51575-86-1Relevant articles and documents
Preparation method of chiral ligand(3S, 4S)-2, 5-dioxotetrahydrofuran-3, 4-bis(benzyl carbamate)
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Paragraph 0042-0044, (2020/06/17)
The invention relates to the field of chiral transition metal catalysts, and relates to a preparation method of a chiral ligand(3S, 4S)-2, 5-dioxotetrahydrofuran-3, 4-bis(benzyl carbamate). The methodcomprises the following steps: taking internal compensation 1, 3-dibromosuccinic acid as a raw material; carrying out esterification reaction under the catalysis of acid to generate diester (I); carrying out nucleophilic substitution reaction on the compound (I) and amine to obtain a compound (II); carrying out a removal reaction on the compound (II) under the action of trifluoroacetic acid to obtain amino diester (III); carrying out acylation reaction on the compound (III) and acyl chloride to obtain amide (IV); and hydrolyzing the ester group of the compound (IV) into acid (V) under an alkaline condition, and finally performing intramolecular dehydration on the compound (V) to obtain the chiral transition metal catalyst intermediate. The invention provides a simple and convenient industrial production route for the chiral transition metal catalyst intermediate, the reaction operation is simple, the use of an expensive palladium reagent is avoided, and the cost is lower.
Thiophene Analogues of the Alkaloids. Part 6. Synthesis of Thiophene Analogues of Some 1-Benzylisoquinolines.
Huddleston, Patrick R.,Barker, John M.,Stickland, Barbara,Wood, Michael L.,Guindi, Laila H. M.
, p. 1871 - 1890 (2007/10/02)
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