ISSN:
0009-2940
Keywords:
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Synthesis and Reactivity of 2-Borolenes and of 3-BorolenesC-Unsubstituted 3-borolenes C4H6BR (1) with alkyl, aryl, or dialkylamino substituents at boron are obtained by treating RBX2 (MeBBr2, C6H11BCl2, PhBCl2, o-TolBCl2, MesBCl2, Me2NBCl2, Et2NBCl2, (iPr)2NBCl2) with Mg(C4H6) · 2 THF in ether. Catalytic isomerization reactions produce the corresponding 2-borolenes C4H6BR (2) (R = Ph, NMe2, NEt2, N(iPr)2). Additional 2-borolenes (R = Me, Ph, Cl, OMe) can be obtained efficiently via 1-(diisopropylamino)-2-borolene (2h). Addition of organolithium reagents (LiMe, LiPh) and subsequent treatment with HCl in Et2O affords 1-R-2-borolenes (R = Me, Ph). Addition of polar reagents HX (HCl, MeOH) and subsequently of HCl in Et2O produces 1-heterosubstituted 2-borolenes (R = Cl, OMe). All borolenes are highly air- and watersensitive liquids of high reactivity. In addition to the usual characterization a number of simple crystalline derivatives, including some boratacyclopentene salts, are also described.
Notes:
C-Unsubstituierte 3-Borolene C4H6BR (1) mit Alkyl-, Aryl- oder Dialkylamino-Substituenten am Bor werden durch Umsetzung von RBX2 (MeBBr2, C6H11BCl2, PhBCl2, o-TolBCl2, MesBCl2, Me2NBCl2, Et2NBCl2, (iPr)2NBCl2) mit Mg(C4H6) · 2 THF in Ether erhalten. Katalytische Isomerisierungsreaktionen liefern die entsprechenden 2-Borolene C4H6BR (2) (R = Ph, NMe2, NEt2, N(iPr)2). Weitere 2-Borolene (R = Me, Ph, Cl, OMe) können günstig mit Hilfe von 1-(Diisopropylamino)-2-borolen (2h) erhalten werden. Addition von lithiumorganischen Agenzien (LiMe, LiPh) und anschließende Behandlung mit HCl in Et2O liefert 1-R-2-borolene (R = Me, Ph). Addition von polaren Agenzien HX (HCl, MeOH) und danach von HCl in Et2O ergibt 1-heterosubstituierte 2-Borolene (R = Cl, OMe). Alle Borolene sind sehr luft- und wasserempfindliche Flüssigkeiten von hoher Reaktivität. Zusätzlich zur üblichen Charakterisierung werden einige einfache kristallisierte Derivate beschrieben, darunter einige Boratacyclopenten-Salze.
Additional Material:
4 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19861190205
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