4984-22-9Relevant articles and documents
Preparation method of metolachlor
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Paragraph 0066-0068, (2020/03/17)
The method comprises the following steps, reacting methanol and: propylene oxide to obtain (R)- methoxy - 2 2-ethyl aniline (R)- 1 - reacting the compound with, methyl - 6 6-ethylaniline to obtain I methyl - 222222227, by reacting I methyl-6-ethylaniline. 2 - The compound S - (-) - N - (R - shown) - 2 - is prepared by reacting the compound shown, with a sulfuryl chloride compound in a short, reaction step in a process, of reacting, with a chloroacetyl chloride compound in a short time of (S)- in a short time, The present, invention provides, a, method for producing metotilachlor in the. following steps: STR2715 STR7#
Optimized Synthetic Route for Enantioselective Preparation of (S)-Metolachlor from Commercially Available (R)-Propylene Oxide
Yang, Peng,Wang, Xiao,Peng, Lin,Chen, Feng,Tian, Fang,Tang, Chao-Zhe,Wang, Li-Xin
, p. 1682 - 1688 (2017/10/25)
An enantioselective preparation of (S)-metolachlor has been accomplished. The synthetic route featured the asymmetric preparation of chiral intermediates and the final (S)-metolachlor from commercially available (R)-propylene oxide and a key Fukuyama's process. The key steps, control points, separation purifications, and the whole process are optimized, and the target compound has been successfully prepared in five steps in 51-55% overall yield with excellent enantioselectivity (99% ee) up to a 30 g scale. By judicious choice of synthetic route and selection of starting materials and intermediates, no column chromatographic methods are needed for the separation and purification of the intermediates and the final products. The same strategy was extended as a general method for a series of pesticides and herbicide analogs of Metalaxyl-M and Dimethenamid-P.
Ketone-alcohol hydrogen-transfer equilibria: Is the biooxidation of halohydrins blocked?
Bisogno, Fabricio R.,Garcia-Urdiales, Eduardo,Valdes, Haydee,Lavandera, Ivan,Kroutil, Wolfgang,Suarez, Dimas,Gotor, Vicente
supporting information; experimental part, p. 11012 - 11019 (2010/11/18)
To ensure the quasi-irreversibility of the oxidation of alcohols coupled with the reduction of ketones in a hydrogen-transfer (HT) fashion, stoichiometric amounts of a-halo carbonyl compounds have been employed as hydrogen acceptors. The reason that these substrates lead to quasi-quantitative conversions has been tacitly attributed to both thermodynamic and kinetic effects. To provide a clear rationale for this behavior, we investigate herein the redox equilibrium of a selected series of ketones and 2-propanol by undertaking a study that combines experimental and theoretical approaches. First, the activity of the (R)-specific alcohol dehydrogenase from Lactobacillus brevis (LBADH) with these substrates was studied. The docking of acetophenone/(R)-l-phenyethanol and a-chloroacetophenone/(S)-2-chloro- lphenylethanol in the active site of the enzyme confirms that there seems to be no structural reason for the lack of reactivity of halohydrins. This assumption is confirmed by the fact that the corresponding aluminum-catalyzed Meerwein-Ponndorf-Verley-Oppenauer (MPVO) reactions afford similar conversions to those obtained with LBADH, showing that the observed reactivity is independent of the catalyst employed. While the initial rates of the enzymatic reductions and the IR v(C=0) values contradict the general belief that electron-withdrawing groups increase the electrophilicity of the carbonyl group, the calculated βG values of the isodesmic redox transformations of these series of ketones/alcohols with 2-propanol/acetone support the thermodynamic control of the reaction. As a result, a general method to predict the degree of conversion obtained in the HT-reduction process of a given ketone based on the IR absorption band of the carbonyl group is proposed, and a strategy to achieve the HT oxidation of halohydrins is also shown.
