The chemical shifts of C(2)-C(5) carbon atoms of the series of substituted-cyclopentadienyl Cp(M) derivatives - (CO) 2Co[η 5-(C 5H 4-sub)] (1-5), (C 4Ph 4)Co[η 5-(C 5H 4COOCH 3)] (6), (CO) 3(CH 3)W[η 5-(C 5H 4-sub)](7-9), (CO) 3(Cl)W[η 5-(C 5H 4COOCH 3)] (10), (CO) 2(NO) Cr[η 5-(C 5H 4-sub)] (11-23), and (NO) 2(Cl)Cr[η 5-(C 5H 4COOCH 3)] (24) - have been assigned using two-dimensional HETCOR NMR spectroscopy. The assigned chemical shifts were compared with the NMR data of their ferrocene analogs. We observed that H(3,4) resonate at a lower field than H(2,5) resonate in (CO) 2Co(η 5-C 5H 4CHO) 1. The structure of (CO) 3(CH 3) W[η 5-(C 5H 4COCH 3)] 8 has been determined by X-ray diffraction studies. The electron density distribution in the cyclopentadienyl ring is discussed on the basis of 13C NMR data and that of 10 and (CO) 2Co[η 5-(C 5H 4COONS)] (NS = N-succinimidyl) (25) is compared with calculations using the density functional B3LYP exchange-correlation method. ? 2012 Elsevier B.V. All rights reserved.
Relation:
Inorganica Chimica Acta Volume 394, 1 January 2013, Pages 337-347