Regio- and diastereoselective synthesis of 2-alkylidenetetrahydrofurans by domino SN/SN' and SN/SN reactions of 1,3-dicarbonyl dianions.
The domino C,O-cyclodialkylation reaction of dilithiated 1,3-dicarbonyl compounds with 1,4-dibromo-2-butene resulted in regio- and diastereoselective formation of 2-alkylidene-5-vinyltetrahydrofurans. The cyclization of 1,3-dicarbonyl dianions with 1-bromo-2-chloroethane regio- and diastereoselectively afforded 2-alkylidenetetrahydrofurans under thermodynamic reaction control.
Langer
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P
Institut für Organische Chemie, Georg-August-Universität, Göttingen, Tammannstrasse 2, 37077 Göttingen, Germany. planger@uni-goettingen.de
Holtz
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E
Karimé
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I
Saleh
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