TY - JOUR
T1 - Synthesis and reactions of tungsten(II) norbornadiene (nbd) complexes. The crystal and molecular structure of [WBr(SC6F5)(CO)2(nbd)]
AU - Carlton, Laurence
AU - Davidson, Jack L.
AU - Vasapollo, Giuseppe
AU - Douglas, Graeme
AU - Muir, Kenneth W.
PY - 1993
Y1 - 1993
N2 - The reaction of [WBr2(CO)2(nbd)] 1 (nbd = norbornadiene) with Tl(C5H5) gave a monocarbonyl derivative [WBr(CO)(nbd)(?5-C5H5)] 2. With Tl(O2CMe) and Tl[O(S)CMe], complex 1 gave monosubstituted derivatives [WBr(O2CMe)(CO)2(nbd)] 3a and [WBr{O(S)CMe}(CO)2(nbd)] 3b which appear to be seven-co-ordinate according to IR data. In contrast 1 and Tl(SC6F5) (1:1 molar ratio) gave the six-co-ordinate complex [WBr(SC6F5)(CO)2(nbd)] 4. An X-ray diffraction study of 4 established that it has a distorted-octahedral structure with trans W-CO bonds approximately perpendicular to a plane containing the W. Br and S atoms and the midpoints of the nbd C=C bonds. Simple electronic arguments provide a rationalisation of many of the structural features of 4. Reaction of 1 with 2 molar equivalents of Tl(SC6F5) gave the bis(thiolate) derivative [W(SC6F5)2(CO)2(nbd)] 5 again with a trans arrangement of CO ligands. The reactions of 5 with L = PEt3, PMe2Ph or P(OMe)3 gave the six-co-ordinate complexes [W(SC6F5)2(CO)2L2] 6 which exist in two isomeric forms, red or green. Dynamic NMR studies have been used to characterise the isomeric behaviour and fluxional processes in the complexes.
AB - The reaction of [WBr2(CO)2(nbd)] 1 (nbd = norbornadiene) with Tl(C5H5) gave a monocarbonyl derivative [WBr(CO)(nbd)(?5-C5H5)] 2. With Tl(O2CMe) and Tl[O(S)CMe], complex 1 gave monosubstituted derivatives [WBr(O2CMe)(CO)2(nbd)] 3a and [WBr{O(S)CMe}(CO)2(nbd)] 3b which appear to be seven-co-ordinate according to IR data. In contrast 1 and Tl(SC6F5) (1:1 molar ratio) gave the six-co-ordinate complex [WBr(SC6F5)(CO)2(nbd)] 4. An X-ray diffraction study of 4 established that it has a distorted-octahedral structure with trans W-CO bonds approximately perpendicular to a plane containing the W. Br and S atoms and the midpoints of the nbd C=C bonds. Simple electronic arguments provide a rationalisation of many of the structural features of 4. Reaction of 1 with 2 molar equivalents of Tl(SC6F5) gave the bis(thiolate) derivative [W(SC6F5)2(CO)2(nbd)] 5 again with a trans arrangement of CO ligands. The reactions of 5 with L = PEt3, PMe2Ph or P(OMe)3 gave the six-co-ordinate complexes [W(SC6F5)2(CO)2L2] 6 which exist in two isomeric forms, red or green. Dynamic NMR studies have been used to characterise the isomeric behaviour and fluxional processes in the complexes.
UR - http://www.scopus.com/inward/record.url?scp=37049079091&partnerID=8YFLogxK
U2 - 10.1039/DT9930003341
DO - 10.1039/DT9930003341
M3 - Article
SN - 1472-7773
SP - 3341
EP - 3347
JO - Journal of the Chemical Society, Dalton Transactions
JF - Journal of the Chemical Society, Dalton Transactions
IS - 22
ER -