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检索条件"机构=Department of Chemistry"
809885 条 记 录,以下是1-10 订阅
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A new strategy for extending N-acyl imides as chiral auxiliaries for aldol and Diels-Alder reactions: Application to an enantioselective synthesis of alpha-himachalene
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Angew. Chem. Int. Ed. Engl. 1997年 第19期36卷 2119-2121页
作者: Evans, DA Ripin, DHB Johnson, JS Shaughnessy, EA Department of Chemistry and Chemical Biology Harvard University Cambridge MA 02138 (USA) Fax: Int. code +(617)495-1460 e-mail: evans@chemistry.harvard.edu Department of Chemistry and Chemical Biology Harvard University Cambridge MA 02138 (USA) Fax: Int. code +(617)495-1460 e-mail: evans@chemistry.harvard.edu Department of Chemistry and Chemical Biology Harvard University Cambridge MA 02138 (USA) Fax: Int. code +(617)495-1460 e-mail: evans@chemistry.harvard.edu Department of Chemistry and Chemical Biology Harvard University Cambridge MA 02138 (USA) Fax: Int. code +(617)495-1460 e-mail: evans@chemistry.harvard.edu
New application for a chiral auxilary: N-acyl imides like 1, which is formed in an enantioselective aldol reaction, can be converted into thioesters and decarboxylated to give 2 (TES = Et3Si). The oxazolidinone auxili... 详细信息
来源: Wiley期刊 Wiley期刊 评论
An approach to the synthesis of the manzamine alkaloids via the vinylogous amide photocycloaddition retro-Mannich fragmentation Mannich closure cascade (pharM)
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Israel journal of Chemistry 1997年 第1期37卷 47-67页
作者: Winkler, JD Stelmach, JE Siegel, MG Haddad, N Axten, J Dailey, WP Department of Chemistry 231 South 34th Street The University of Pennsylvania Philadelphia Pennsylvania 19104 USA Department of Chemistry 231 South 34th Street The University of Pennsylvania Philadelphia Pennsylvania 19104 USA Department of Chemistry 231 South 34th Street The University of Pennsylvania Philadelphia Pennsylvania 19104 USA Department of Chemistry 231 South 34th Street The University of Pennsylvania Philadelphia Pennsylvania 19104 USA Department of Chemistry 231 South 34th Street The University of Pennsylvania Philadelphia Pennsylvania 19104 USA Department of Chemistry 231 South 34th Street The University of Pennsylvania Philadelphia Pennsylvania 19104 USA
The application of the vinylogous amide [2+2] photocycloaddition/retro-Mannich fragmentation/Mannich closure cascade (pharM) to the synthesis of the pentacyclic ring system of the anti-leukemic marine alkaloid manzami... 详细信息
来源: Wiley期刊 Wiley期刊 评论
A new synthesis of 4-phosphorylchromenes from 3-nitrochromenes
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Journal of heterocyclic Chemistry 1997年 第4期34卷 1243-1246页
作者: Ono, N Banshou, N Ito, S Murashima, T Ogawa, T Department of Chemistry Faculty of Science Ehime University Matsuyama 790 Japan Department of Chemistry Faculty of Science Ehime University Matsuyama 790 Japan Department of Chemistry Faculty of Science Ehime University Matsuyama 790 Japan Department of Chemistry Faculty of Science Ehime University Matsuyama 790 Japan Department of Chemistry Faculty of Science Ehime University Matsuyama 790 Japan
