Phosphite copper(I) trifluoroacetates [((RO)3P)mCuO2CCF3] (m = 1, 2, 3): synthesis, solid state structures and their potential use as CVD precursors.

Metal-organics [((RO)(3)P)(m)CuO(2)CCF(3)] (R = CH(3): 11a, m = 1; 11b, m = 2; 11c, m = 3. R = CH(2)CH(3): 12a, m = 1; 12b, m = 2; 12c, m = 3. R = CH(2)CF(3): 13a, m = 1; 13b, m = 2; 13c, m = 3) are either accessible by the reaction of [((RO)(3)P)(m)CuCl] (R = CH(3): 5a, m = 1; 5b, m = 2; 5c, m = 3. R = CH(2)CH(3): 6a, m = 1; 6b, m = 2; 6c, m = 3) with [KO(2)CCF(3)] (7), or treatment of [Cu(2)O] (8) with HO(2)CCF(3) (9) and P(OR)(3) (2, R = CH(3); 3, R = CH(2)CH(3); 4, R = CH(2)CF(3)). (31)P{(1)H} NMR spectra [((CH(3)O)(3)P)(m)CuO(2)CCF(3)] (m = 1, 1.5, 2, 2.5, 3, 3.5, and 4) have been studied at 25 and -80 °C showing phosphite ligand exchange in solution. The molecular structures of 11a and 13a-13c in the solid state are reported. Complexes 11a and 13a are tetramers featuring μ-η(2)(1κO:2κO')- and μ(3)-η(2)(1κO:2κO':3κO')-(11a) or μ(3)-η(2)(1κO:2κO':3κO')-bonded O(2)CCF(3) ligands (13a) with the Cu(I) ions being part of CuPO(2) and CuPO(3) units (11a), while in 13a solely a CuPO(3) moiety is present. Skeletal isomerism of 11a vs. 13a is discussed. Compound 13b is dimeric ({CuP(2)O(2)}(2)) with pseudo-tetrahedral Cu environments and μ-η(2)(1κO:2κO')O(2)CCF(3) functionalities. In monomeric 13c the O(2)CCF(3) ligand is η(1)(κO)-bonded to a tetra-coordinated Cu(i) ion. The thermal solid state properties of 11, 12 and 13 were studied by Thermo Gravimetry (TG). These complexes decompose by phosphite elimination, decarboxylation and dealkylation. Hot-wall Chemical Vapour Deposition (CVD) experiments were carried out at 380 °C using 11c as precursor for the deposition of copper onto pieces of TiN-coated oxidized silicon substrates. Copper layers of high purity were obtained with grain sizes between 200-1200 nm.