Method for preparing (4R-cis)-6-substituted-2,2-dimethyl-1,3-dioxane-4-tert-butyl acetate

A technology of tert-butyl acetate and 4r-cis, which is applied in the field of pharmaceuticals, can solve problems such as difficult control of the operation process and unsatisfactory de values ​​of compounds, and achieve the effects of increasing yield and reducing costs
CN102180862BActive Publication Date: 2013-08-28VALIANT CO LTD
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Patents(China)
Current Assignee / Owner
VALIANT CO LTD
Publication Date
2013-08-28

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Abstract

The invention relates to a method for preparing (4R-cis)-6-substituted-2,2-dimethyl-1,3-dioxane-4-tert-butyl acetate with a structural formula (VIII) shown in the specifications. In the formula, R is formaldehyde or methanol. In the preparation method, Blaise reaction is used for replacing complicated Claisen ester condensation reaction with a large number of side reactions, the aim of growing a carbon chain is fulfilled under the mild condition, and expensive lithium diisopropylamide (LDA) and a low-temperature environment is avoided; and a complicated route of oxidizing alcohol into aldehyde is avoided in the process of generating the compound VIII.
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Description

technical field

[0001] The invention relates to a preparation method of (4R-cis)-6-substituted-2,2-dimethyl-1,3-dioxane-4-acetic acid tert-butyl ester, which belongs to the field of pharmacy. Background technique

[0002] (4R-cis)-6-substituted-2,2-dimethyl-1,3-dioxane-4-tert-butyl acetate is an important intermediate in the synthesis of the hypolipidemic drug Rosuvastatin . There are many reports about the synthetic route of this compound at present.

[0003] G.Wess et al. (Wess, G.et al.Tetrahedron Lett.1990, 31, 2545) reported a kind of (S)-3,4-dihydroxybutyric acid methyl ester as a starting material, through the following steps Generate the target compound.

[0004]

[0005] The route yield is low, deprotection is difficult, and the de value (diastereoisomeric excess) is not high. And need to use expensive lithium diisopropylamide (LDA) as the catalyst of condensation reaction, the high cost is not suitable for industrial production.

[0006] U.S. Patent No. 5,3...

Claims

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