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Stereocontrolled synthesis of α,β-unsaturated carboxylic esters from O-methyl-C,O-bis(trimethylsilyl)ketene acetal and aliphatic aldehydes

✍ Scribed by Isamu Matsuda; Yusuke lzumi

Publisher
Elsevier Science
Year
1981
Tongue
French
Weight
241 KB
Volume
22
Category
Article
ISSN
0040-4039

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✦ Synopsis

R*,S*) Selective aldol type reaction of O-methyl-C,O-bis(trimethylsilyl)ketene acetal (,j.) with aldehydes and stereoselective formation of c,B-unsaturated carboxylic esters are attained by the combination of 2-A and Lewis acids. One of the most versatile methods to E selective synthesis of a,$-unsaturated carboxylic esters is the Wadsworth-Wittig-Horner type reaction 1 which is controlled thermodynamically. Alkyl trimethylsilylacetate carbanion is also used as a highly reactive condensation reagent with carbonyl compounds. 2, 3 But the stereocontrol of the reactions is almost impossible.

📜 SIMILAR VOLUMES

Stereoselective synthesis of (E)- α, β -
Stereoselective synthesis of (E)- α, β -unsaturated acids from C,O,O-tri (trimethylsilyl) ketene acetal and aldehydes.
✍ Moncef Bellassoued; Marcel Gaudemar 📂 Article 📅 1988 🏛 Elsevier Science 🌐 French ⚖ 169 KB

Aldehydes are converted into (E)-CI , fi -unsaturated carboxylic acids by means of C,O,O -tri(trimethylsilyl) ketene acetal and a catalytic amount of ZnBr2. Several ways have been described to transform aldehydes into c1 , 6 -unsaturated esters. However, the hydrolysis of the resultant esters to t