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Four acetyl cobalt complexes, [AcCo(CO)(3)P(p-tolyl)(3)] (1; p-tolyl=4-Me-C(6)H(4)), [AcCo(CO)(3)P(OPh)(3)] (2), [AcCo(CO)(3)P(NMe(2))(3)] (3), and [AcCo(CO)(2)(dppp)] (4; dppp=1,3-bis(diphenylphosphanyl)propane), were synthesized, characterized, and examined as catalysts for the unprecedented carbonylative polymerization of oxetanes. Copolymers containing ester (4-hydroxyalkanoate) and/or ether units were obtained with complexes 1 and 2, but not with complexes 3 and 4 either in the presence or absence of additional phosphorus ligands. The ester unit/ether unit ratio varied in the range 21:79-63:37, and the highest ester/ether ratio of 63:37 was achieved by using complex 1 in the presence of a further 5 equivalents of P(OPh)(3). Although direct carbonylative polymerization is possible, preformation and ring opening of the gamma-lactone is also suggested as an alternative pathway.

A CuO-CuAl2O4 nanocomposite (CuAl NC) synthesized by high temperature calcination of Cu-Al layered double hydroxides (CuAl LDHs) acted as an effective heterogeneous catalyst for acceptorless dehydrogenation of various alcohols. The catalytically active Cu0 species was formed by in situ reduction with alcohol. The catalytic activity strongly depended on the Cu/Al ratio in preparation and calcination temperature. The synthesized catalyst was reusable without loss of its high activity and selectivity.

Highly reducible CuO species were created by the calcination of a Cu-Al layered double hydroxide (CuAl LDH) at 1073 K under air. After this heat treatment, the original layered double hydroxide structure was completely transformed into CuO and CuAl2O4 phases. The synthesized calcined CuAl LDH (calc-CuAl LDH) promoted the catalytic hydrogenation of furfural (FALD) into furfuryl alcohol (FOL) with formic acid (FA) as a hydrogen donor. In the initial stage of the above catalytic reaction, the CuO species in the calc-CuAl LDH matrix transformed into active Cu0 species via the formation of a Cu(HCOO)2-1,4-dioxane complex in the liquid phase. The spent catalyst was also reusable without loss of its high catalytic performance.

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