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1.
Morpholine amides are cheap and safe alternative to Weinreb amides as acylating agents of organometallic species. Herein, the in-situ lithiation/borylation of 18 ortho- meta- and para-substituted morpholine benzamides has been investigated. 10 of the 18 substrates provided the desired boronic esters as the major isomer (>90% regioselectivity) in crude isolated yields ranging from 68 to 93%. The synthetic usability of such building blocks was subsequently illustrated via the synthesis of a kinase inhibitor. 相似文献
2.
The synthesis of substituted 2-cyanoarylboronic esters is described via lithiation/in situ trapping of the corresponding methoxy-, trifluoromethyl-, fluoro-, chloro-, and bromobenzonitriles. The crude arylboronic esters were obtained in high yields and purities and with good regioselectivities. 相似文献
3.
The paper deals with finite–difference (f-d) approach to simulation of elastic waves' propagation in anisotropic elastic media with general symmetry. Any implementation of this approach claims resolution of two key problems:
- construction of an effective f-d scheme itself; we propose to use the Lebedev's scheme (LS) being a natural generalization of Virieux staggered grid scheme (VS) widely used for isotropy; we prove that LS possesses better dispersion properties in comparison with well known Rotated Staggered Grids Scheme (RSGS).
- stable domain distension. The Perfectly Matched Layers(PML) useful for isotropic problems can be unstable in the case of anisotropy. Lebedev scheme allows one to use Optimal Grids (OG) which gives a possibility to implement efficient and low cost domain distension.
4.
Aihara H Alston-Garnjost M Avery RE Barker AR Bauer DA Bay A Belcinski R Bingham HH Bloom ED Buchanan CD Caldwell DO Chao HY Chun SB Clark AR Cowan GD Crane DA Dahl OI Daoudi M Derby KA Eastman JJ Eberhard PH Edberg TK Eisner AM Erné FC Fairfield KH Fridman A Godfrey G Hauptman JM Ho C Hofmann W Kamae T Kenney RW Khacheryan S Kofler RR Lambert DJ Langeveld WG Layter JG Lin WT Linde FL Loken SC Lu A Lynch GR Lys JE Madaras RJ Magnuson BD Marsiske H Masek GE Mathis LG Maxfield SJ Miller ES 《Physical review D: Particles and fields》1991,43(1):29-33
5.
Aderholz M Aggarwal MM Akbari H Allport PP Badyal SK Ballagh HC Barth M Baton JP Bingham HH Brucker EB Burnstein RA Campbell JR Cence RJ Chatterjee TK Clayton EF Corrigan G Coutures C DeProspo D Devanand De Wolf EA Faulkner PJ Foeth H Fretter WB Gupta VK Hanlon J Harigel G Harris FA Jabiol MA Jacques P Jain V Jones GT Jones MD Kafka T Kalelkar M Kasper P Kohli JM Koller EL Krawiec RJ Lauko M Lys JE Marage P Milburn RH Miller DB Mittra IS Mobayyen MM Moreels J Morrison DR Myatt G Nailor P 《Physical review D: Particles and fields》1992,45(7):2232-2243
6.
High-performance liquid chromatography-time-of-flight mass spectrometry and its application to peptide analyses 总被引:1,自引:0,他引:1
R C Simpson W B Emary I Lys R J Cotter C C Fenselau 《Journal of chromatography. A》1991,536(1-2):143-153
High-performance liquid chromatography (HPLC) has been successfully interfaced on-line with liquid secondary-ion time-of-flight mass spectrometry, utilizing a continuous-flow interface. Time-of-flight mass spectrometry (TOF-MS) is a low-resolution, high-mass-range technique, compatible with extremely rapid data acquisition rates. Thus a TOF-MS system is extremely well suited for coupling with HPLC. This paper describes the interface used to couple the HPLC and TOF-MS as well as the basic operating principles of such a system. Using both standard and packed-capillary reversed-phase HPLC columns, the HPLC-TOF-MS system has been successfully used to separate and detect peptides, providing molecular weight information for the peptide analytes. Experimental data, including chromatograms (UV, reconstructed ion and selected ion) and mass spectra, are presented to demonstrate the ability of the HPLC-liquid secondary-ion TOF-MS system to resolve chromatographically analytes as well as to resolve mass spectrometrically analytes which are unresolved on the chromatographic column. 相似文献
7.
Willocq S Aderholz M Akbari H Allport PP Badyal SK Ballagh HC Barth M Bingham HH Brucker EB Burnstein RA Cence RJ Chatterjee TK Clayton EF Corrigan G De Prospo D Devanand De Wolf E Faulkner PJ Foeth H Fretter WB Gupta VK Hanlon J Harigel G Harris FA Jacques P Jain V Jones GT Jones MD Kafka T Kalelkar M Kohli JM Koller EL Krawiec RJ Lauko M Lys JE Marage P Milburn RH Mittra IS Mobayyen MM Moreels J Morrison DR Myatt G Nailor P Naon R Napier A Passmore D Peters MW Peterson VZ Plano R Rao NK 《Physical review D: Particles and fields》1993,47(7):2661-2674
8.
Patricia S. C. Pereira L. C. Mendes M. L. Dias Lys Sirelli 《Journal of Thermal Analysis and Calorimetry》2007,87(3):667-671
The effects of processing time
and concentration of cobalt acetylacetonate III complex in poly(ethylene terephthalate)/polycarbonate
reactive blending were investigated. The blend was prepared in an internal
mixer at 270°C, 60 rpm, at different processing times (5–20 min)
and catalyst concentration (0.00625–0.075 mass%). The reaction product
was evaluated by differential scanning calorimetry (DSC), thermogravimetry
(TG) and wide angle X-rays scattering (WAXS).
In general, the
DSC curves showed two glass transition temperatures (T
g’s)
close to each homopolymer, independent of the processing time and complex’s
concentration, suggesting the presence of two phases: one rich in PET and
other one rich in PC. In all cases, melting temperature (T
m),
cold crystallization temperature (T
cc)
and crystallinity degree (X
c)
were progressively reduced with blending conditions. The TG curves presented
two decays. The first one represented the PET rich phase and the other one
was related to the PC phase. The WAXS diffractograms showed that the Bragg’s
angle and interplanar spacing of PET remaining practically unchanged. 相似文献
9.
Ganushchak N. I. Romanyuk A. L. Litvin B. L. Lys R. I. Polishchuk O. P. 《Russian Journal of General Chemistry》2001,71(2):286-289
2,3-Bis(benzotriazol-1-yl)-1,4-naphthoquinone reacts with aliphatic and aromatic amines to give the corresponding 2-amino-3-(benzotriazol-1yl)-1,4-naphthoquinones, and its reaction with alkali gives 2-hydroxy-3-(benzotriazol-1-yl)-1,4-naphthoquinone. 相似文献
10.
Ortho-substituted arylboronic esters are efficiently coupled with carbamoyl chlorides under Pd-catalysis to give tertiary benzamides. 相似文献