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991.
Textile/Metal–Organic‐Framework Composites as Self‐Detoxifying Filters for Chemical‐Warfare Agents 下载免费PDF全文
Elena López‐Maya Dr. Carmen Montoro Dr. L. Marleny Rodríguez‐Albelo Dr. Salvador D. Aznar Cervantes Dr. A. Abel Lozano‐Pérez Prof. José Luis Cenís Dr. Elisa Barea Prof. Jorge A. R. Navarro 《Angewandte Chemie (International ed. in English)》2015,54(23):6790-6794
The current technology of air‐filtration materials for protection against highly toxic chemicals, that is, chemical‐warfare agents, is mainly based on the broad and effective adsorptive properties of hydrophobic activated carbons. However, adsorption does not prevent these materials from behaving as secondary emitters once they are contaminated. Thus, the development of efficient self‐cleaning filters is of high interest. Herein, we report how we can take advantage of the improved phosphotriesterase catalytic activity of lithium alkoxide doped zirconium(IV) metal–organic framework (MOF) materials to develop advanced self‐detoxifying adsorbents of chemical‐warfare agents containing hydrolysable P? F, P? O, and C? Cl bonds. Moreover, we also show that it is possible to integrate these materials onto textiles, thereby combining air‐permeation properties of the textiles with the self‐detoxifying properties of the MOF material. 相似文献
992.
Wen Shao He Li Chuan Liu Prof. Dr. Chen‐Jiang Liu Prof. Dr. Shu‐Li You 《Angewandte Chemie (International ed. in English)》2015,54(26):7684-7687
The first copper‐catalyzed intermolecular dearomatization of indoles by an asymmetric propargylic substitution reaction was developed. This method provides a highly efficient synthesis of versatile furoindoline and pyrroloindoline derivatives containing a quaternary carbon stereogenic center and a terminal alkyne moiety with up to 86 % yield and 98 % ee. 相似文献
993.
Inside Cover: Textile/Metal–Organic‐Framework Composites as Self‐Detoxifying Filters for Chemical‐Warfare Agents (Angew. Chem. Int. Ed. 23/2015) 下载免费PDF全文
994.
Jeffrey J. Jackson Dr. Hiroyuki Kobayashi Sophia D. Steffens Prof. Dr. Armen Zakarian 《Angewandte Chemie (International ed. in English)》2015,54(34):9971-9975
The asymmetric synthesis of dragmacidin D ( 1 ) was completed in 10 steps. Its sole stereocenter was set by using direct asymmetric alkylation enabled by a C2‐symmetric tetramine and lithium N‐(trimethylsilyl)‐tert‐butylamide as the enolization reagent. A central Larock indole synthesis was employed in a convergent assembly of the heterocyclic subunits. The stereochemical evidence from this work strongly supports the predicted S configuration at the 6′′′ position, which is consistent with other members of the dragmacidin family of natural products. 相似文献
995.
Self‐Pillared,Single‐Unit‐Cell Sn‐MFI Zeolite Nanosheets and Their Use for Glucose and Lactose Isomerization 下载免费PDF全文
Dr. Limin Ren Dr. Qiang Guo Prashant Kumar Marat Orazov Dandan Xu Prof. Saeed M. Alhassan Prof. K. Andre Mkhoyan Prof. Mark E. Davis Prof. Michael Tsapatsis 《Angewandte Chemie (International ed. in English)》2015,54(37):10848-10851
Single‐unit‐cell Sn‐MFI, with the detectable Sn uniformly distributed and exclusively located at framework sites, is reported for the first time. The direct, single‐step, synthesis is based on repetitive branching caused by rotational intergrowths of single‐unit‐cell lamellae. The self‐pillared, meso‐ and microporous zeolite is an active and selective catalyst for sugar isomerization. High yields for the conversion of glucose into fructose and lactose to lactulose are demonstrated. 相似文献
996.
Hydroxoiridium/Chiral Diene Complexes as Effective Catalysts for Asymmetric Annulation of α‐Oxo‐ and Iminocarboxamides with 1,3‐Dienes 下载免费PDF全文
Miyuki Hatano Dr. Takahiro Nishimura 《Angewandte Chemie (International ed. in English)》2015,54(37):10949-10952
The asymmetric [3+2] annulation of α‐oxo‐ and α‐iminocarboxamides with 1,3‐dienes catalyzed by hydroxoiridium/chiral diene complexes was realized, giving high yields of the corresponding γ‐lactams with high enantioselectivity. 相似文献
997.
