Thermal and structural characterization of a series of homoleptic Cu(II) dialkyldithiocarbamate complexes: bigger is only marginally better for potential MOCVD performance

A series of Cu(II) dialkyldithiocarbamate complexes, Cu(S2CNRR')(2), with R = R' = n-Bu (1); i-Bu (2); c-Hex (3); CH2Ph (4); R = n-Bu, R' = Et (5); R = n-Pr, R' = c-PrCH2 (6); R = R' = n-Pr (7); i-Pr (8); allyl (9), were prepared. The thermal properties of the complexes were investigated to determine if their potential performance in chemical vapor deposition processes was affected by the nature of the peripheral substituents of the ancillary ligands. Modest gains in volatility were noted for 2 and 7 over the most often utilized complex with R = R' = Et, while I and 8 had thermal parameters and stability comparable to this standard. Unsymmetrical substitution, such as in 5, also improved volatility, with some loss of stability for this particular compound. X-ray diffraction studies of complexes 1-6 suggested that long range Cu...S interactions in the solid-state have little bearing on the thermal properties of this class of Cu(II) complexes. (C) 2003 Elsevier Science Ltd. All rights reserved.