The direct chemo-enzymatic DKR of racemic beta-haloalcohols is reported, yielding the corresponding optically active epoxides in a single step. The mutant haloalcohol dehalogenase HheC Cys153Ser Trp249Phe is used for the asymmetric ring closure, whereas racemization of the remaining enantiomer of the haloalcohol is achieved using the new iridacycle 3, one of the most effective racemization catalysts to date for beta-haloalcohols.

The sterically hindered bis(phenol)-dipyrrin ligands LH and LH were reacted with 1 equiv of copper(II) under ambient conditions to produce the copper radical complexes [Cu(L)] and [Cu(L)]. Their X-ray crystal structures show relatively short C-O bond distances (mean bond distances of 1.287 and 1.291 Å), reminiscent of mixed pyrrolyl-phenoxyl radical species. Complexes [Cu(L)] and [Cu(L)] exhibit rich electronic spectra, with an intense near-IR (NIR) band (ε > 6 mM cm) at 1346 and 1321 nm, respectively, assigned to a ligand-to-ligand charger-transfer transition. Both show a reversible oxidation wave ( E = 0.05 and 0.04 V), as well as a reversible reduction wave ( E = -0.40 and -0.56 V versus ferrocenium/ferrocene, respectively). The cations ([Cu(L)] and [Cu(L)]) and anions ([Cu(L)] and [Cu(L)]) were generated. They all display an axial ( S = /) signal with a copper hyperfine structure in their electron paramagnetic resonance spectra, consistent with ligand-centered redox processes in both reduction and oxidation. Complex [Cu(L)](SbF) was cocrystallized with [Cu(L)]. Oxidation is accompanied by a slight contraction of both the C-O bonds (mean bond distance of 1.280 Å) and the C-C bonds connecting the peripheral rings to the dipyrrin. The cations show vis-NIR bands of up to 1090 nm due to their quinoidal nature. The anions do not show a significant band above 700 nm, in agreement with their bis(phenolate)-dipyrrin character. The radical complexes efficiently catalyze the aerobic oxidation of benzyl alcohol, 1-phenylethanol, and unactivated 2-phenylethanol in basic conditions.

The cis,cis,cis-1,2,3,4-tetrakis(diphenylphosphinomethyl)-cyclopentane-[PdCl(eta3-C3H5)]2 system catalyses the coupling of aryl halides with alkynes with very high ratios of substrates-catalyst in good yields; a turnover number of 2600000 can be obtained for the reaction of 4-trifluoromethylbromobenzene with phenylacetylene in the presence of this catalyst.

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The lipase‐catalysed resolution of alcohols and amines yields only 50 % of the desired enantiopure product. However, addition of a racemisation catalyst leads to 100 % yield in what is called a dynamic kinetic resolution (DKR). There is a need for new racemisation catalysts that are fast and compatible with the conditions of the enzymatic reaction. We show that cationic half‐sandwich ruthena‐ and iridacycle complexes are highly active and efficient in the racemisation of chiral alcohols and amines. Upon activation with base, these complexes are able to selectively racemise alcohols, whereas the non‐activated complexes are selective catalysts for the racemisation of amines. We have applied the iridacycles in the DKR of racemic β‐chloroalcohols to produce chiral epoxides in a biphasic system in good yields and high ee (ee=enantiomeric excess).

A range of aryl bromides undergo a Heck vinylation reaction with a protected allyl alcohol in the presence of [PdCl(C 3 H 5 )] 2 /cis,cis,cis-1,2,3,4-tetrakis(diphenylphosphanylmethyl)cyclopentane as a catalyst. The reactivity of these allyl alcohol derivatives using a variety of protecting groups has been studied. The best results in terms of substrate/catalyst ratio were obtained with a THP protecting group. In most cases, the major isomer obtained was the (E)-cinnamyl

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The multistep catalytic process using designer cells, either added as freshly prepared suspensions or as stable lyophilized powder, and click reaction can be performed in one pot. The sequence of four reactions allows the production of both enantiomers of b-hydroxytriazoles with high enantiomeric excess.