Copper-Catalyzed Enantioselective Formal Hydroamination of Oxa- and Azabicyclic Alkenes with Hydrosilanes and Hydroxylamines
摘要:
A CuCl/(R,R)-Ph-BPE-catalyzed enantioselective formal hydroamination of oxa- and azabicyclic alkenes with polymethylhydrosiloxane (PMHS) and O-benzoylhydroxylamines has been developed. The efficient and stereoselective net addition of hydrogen and nitrogen atoms provides the corresponding optically active oxa- and azanorbornenyl- and -norbomanylamines in good yields and good enantiomeric ratios.
乙酸2-硒代氧-2- H-吡啶-1-基酯与苯炔的反应:苯并[ b ]硒代[2,3- b ]吡啶的简便途径
摘要:
苯炔及其3,4,5,6-四苯基,3-和4-甲基,3-甲氧基和4,5-二氟衍生物与乙酸2-硒代氧-2 H-吡啶-1-基酯4a-e反应得到适量收率的苯并[ b ]硒代[2,3- b ]吡啶10-15。苯并炔是通过以下一种或多种方法生成的:用硝酸异戊酯将邻氨基苯甲酸5a-g重氮化;将5a-g邻氨基苯甲酸重氮化。2-重氮碘苯甲酸盐酸盐的温和热分解6a-d处理(苯基)[ o-三氟甲磺酸-((三甲基甲硅烷基)苯基]三氟甲磺酸鎓盐(7);氟化铯制备2-三甲基甲硅烷基苯基三氟甲磺酸酯8a-c。在所有反应中,还获得了相应的2-(甲基硒烯基)吡啶16a-d,表明这些反应可能涉及通过SET(单电子转移)将硒添加到苯炔中。
Trapping σ-Alkyl-Palladium(II) Intermediates with Arynes Encompassing Intramolecular C−H Activation: Spirobiaryls through Pd-Catalyzed Cascade Reactions
作者:Marta Pérez-Gómez、José-Antonio García-López
DOI:10.1002/anie.201607976
日期:2016.11.7
A palladium‐catalyzed cascade reaction based on the trapping of transient alkyl–PdII intermediates with arynes encompassing a C−Hactivation step has been developed. This synthetic pathway gives rise to hetero‐spirocyclic scaffolds containing a biaryl motif, and opens up new synthetic strategies in the design of cascade reactions since it gathers several aspects of Pd chemistry, i.e., intra‐ and intermolecular
Iridium-Catalyzed Asymmetric Ring-Opening of Oxabenzonorbornadienes with Phenols
作者:Hanchao Cheng、Dingqiao Yang
DOI:10.1021/jo3018507
日期:2012.11.2
A novel iridium-catalyzed asymmetricring-opening (ARO) reaction of oxabenzonorbornadienes with a variety of phenols was reported, which afforded the corresponding trans-2-phenoxy-1,2-dihydronaphthalen-1-ol products in high yields with moderate to excellent enantioselectivities (up to 98% ee) under mild conditions. The trans products are formed via the enantioselective cleavage of a bridgehead carbon–oxygen
Preparation of Benzothiopyrano[2,3-b]- indoles by the Reaction of 1,3-Dihydro- indole-2-thiones with Certain Dienophiles
作者:Edward R. Biehl、Sukanta Kamila
DOI:10.3987/com-04-10219
日期:——
Benzothiopyrano[2,3-b]indoles were prepared by the cyclization of 1,3-dihydroindole-2-thiones with various dienophiles. The 1,3-dihydroindole-2-thiones were readily synthesized by the reaction of oxindole with P 2 S 5 followed by a piperidine-mediated condensation of the resulting thioindole with a suitable aromatic aldehyde.
苯并噻吩并[2,3-b]吲哚通过1,3-二氢吲哚-2-硫酮与各种亲双烯体的环化制备。1,3-二氢吲哚-2-硫酮很容易通过羟吲哚与P 2 S 5 的反应合成,然后由哌啶介导的所得硫代吲哚与合适的芳族醛缩合。
practical synthesis of 1,8,13-tribromotriptycene. Reaction with palladium leads to the formation of new pseudo-C3-symmetric carbometalated complexes: namely, Pd(P3T1)Cl and Pd(P3T2)Cl. The catalytic activity of the new ligands and complexes was tested in the palladium-catalyzed chemoselective transferhydrogenation of α,β-unsaturatedketones.
A triptycene-based polymer of intrinsic microposity that displays enhanced surface area and hydrogen adsorption
作者:Bader S. Ghanem、Kadhum J. Msayib、Neil B. McKeown、Kenneth D. M. Harris、Zhigang Pan、Peter M. Budd、Anna Butler、James Selbie、David Book、Allan Walton
DOI:10.1039/b614214a
日期:——
A novel triptycene-based polymer of intrinsic microporosity (Trip-PIM) displays enhanced surface area (1065 m2 g−1) and reversibly adsorbs 1.65% hydrogen by mass at 1 bar/77 K and 2.71% at 10 bar/77 K.