- Mixed metal bases as promoters of 1,4-eliminations
-
When treated with the LIDAKOR mixture, allyl type ethers very readily undergo 1,4-elimination to afford conjugated dienes (3 - 73). In typical cases, the reaction is brought about stereo- and regioselectively (2 and 7, respectively). Under suitable conditions, lithium dimethylamide or even lithium diisopropylamide adds to the dienes generated in situ thus leading to a variety of new allyl amines (5-8).
- Margot, Christian,Matsuda, Hiroyuki,Schlosser, Manfred
-
p. 2425 - 2430
(2007/10/02)
-
- Une synthese hautement stereoselective de dienes conjugues (E)
-
A general method for the preparation of (E) terminal conjugated dienes was developed by the flash thermolysis of 2-substituted 2,5-dihydrothiophene-1,1-dioxides generated by a retro Diels-Alder reaction.This process allows the obtention of conjugated dienes, bearing or not a functionality (alcohols, esters), with an excellent stereoisomeric purity (in general higher than 98percent).An application to the synthesis of (E)-9,11-dodecadien-1-yl acetate, the major component of the sex pheromone of Diparopsis castanea, shows the generality and the efficacy of this method.
- Bloch, R.,Abecassis, J.,Hassan, D.
-
p. 2019 - 2024
(2007/10/02)
-
- A HIGHLY STEREOSELECTIVE SYNTHESIS OF (E)-1- SUBSTITUTED-1,3-DIENES.
-
(E)-1-substituted-1,3-dienes are obtained with high selectivity by the thermal extrusion of SO2 from 2-substituted-2,5-dihidrothiophene-1,1-dioxides generated by a retro Diels-Alder reaction.An application to the synthesis of (E)-9,11-dodecadien-1-yl acetate, a sex pheromone of the red-bollworm moth is described.
- Bloch, R.,Abecassis, J.
-
p. 3277 - 3280
(2007/10/02)
-