Regio‐ and Enantioselective Aza‐Diels–Alder Reactions of 3‐Vinylindoles: A Concise Synthesis of the Antimalarial Spiroindolone NITD609 下载免费PDF全文
Haifeng Zheng Prof. Dr. Xiaohua Liu Chaoran Xu Yong Xia Dr. Lili Lin Prof. Dr. Xiaoming Feng 《Angewandte Chemie (International ed. in English)》2015,54(37):10958-10962
An asymmetric aza‐Diels–Alder reaction of 3‐vinylindoles with isatin‐derived ketimines has been developed. A series of spiroindolone derivatives were thus obtained in good to excellent yields with excellent enantioselectivity (up to 96 % yield and 99 % ee). Furthermore, the antimalarial compound NITD609 could be obtained in three steps with an overall yield of 40.6 %. Control experiments and operando IR experiments imply a concerted reaction pathway. The regioselectivity and exo selectivity result from π–π interactions between the two indoline rings of the two reactants. 相似文献
998.
Selective Photooxidation of a Mustard‐Gas Simulant Catalyzed by a Porphyrinic Metal–Organic Framework 下载免费PDF全文
Dr. Yangyang Liu Dr. Ashlee J. Howarth Prof. Joseph T. Hupp Prof. Omar K. Farha 《Angewandte Chemie (International ed. in English)》2015,54(31):9001-9005
The photooxidation of a mustard‐gas simulant, 2‐chloroethyl ethyl sulfide (CEES), is studied using a porphyrin‐based metal–organic framework (MOF) catalyst. At room temperature and neutral pH value, singlet oxygen is generated by PCN‐222/MOF‐545 using an inexpensive and commercially available light‐emitting diode. The singlet oxygen produced by PCN‐222/MOF‐545 selectively oxidizes CEES to the comparatively nontoxic product 2‐chloroethyl ethyl sulfoxide (CEESO) without formation of the highly toxic sulfone product. In comparison to current methods, which utilize hydrogen peroxide as an oxidizing agent, this is a more realistic, convenient, and effective method for mustard‐gas detoxification. 相似文献
999.
Catalytic Asymmetric 1,6‐Conjugate Addition of para‐Quinone Methides: Formation of All‐Carbon Quaternary Stereocenters 下载免费PDF全文
Dr. Zhaobin Wang Yuk Fai Wong Prof. Jianwei Sun 《Angewandte Chemie (International ed. in English)》2015,54(46):13711-13714
Described herein is a general and mild catalytic asymmetric 1,6‐conjugate addition of para‐quinone methides (p‐QMs), a class of challenging reactions with previous limited success. Benefiting from chiral Brønsted acid catalysis, which allows in situ formation of p‐QMs, our reaction expands the scope to general p‐QMs with various substitution patterns. It also enables efficient intermolecular formation of all‐carbon quaternary stereocenters with high enantioselectivity. 相似文献
1000.
Crystal Structure of the Isopropylzinc Alkoxide of Pyrimidyl Alkanol: Mechanistic Insights for Asymmetric Autocatalysis with Amplification of Enantiomeric Excess 下载免费PDF全文
Dr. Arimasa Matsumoto Takaaki Abe Atsushi Hara Takayuki Tobita Taisuke Sasagawa Prof. Dr. Tsuneomi Kawasaki Prof. Dr. Kenso Soai 《Angewandte Chemie (International ed. in English)》2015,54(50):15218-15221
Asymmetric amplification during self‐replication is a key feature that is used to explain the origin of homochirality. Asymmetric autocatalysis of pyrimidyl alkanol in the asymmetric addition of diisopropylzinc to pyrimidine‐5‐carbaldehyde is a unique example of this phenomenon. Crystallization of zinc alkoxides of this 5‐pyrimidyl alkanol and single‐crystal X‐ray diffraction analysis of the alkoxide crystals reveal the existence of tetramer or higher oligomer structures in this asymmetric autocatalytic system. 相似文献