- Mechanistic Studies on the Organocatalytic α-Chlorination of Aldehydes: The Role and Nature of Off-Cycle Intermediates
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Herein we report the isolation and characterization of aminal intermediates in the organocatalytic α-chlorination of aldehydes. These species are stable covalent ternary adducts of the substrate, the catalyst and the chlorinating reagent. NMR-assisted kinetic studies and isotopic labeling experiments with the isolated intermediate did not support its involvement in downstream stereoselective processes as proposed by Blackmond. By tuning the reactivity of the chlorinating reagent, we were able to suppress the accumulation of rate-limiting off-cycle intermediates. As a result, an efficient and highly enantioselective catalytic system with a broad functional group tolerance was developed.
- Ponath, Sebastian,Menger, Martina,Grothues, Lydia,Weber, Manuela,Lentz, Dieter,Strohmann, Carsten,Christmann, Mathias
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supporting information
p. 11683 - 11687
(2018/09/10)
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- Synthesis method of phthalimide and phenyl ring-substituted phthalimide derivative
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The invention provides a synthesis method of phthalimide and a phenyl ring-substituted phthalimide derivative. The synthesis method comprises that aromatic ketone and ammonia gas or an ammonia gas precursor as substrates and air or oxygen as an oxygen source undergo a reaction under catalyst action and liquid phase conditions to produce phthalimide and a phenyl ring-substituted phthalimide derivative. The synthesis method is mild, realizes high oxidation efficiency and a high product yield, utilizes oxygen or air as an oxygen source, is economic and eco-friendly and has a good application prospect.
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Paragraph 0013; 0017; 0018; 0020; 0023; 0028
(2017/08/25)
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- Direct access to cobaltacycles via C-H activation: N-chloroamide- enabled room-temperature synthesis of heterocycles
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Cobaltacycle synthesis via C-H activation has been achieved for the first time, providing key mechanistic insight into cobalt catalytic chemistry. NChloroamides are used as a directing synthon for cobalt-catalyzed roomtemperature C-H activation and construction of heterocycles. Alkynes as coupling partners allow convenient access to isoquinolones, a class of synthetically and pharmaceutically important compounds. The broad substrate scope enables a diverse range of substitution patterns to be incorporated into the heterocyclic scaffold.
- Yu, Xiaolong,Chen, Kehao,Guo, Shan,Shi, Pengfei,Song, Chao,Zhu, Jin
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supporting information
p. 5348 - 5351
(2017/11/07)
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- Grinding imidation of anhydrides on smectite clays as recyclable and heterogeneous catalysts under solvent-free conditions
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Imidation of various anhydrides employing solvent-free grindstone technique using smectite clays as recyclable and green catalysts was examined and obtained excellent yields.
- Marvi, Omid
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p. 3501 - 3504
(2017/08/14)
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- PYRAZOLOPYRIDINE PYRAZOLOPYRIMIDINE AND RELATED COMPOUNDS
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In one aspect this invention relates generally to compounds of Formula: and sub-formulas thereof, or a tautomer of each thereof, a pharmaceutically acceptable salt of each thereof, or a pharmaceutically acceptable solvate of each of the foregoing, where X1, L1, L3, and R3 are described herein.
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Paragraph 0870; 0871
(2015/11/25)
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- BENZIMIDAZOLE INHIBITORS OF LEUKOTRIENE PRODUCTION
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The present invention relates to compounds of formula (I) and pharmaceutically acceptable salt thereof, wherein R1-R7 are as defined herein. The invention also relates to pharmaceutical compositions comprising these compounds, method
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Page/Page column 145
(2011/06/25)
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- Inhibitors of dipeptidyl peptidase 8 and dipeptidyl peptidase 9. Part 2: Isoindoline containing inhibitors
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To obtain selective and potent inhibitors of dipeptidyl peptidases 8 and 9, we synthesized a series of substituted isoindolines as modified analogs of allo-Ile-isoindoline, the reference DPP8/9 inhibitor. The influence of phenyl substituents and different P2 residues on the inhibitors' affinity toward other DPPs and more specifically, their potential to discriminate between DPP8 and DPP9 will be discussed. Within this series compound 8j was shown to be a potent and selective inhibitor of DPP8/9 with low activity toward DPP II.
- Van Goethem, Sebastiaan,Van der Veken, Pieter,Dubois, Veronique,Soroka, Anna,Lambeir, Anne-Marie,Chen, Xin,Haemers, Achiel,Scharpe, Simon,De Meester, Ingrid,Augustyns, Koen
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scheme or table
p. 4159 - 4162
(2009/05/07)
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- Process improvements for the preparation of kilo quantities of a series of isoindoline compounds
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A series of isoindoline analogues with either an indazole (HMR 2934, HMR 2651) or benzisoxazole (HMR 2543) appendage were prepared for the proposed treatment of psychiatric disorders such as obsessive compulsive disorder and attention deficit disorder. The isoindoline compounds were prepared by reduction of the corresponding phthalimides with LiAlH4. One compound was not chiral, and the other two required an enantioselective synthesis. The key step for these optically active analogues involved the coupling by an SN2 process of either a piperazynyl intermediate or a piperdinyl intermediate with methyl 3-benzyloxy-2-trifluoromethansulfonatopropionate. The products for these two analogues had >98% ee. Process improvements led to the multi-kilogram syntheses of each of these compounds.
- Watson, Timothy J.,Ayers, Timothy A.,Shah, Nik,Wenstrup, David,Webster, Mark,Freund, David,Horgan, Stephen,Carey, James P.
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p. 521 - 532
(2013/09/05)
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