Constructions of Arylated Asymmetric Carbons and Application to Total Synthesis of AH13205
A cobalt-diamine complex catalyzes the cross-couplingreactions of primary and secondary alkyl halides with aryl Grignard reagents. It is confirmed that oxidative addition of alkyl halide to cobalt proceeds via a radical process. Optically pure Ueno-Stork halo acetals undergo diastereoselective cross-couplingreactions, the products of which are transformed into optically active THF derivatives. A