- Method for resolving chiral compound
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The invention relates to the field of organic chemistry, in particular to a method for resolving a chiral compound. The method for splitting the chiral compound provided by the invention comprises thestep of carrying out addition reaction on a racemic compound shown as a formula A and azodicarbonic acid ester in the presence of a catalyst so as to provide an S-configuration compound shown as theformula A and an S-configuration compound shown as the formula C. According to the method, chiral phosphoric acid is used as a catalyst; good catalytic effect is achieved, and very wide substrate applicability is also achieved; the product and the recovered raw material can be obtained with excellent enantioselectivity, the selectivity coefficient of kinetic resolution can reach 371, and the method has an excellent kinetic resolution effect on various N-monosubstituted and N-unsubstituted binaphthalene diamines, H8-binaphthalene diamines and biphenyl diamines.
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Paragraph 0081; 0116-0118
(2020/08/27)
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- Photochemical nitration by tetranitromethane. Part XXVI. Adduct formation in the photochemical reaction of 1,2,3-trimethylbenzene: The formation of 'double' adducts including nitronic esters
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The photolysis of the charge-transfer complex of 1,2,3-trimethylbenzene and tetranitromethane gives a complex mixture of products, most of which arise by initial attack of trinitromethanide ion on the unsubstituted ring positions at C4(C6) and C5 of the radical cation of 1,2,3-trimethylbenzene. The products 7-19 are adducts resulting directly or indirectly from the addition of the elements of tetranitromethane to 1,2,3-trimethylbenzene, and the trinitromethyl aromatic compounds 22-25 are formed by eliminations from intermediate adducts. Six adducts are simple 'single' adducts, nitro-trinitromethyl adducts 7, 8, 10-12, while nitro cycloadduct 9 is formed by cycloaddition of nitro-trinitromethyl adduct 8. The remaining addition products are 'double' adducts, formed by secondary addition reactions initiated by attack of nitrogen dioxide on the buta-1,3-diene system of 'single' adducts, and include trinitro-trinitromethyl compounds 13 and 15, the hydroxy-dinitro-trinitromethyl compound 14, and a group of four nitronic esters 16-19 formed by nitro-denitrocyclization of initially formed hydroxy-trinitromethyl and nitro-trinitromethyl 'single' adducts. Minor amounts of other products are formed including two nitrodienones 21 and 22, and the rearrangement product, 4,5,6-trimethyl-2-nitrophenol (28), and the 2,3,4-trimethyl- and 3,4,5-trimethylnitrobenzenes 26 and 27. The modes of formation of the above products are discussed, and X-ray crystal structure determinations are reported for compounds 9, 13, 14, 18, 19, 22 and 29. Acta Chemica Scandinavica 1996.
- Butts, Craig P.,Eberson, Lennart,Hartshorn, Michael P.,Robinson, Ward T.,Timmerman-Vaughan, David J.,Young, Dawson A. W.
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- Aromatic Substitution. 48. Boron Trifluoride Catalyzed Nitration of Aromatics with Silver Nitrate in Acetonitrile Solution
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Benzene, alkylbenzenes, halobenzenes, and anisole were nitrated with silver nitrate/boron trifluoride in acetonitrile solution.Correlation of competitive rates with ?- and ?-complex stabilities indicated that the transition state of highest energy lies relatively early on the reaction coordinate.Data indicate that nitrations occur via a polarized complex of the nitrating agent, with the catalyst undergoing nucleophilic displacement by the aromatic substrate.
- Olah, George A.,Fung, Alexander P.,Narang, Subhash C.,Olah, Judith A.
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p. 3533 - 3537
(2007/10/02)
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