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Dr. Kai‐Oliver Feldmann Dr. Thomas Wiegand Dr. Jinjun Ren Prof. Dr. Hellmut Eckert Joachim Breternitz Matthias F. Groh Ulrike Müller Prof. Dr. Michael Ruck Dr. Boris Maryasin Prof. Dr. Christian Ochsenfeld Dr. Oliver Schön Prof. Dr. Konstantin Karaghiosoff Prof. Dr. Jan J. Weigand 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(27):9697-9712
Although a fairly large number of binary group 15/16 element cations have been reported, no example involving phosphorus in combination with a group 16 element has been synthesized and characterized to date. In this contribution is reported the synthesis and structural characterization of the first example of such a cation, namely a nortricyclane‐type [P3Se4]+. This cation has been independently discovered by three groups through three different synthetic routes, as described herein. The molecular and electronic structure of the [P3Se4]+ cage and its crystal properties in the solid state have been characterized comprehensively by using X‐ray diffraction, Raman, and nuclear magnetic resonance spectroscopies, as well as quantum chemical calculations. 相似文献
989.
Diversity in Gold‐Catalyzed Formal Cycloadditions of Ynamides with Azidoalkenes or 2H‐Azirines: [3+2] versus [4+3] Cycloadditions 下载免费PDF全文
Samir Kundlik Pawar Rajkumar Lalji Sahani Prof. Dr. Rai‐Shung Liu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(30):10843-10850
Gold‐catalyzed cycloadditions of ynamides with azidoalkenes or 2H‐azirines give [3+2] or [4+3] formal cycloadducts of three classes. Cycloadditions of ynamides with 2H‐azirine species afford pyrrole products with two regioselectivities when the Cβ‐substituted 2H‐azirine is replaced from an alkyl (or hydrogen) with an ester group. For ynamides substituted with an electron‐rich phenyl group, their reactions with azidoalkenes proceed through novel [4+3] cycloadditions to deliver 1H‐benzo[d]azepine products instead. 相似文献
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Highly Antiplasmodial Non‐Natural Oxidative Products of Dioncophylline A: Synthesis,Absolute Configuration,and Conformational Stability 下载免费PDF全文
Yasmin Hemberger Dr. Guoliang Zhang Prof. Dr. Reto Brun Marcel Kaiser Prof. Dr. Gerhard Bringmann 《Chemistry (Weinheim an der Bergstrasse, Germany)》2015,21(41):14507-14518
Four new compounds, the monomeric dioncotetralones A ( 6 a ) and B ( 6 b ) and the dimeric compounds jozimine A3 ( 7 ) and jozimine A4 ( 9 ), were semi‐synthesized from the natural product dioncophylline A ( 4 ) and its 5′‐O‐demethylated derivative ( 5 ), respectively, under phenol oxidative reaction conditions. Dioncotetralones A ( 6 a ) and B ( 6 b ) possess an unprecedented Z‐configured double bond, in contrast to the classic biaryl axis that is present in the precursor dioncophylline A ( 4 ), and an additional stereogenic center at the C2′ atom was generated due to the dearomatization. The resulting steric repulsion forced the expected planar double bond into a helical distorted conformation. The homocoupling of 5 yielded compounds 7 and 9 , the latter of which is the first sp3–sp2 coupled product of a monomeric naphthylisoquinoline with a reduced one and, thus, contains a newly generated stereogenic center. The full stereostructures of 6 a , 6 b , 7 , and 9 were successfully elucidated by the interplay of spectroscopic methods (1D/2D NMR and electronic circular‐dichroism spectroscopy) in combination with quantum‐chemical calculations. In addition, compounds 6 a and 7 exhibited high antiplasmodial activities with excellent half‐maximal inhibitory concentration values. 相似文献