ISSN:
0009-2940
Keywords:
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Derivatives of 1,4-Diborabenzene: The First Ionic 1,4-Diboratabenzene Compound and Transition Metal Complexes of 1,4-Dibora-2,5-cyclohexadienesThe 1,4-dibora-2,5-cyclohexadiene FcB[CH=CH]2BFc (1h) (FcH = Fe(C5H5)2) is reduced by sodium amalgam to produce diamagnetic Na2[FcB[C2H2]2BFc] containing a novel 6π-electron anion. 17 transition metal complexes (4-8) of Co, Rh, Ni, and Pt with 1,4-dibora-2,5-cyclohexadiene ligands L (L = RB[C2H2]2BR) are described. Complexes with R = Fc and CH3O are obtained by complexation of 1h, its dianion, or CH3OB[CH=CH]2BOCH3 (1c), respectively. Other substituents at boron including R = H, CH3, C6H5, Cl, and (CH3)2N may be introduced by nucleophilic substitution. In all cases the 1,4-dibora-2,5-cyclohexadiene ligands are η6-bonded. Attempted Friedel-Crafts acetylation of (C5R5)M{CH3B[C2H2]2BCH3} (M = Co, R = H and M = Rh, R = CH3) (5f, 6f) effects ring-member substitution to give the corresponding cationic borabenzene derivatives [(C5R5)M(4-CH3C5H4BCH3)]+ (e.g. 10+).
Notes:
Das 1,4-Dibora-2,5-cyclohexadien FcB[CH=CH]2BFc (1h) (FcH = Fe(C5H5)2) wird durch Natriumamalgam zu diamagnetischem Na2[FcB[C2H2]2BFc] reduziert, welches ein neuartiges 6π-Elektronen-Anion enthält. 17 übergangsmetall-Komplexe (4-8) von Co, Rh, Ni und Pt mit 1,4-Dibora-2,5-cyclohexadien-Liganden L (L = RB[C2H2]2BR) werden beschrieben. Komplexe mit R = Fc und CH3O werden durch Komplexierung von 1h, seinem Dianion oder von CH3OB[CH=CH]2BOCH3 (1c) erhalten. Andere Substituenten am Bor wie R = H, CH3, C6H5, Cl und (CH3)2N lassen sich durch nucleophile Substitution einführen. Die 1,4-Dibora-2,5-cyclohexadien-Liganden sind in allen Fällen η6-gebunden. Der Versuch der Friedel-Crafts-Acetylierung von (C5R5)M{CH3B[C2H2]2BCH3} (M = Co, R = H und M = Rh, R = CH3) (5f, 6f) bewirkt Ringgliedsubstitution und ergibt die entsprechenden kationischen Borabenzol-Derivate [(C5R5)M(4-CH3C5H4BCH3)]+ (z. B. 10+).
Additional Material:
2 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19821150917
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