- Chromium(II)-Catalyzed Diastereoselective and Chemoselective Csp2-Csp3 Cross-Couplings Using Organomagnesium Reagents
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A simple protocol for performing chromium-catalyzed highly diastereoselective alkylations of arylmagnesium halides with cyclohexyl iodides at ambient temperature has been developed. Furthermore, this ligand-free CrCl2 enables efficient electrophilic alkenylations of primary, secondary, and tetiary alkylmagnesium halides with readily available alkenyl acetates. Moreover, this chemoselective C-C coupling reaction with stereodefined alkenyl acetates proceeds in a stereoretentive fashion. A wide range of functional groups on alkyl iodides and alkenyl acetates are well tolerated, thus furnishing functionalized Csp2-Csp3 coupling products in good yields and high diastereoselectivity. Detailed mechanistic studies suggest that the in situ generated low-valent chromium(I) species might be the active catalyst for these Csp2-Csp3 cross-couplings.
- Li, Jie,Ren, Qianyi,Cheng, Xinyi,Karaghiosoff, Konstantin,Knochel, Paul
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supporting information
p. 18127 - 18135
(2019/11/19)
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- SYNTHESIS METHOD FOR L-CYCLIC ALKYL AMINO ACID AND PHARMACEUTICAL COMPOSITION HAVING THEREOF
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A synthesis method for L-cyclic alkyl amino acid and a pharmaceutical composition having the said amino acid are provide in the present disclosure provides. The synthesis method comprises: step A.) preparing a cyclic alkyl keto acid or a cyclic alkyl keto acid salt having Structural Formula (I) or Structural Formula (II), and step B.) mixing the cyclic alkyl keto acid or the cyclic alkyl keto acid salt with ammonium formate, a leucine dehydrogenase, a formate dehydrogenase and a coenzyme NAD+, and carrying out a reductive amination reaction to generate the L-cyclic alkyl amino acid, wherein the Structural Formula (I) is where n1≧1, m1≧0 and the M1 is H or a monovalent cation; the Structural Formula (II) is where n2≧0, m2≧0, the M2 is H or a monovalent cation, an amino acid sequence of the leucine dehydrogenase is SEQ ID No.1.
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Paragraph 0061-0062
(2016/11/17)
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- SPIRO AZETIDINE ISOXAZOLE DERIVATIVES AND THEIR USE AS SSTR5 ANTAGONISTS
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Provided is a compound represented by the following formula (1) or a salt thereof, which has an SSTR5 antagonistic action: wherein each symbol has the same definition as in the specification.
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Paragraph 1257
(2014/09/29)
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- Dibenzyl Amine Compounds and Derivatives
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Dibenzyl amine compounds and derivatives, pharmaceutical compositions containing such compounds and the use of such compounds to elevate certain plasma lipid levels, including high density lipoprotein-cholesterol and to lower certain other plasma lipid levels, such as LDL-cholesterol and triglycerides and accordingly to treat diseases which are exacerbated by low levels of HDL cholesterol and/or high levels of LDL-cholesterol and triglycerides, such as atherosclerosis and cardiovascular diseases in some mammals, including humans.
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Page/Page column 79; 80
(2010/11/28)
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- Thermochemical Bond Dissociation Energies of Carbon-Magnesium Bonds
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The heats of formation of 29 alkylmagnesium bromides, isobutyl bromide, and neopentyl bromide have been determined, and bond dissociation energies have been derived for the Grignard reagents.For saturated alkyl derivatives the C-Mg bond strength decreases with an increasing number of β-hydrogens in the series methyl, neopentyl, isobutyl, butyl, ethyl, 1-ethylpropyl, 1-methylpropyl, isopropyl, and t-butyl.Bonding in alkyl bromides and alkylmagnesium bromides is discussed.
- Holm, Torkil
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p. 464 - 467
(2007/10/02)
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