ISSN:
0009-2940
Keywords:
Stereoselectivity
;
Diels-Alder reaction
;
β1-Lactone
;
α1-methylene-
;
Spirolactones
;
Alkylidene cycloalkenes
;
Decarboxylation
;
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Notes:
A number of spiro-β1-lactones was prepared in good to excellent yields through stereoselective [4 + 2] cycloaddition of β1-isopropyl-α1-methylene-β1-lactone (1) with acyclic, cyclic, heterocyclic and aromatic 1,3-dienes by sealed-tube reaction at moderate temperatures (50 - 130°C). Flash pyrolysis of the resulting spiro-β1-lactones 2 in the gas phase at 400°C afforded by decarboxylation exclusively the corresponding (E)1-isopropylidenealkenes in high yields with retention of the initial geometry and without double bond isomerization. This olefination method constitutes an excellent stereoselective synthesis of (E)1-alkylidenecycloalkenes.
Additional Material:
1 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19931260632
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