3-Nitrochromenes are readily converted into 4-phosphorylchromenes on treatment with dialkyl phosphite in the presence of triethylamine in 60-70% yield. This method provides a general method for the preparation of alke... 详细信息
来源: Wiley期刊 Wiley期刊 评论
Unusual regioselectivity in the reductive coupling of alkynes and allenes by hydrozirconation and zinca-Claisen rearrangement
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Angew. Chem. Int. Ed. Engl. 1997年 第22期36卷 2469-2471页
作者: Suzuki, K Imai, T Yamanoi, S Chino, M Matsumoto, T Department of Chemistry Tokyo Institute of Technology 2-12-1 O-okayama Meguro-ku Tokyo 152 (Japan) Department of Chemistry Keio University 3-14-1 Hiyoshi Kohoku-ku Yokohama 223 (Japan) Department of Chemistry Keio University 3-14-1 Hiyoshi Kohoku-ku Yokohama 223 (Japan) Department of Chemistry Keio University 3-14-1 Hiyoshi Kohoku-ku Yokohama 223 (Japan) Department of Chemistry Tokyo Institute of Technology 2-12-1 O-okayama Meguro-ku Tokyo 152 (Japan)
The α-adduct is the sole product of the coupling of vinyl- and allylzirconium compounds with ZnCl2 (see below), provided no MgII salts are present. The zirconium compounds are formed in situ from alkynes and allenes,... 详细信息
来源: Wiley期刊 Wiley期刊 评论
C-2-SYMMETRIC CATIONIC COPPER(II) COMPLEXES AS CHIRAL LEWIS-ACIDS - COUNTERION EFFECTS IN THE ENANTIOSELECTIVE DIELS-ALDER REACTION
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Angew. Chem. Int. Ed. Engl. 1995年 第7期34卷 798-800页
作者: EVANS, DA MURRY, JA VONMATT, P NORCROSS, RD MILLER, SJ Department of Chemistry Harvard University Cambridge MA 02138 (USA) Telefax: Int. code + (617)495-1460 Department of Chemistry Harvard University Cambridge MA 02138 (USA) Telefax: Int. code + (617)495-1460 Department of Chemistry Harvard University Cambridge MA 02138 (USA) Telefax: Int. code + (617)495-1460 Department of Chemistry Harvard University Cambridge MA 02138 (USA) Telefax: Int. code + (617)495-1460 Department of Chemistry Harvard University Cambridge MA 02138 (USA) Telefax: Int. code + (617)495-1460
Alone a tailor-made chiral cationic Lewis acid is not sufficient to achieve high enantiomic excesses in Diels–Alder reactions; the counterion can dramatically affect the efficiency of the chiral catalyst. Thus, for e... 详细信息
来源: Wiley期刊 Wiley期刊 评论
RING-OPENING REACTION OF THE PYRIDINIUM SALT OF 4-NITRO-3-ISOXAZOLIN-5-ONE - A PREPARATION OF TRIFUNCTIONALIZED METHANE DERIVATIVES
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Journal of heterocyclic Chemistry 1995年 第2期32卷 473-475页
作者: NISHIWAKI, N TAKADA, Y INOUE, Y TOHDA, Y ARIGA, M Department of Chemistry Osaka Kyoiku University Asahigaoka 4–698–1 Kashiwara Osaka 582 Japan Department of Chemistry Osaka Kyoiku University Asahigaoka 4–698–1 Kashiwara Osaka 582 Japan Department of Chemistry Osaka Kyoiku University Asahigaoka 4–698–1 Kashiwara Osaka 582 Japan Department of Chemistry Osaka Kyoiku University Asahigaoka 4–698–1 Kashiwara Osaka 582 Japan Department of Chemistry Osaka Kyoiku University Asahigaoka 4–698–1 Kashiwara Osaka 582 Japan
The ring cleavage of the pyridinium salt of 4-nitro-3-isoxazolin-5-one 1 was found to proceed under mild basic conditions and to give cyano-aci-nitroacetates 2 in quantitative yields. The ring opened products 2 have t...
