The first carbene-C,N chelate tetracarbonyl dihalogeno and carbene- C,O chelate tetracarbonyl benzochinone tungsten complexes
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چکیده
The carbene-C ,N chelate tetracarbonyl tungsten complex [(CO)4/ W C(Ph)NHC5H4N /-o ] (4), obtained from [(CO)5W / C(Ph)OMe] (3) and o -aminopyridine, reacts with iodine by oxidative decarbonylation to give a single isomer of the carbene-C ,N chelate tricarbonyl dihalogeno tungsten(II) complex [(CO)3I2/ W C(Ph)NHC5H4N /-o ] (5). The analogous reaction of 4 with bromine affords two interconverting isomers of [(CO)3Br2/ W C(Ph)NHC5H4N /-o ] (6). The oxidative decarbonylation of the carbene-C ,O chelate tetracarbonyl tungsten complex [(CO)4/ W C(OMe)C6H4O /Me-o ] (1) with tetrachloro-o -benzochinone yields the first carbene-C ,O chelate tricarbonyl-o -benzochinone tungsten(II) complex 8. The structures of 5 and of [(CO)4I2/ W C(OMe)C6H4O / Me-o ] (2c) were established by X-ray structural analyses. # 2002 Elsevier Science B.V. All rights reserved.
منابع مشابه
Crystal structure of tetracarbonyl(2,2'-dipyridylamine)tungsten.
Tetracarbonyl(2,2'-dipyridylamine)tungsten was prepared from W(CO)6 and 2,2'-dipyridylamine in toluene. The structure was determined by an X-ray diffraction analysis. Crystal data: triclinic; space group, P-1 (No.2); a = 8.454(1)A, b = 13.369(2)A, c = 6.9452(9) A, a= 85.88(1) degrees, beta = 68.28(1) degrees, gamma = 80.93(1) degrees, V= 720.0(1)AI; Z = 2.
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