The first carbene-C,N chelate tetracarbonyl dihalogeno and carbene-C,O chelate tetracarbonyl benzochinone tungsten complexes
| Autor: | Bernhard Weibert, Helmut Fischer, Rüdiger Stumpf, Nicolai Burzlaff |
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| Rok vydání: | 2002 |
| Předmět: |
Chemistry
Organic Chemistry Decarbonylation chemistry.chemical_element Tungsten Photochemistry Iodine Chelate complexes Biochemistry Medicinal chemistry Oxidative decarbonylation Single isomer Tungsten complexes Inorganic Chemistry chemistry.chemical_compound Carbene complexes ddc:540 Materials Chemistry Chelation Physical and Theoretical Chemistry Carbene |
| Zdroj: | Journal of Organometallic Chemistry. 651:66-71 |
| ISSN: | 0022-328X |
| Popis: | The carbene-C,N chelate tetracarbonyl tungsten complex [(CO) 4 / W C(Ph)NHC 5 H 4 N -o](4), obtained from [(CO) 5 WC(Ph)OMe] (3) and o-aminopyridine, reacts with iodine by oxidative decarbonylation to give a single isomer of the carbene-C,Nchelate tricarbonyl dihalogeno tungsten(II) complex [(CO) 3 I 2 / W C(Ph)NHC 5 H 4 N -o](5). The analogous reaction of 4 with bromineaffords two interconverting isomers of [(CO) 3 Br 2 / W C(Ph)NHC 5 H 4 N -o](6). The oxidative decarbonylation of the carbene-C,Ochelate tetracarbonyl tungsten complex [(CO) 4 / W C(OMe)C 6 H 4 O Me-o](1) with tetrachloro-o-benzochinone yields the firstcarbene-C,O chelate tricarbonyl-o-benzochinone tungsten(II) complex 8. The structures of 5 and of [(CO) 4 I 2 / W C(OMe)C 6 H 4 OMe-o](2c) were established by X-ray structural analyses. # 2002 Elsevier Science B.V. All rights reserved. Keywords: Carbene complexes; Oxidative decarbonylation; Chelate complexes; Tungsten complexes 1. IntroductionThere are only few examples known of Fischer-typemolybdenum(II) and tungsten(II) carbene carbonylcomplexes not stabilized by aromatic p-ligands [1].In1977, Lappert and Pye reported the synthesis of someLappert-type W(II) complexes with cyclic bisaminocar-bene ligands [2] by oxidation of the corresponding W(0)carbene complexes. However, compared to Fischer-typecarbene ligands, the back-bonding properties of the N-heterocyclic carbene ligands is almost negligible [3].Inaddition, a few compounds of the type [Cl |
| Databáze: | OpenAIRE |
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