- Synthetic process of metsulfuron-methyl-D3
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The invention provides a synthesis process of metsulfuron-methyl-D3, comprising the following steps: Step 1), adding a compound I in an ethanol solution of sodium ethoxide to prepare a compound II; Step 2), adding the compound II prepared in the Step 1) into a tetrahydrofuran solution of deuterated sodium methoxide, and refluxing to obtain a compound III; Step 3), suspending a compound IV in anhydrous toluene, dropwise adding a compound V, adding triethylene diamine, and heating to prepare a toluene solution of a compound VI; and Step 4), suspending the compound III prepared in the Step 2) in ethyl acetate in under nitrogen protection, heating and dropwise adding the toluene solution of the compound VI that is obtained in the Step 3), and reacting to prepare the final product metsulfuron-methyl-D3. The invention has the following technical effects: by conversion of the functional group of a relatively-cheap compound I, the compound III is synthesized; although the yield is low, cumbersome multi-step synthesis and the use of a large amount of expensive deuterated methanol are avoided.
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Paragraph 0042-0044
(2019/10/07)
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- Preparation of 2-amino-4-alkoxy-s-triazines
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2-Amino-4-alkoxy-s-triazines which are substituted by an alkyl, aryl or aralkyl moiety in the 6-position and which are useful as pharmaceutical agents and as intermediates for herbicides, dyes and optical brighteners are prepared by reacting a dialkyl (N-cyanoimido)carbonate with an amidine salt in the presence of an inert solvent and a base.
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- Process for the preparation of 2-amino-s-triazines
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The present invention relates to a process for the preparation of 2-amino-s-triazines in three stages. In the first stage nitriles, alcohols and hydrogen chloride are reacted to form the corresponding imido-ester hydrochlorides. In the second stage, the imido-ester hydrochlorides are reacted with cyanamide in the aqueous phase to form the N-cyanimido-esters, which comprises carrying out the first stage in the presence of acetic acid esters and the second stage in an aqueous solution which has been brought to a pH value of 5-8 by addition of bases, and reacting the N-cyanimido-esters with O-alkylisourea, S-alkylisothiourea, guanidine or amidine salts in the presence of a base in the third stage. The 2-amino-s-triazines can be prepared in a high purity and with good yields in this manner.
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