来源: Wiley期刊 Wiley期刊 评论
A TOTAL SYNTHESIS OF (+)2'S,3'R-ZOAPATANOL
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Angew. Chem. Int. Ed. Engl. 1994年 第21期33卷 2182-2184页
作者: TROST, BM GREENSPAN, PD GEISSLER, H KIM, JH GREEVES, N Department of Chemistry Stanford University Stanford CA 94305-5080 (USA) Telefax: Int. code + (415)725-0259 Department of Chemistry Stanford University Stanford CA 94305-5080 (USA) Telefax: Int. code + (415)725-0259 Department of Chemistry Stanford University Stanford CA 94305-5080 (USA) Telefax: Int. code + (415)725-0259 Department of Chemistry Stanford University Stanford CA 94305-5080 (USA) Telefax: Int. code + (415)725-0259 Department of Chemistry Stanford University Stanford CA 94305-5080 (USA) Telefax: Int. code + (415)725-0259
Three palladium-catalyzed steps (allyl alkylation, Wacker oxidation, and carbonylative cross-coupling) characterize the first asymmetric total synthesis of 1, a component of plant extracts used as contraceptives.
来源: Wiley期刊 Wiley期刊 评论
BIS(PENTAFLUOROPHENYL)BORANE - SYNTHESIS, PROPERTIES, AND HYDROBORATION Chemistry OF A HIGHLY ELECTROPHILIC BORANE REAGENT
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Angew. Chem. Int. Ed. Engl. 1995年 第7期34卷 809-811页
作者: PARKS, DJ SPENCE, REVH PIERS, WE Guelph-Waterloo Centre for Graduate Work in Chemistry Guelph Campus Department of Chemistry and Biochemistry University of Guelph Guelph Ontario N1G 2W1 (Canada) Telefax: Int. code + (519)766-1499 Guelph-Waterloo Centre for Graduate Work in Chemistry Guelph Campus Department of Chemistry and Biochemistry University of Guelph Guelph Ontario N1G 2W1 (Canada) Telefax: Int. code + (519)766-1499 Guelph-Waterloo Centre for Graduate Work in Chemistry Guelph Campus Department of Chemistry and Biochemistry University of Guelph Guelph Ontario N1G 2W1 (Canada) Telefax: Int. code + (519)766-1499
A facile route provides the title compound 1 in only a few steps starting from bromopentafluorobenzene. Borane 1 is a very reactive hydroborating agent for a range of alkenes and alkynes. Reactions with unsymmetrical ... 详细信息
来源: Wiley期刊 Wiley期刊 评论
Synthesis of metal oxide composite nanosheets and their pressure sensing properties
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Journal of Semiconductors 2015年 第2期36卷
作者: Chani, Muhammad Tariq Saeed Khan, Sher Bahadar Karimov, Kh. S. Abid, M. Asiri, Abdullah M. Akhtar, Kalsoom King Abdulaziz University Jeddah Saudi Arabia Chemistry Department Faculty of Science King Abdulaziz University Jeddah Saudi Arabia Interdisciplinary Research Center COMSATS Institute of Information Technology Wah Cantt Pakistan Physical Technical Institute of Academy of Sciences Dushanbe Tajikistan Division of Nano Sciences Department of Chemistry Ewha Womans University Seoul Korea Republic of
This study presents the synthesis of metal oxides composite nanosheets (oxides of cobalt, zinc and iron) and their pressure sensing properties. A transducer has been fabricated to directly measure the resistance - pre... 详细信息
来源: IOP期刊 评论
Synthesis and aggregation of cationic porphyrins
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Journal of heterocyclic Chemistry 1997年 第3期34卷 749-755页
作者: Dancil, KPS Hilario, LF Khoury, RG Mai, KU Nguyen, CK Weddle, KS Shachter, AM Department of Chemistry Santa Clara University Santa Clara CA 95053 Department of Chemistry Santa Clara University Santa Clara CA 95053 Department of Chemistry Santa Clara University Santa Clara CA 95053 Department of Chemistry Santa Clara University Santa Clara CA 95053 Department of Chemistry Santa Clara University Santa Clara CA 95053 Department of Chemistry Santa Clara University Santa Clara CA 95053 Department of Chemistry Santa Clara University Santa Clara CA 95053
Tetra(N-R-pyridinium-4-yl)porphyrin and tetra(N-R-pyridinium-3-yl)porphyrin derivatives were synthesized with R = 3, 6, and 8 carbon alkene, alcohol and carboxylic acid chains. Self-aggregation of these systems was st... 详细信息
来源: Wiley期刊 Wiley期刊 评论