ISSN:
0009-2940
Keywords:
Chemistry
;
Inorganic Chemistry
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Chemistry and Pharmacology
Description / Table of Contents:
Borabenzene Derivatives, XIII. Cationic Borinato-metal Complexes. Nucleophilic Addition and Ring Contraction ReactionsSyntheses of cationic borabenzene complexes [ML(C5H5B—C6H5)]+ with ML = Co(C5H5) (1+ ), Co(C5H5B—C6H5) (2 + ), Rh{C5(CH3)5} (3 + ), Ir{C5(CH3)5} (4 + ), and Ru(C6H6) (5 +) are described. These cations are much more electrophilic than the corresponding cyclopentadienyl complexes [ML(C5H5)] +. With nucleophiles three types of reactions are observed: i) nucleophilic addition at boron producing stable adducts, e.g. in the systems l +/C5H5N,3+/CN-. and 4 + /CN-. - ii) ring-contraction of borinato ligands in l +,2+, and 3+ forming cyclopentadienyl ligands. - iii) nucleophilic addition at carbon if the nucleophile is H- (from NaBH4) producing complexes ML(4-H—C5H5B-C6H5), ML(6-H—C5H5B—C6H5), and M(LH)(C5H5B—C6H5) from 1+, 2+, and 3+.
Notes:
Synthesen kationischer Borabenzol-Komplexe [ML(C5H5B—C6H5]+ mit ML = Co(C5H5) (1+), Co(C5H5B-C6H5)(2+), Rh{C5(CH3)5} (3 + ), Ir{C5(CH3)5}(4+) und Ru(C6H6)(5+) werden beschrieben. Diese Kationen sind sehr viel elektrophiler als die entsprechenden Cyclopentadienyl-Komplexe [ML(C5H5)] +. Mit Nucleophilen werden drei Arten von Reaktionen beobachtet: 1. nucleophile Addition am Bor unter Bildung stabiler Addukte, z. B. in den Systemen 1+/C5H5N, 3+/CN- und 4+/CN-. - 2. Ringkontraktionen von Borinat-Liganden in 1+, 2+ und 3+ unter Bildung von Cyclopentadienyl-Liganden. - 3. nucleophile Addition am Kohlenstoff, wenn das Nucleophil H- (aus NaBH4) ist, unter Bildung von Komplexen ML(4-H—C5H5B—C6H5), ML(6-H—C5H5B—C6H5) und M(LH)(C5H5B—C6H5) aus 1+ 2+ und 3 +.
Additional Material:
2 Tab.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/cber.19791120223
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