Diastereomeric diphosphites (L∩L ) 3-8) have been synthesized from enantiomerically pure pentane-2,4-diol and axially chiral 3,3′-bis(trialkylsilyl)-2,2′-bisphenol phosphorochloridites and 3,3′-bis(trialkylsilyl)-2,2′-bisnaphthol phosphorochloridites. These diphosphites have been used to test the influence of chiral cooperativity in the rhodium-catalyzed asymmetric hydroformylation of styrene. Systematic variation in chirality at both the chiral ligand bridge and the axially chiral biphenyl and binaphthyl substituents revealed a remarkable effect on the selectivity of the hydroformylation catalysts. For the atropisomeric bisnaphthol-based diphosphites, cooperative effects were observed in the asymmetric hydroformylation of styrene. High enantioselectivities (87%) and regioselectivities up to 95% for 2-phenylpropanal were found under mild reaction conditions (15-50°C, 20 bar of syn gas CO-H 2 [1:1]) for the ligand derived from (2R,4R)-pentane-2,4-diol and (S)-bisnaphthol. The same high enantiomeric excess was observed for the free-rotating bisphenol-substituted ligands. The highest selectivity was obtained with trimethylsilyl substituents at the ortho position. The solution structures of the active catalysts [HRhL∩L-(CO) 2 complexes (L∩L ) 3-8)], have been studied by 31 P and 1 H NMR spectroscopy at variable temperature (313-213 K). Spectroscopic data, in combination with the obtained results in catalysis, suggest that diphosphite ligands (L∩L) containing the conformationally flexible axially chiral biphenyl moieties predominantly exist as single atropisomers in the HRhL∩L-(CO) 2 complexes. Comparison of the bisphenol and bisnaphthol substituents suggests that the high enantiomeric excesses obtained with the former are caused by the preferential formation of the most selective diastereomer.

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An innovative BASF catalyst manufacturing technology (NanoSelect TM ) is introduced which allows production of heterogeneous catalysts with excellent control over metal crystallite sizes. NanoSelect TM technology enabled the development of Pd catalysts which are leadfree Lindlar catalyst replacements in alkyne-to-cis-alkene hydrogenations. NanoSelect TM Pt catalysts showed excellent chemoselectivity in substituted nitro-arene hydrogenation reactions without build-up of hydroxylamine intermediates. All NanoSelect TM produced catalysts show markedly higher activity per gram of metal leading to tenfold less use of precious metal.

A series of cationic palladium complexes of general formula [Pd(Me)(MeCN)(N-N)][PF(6)] (N-N = (phen) 1 a, 4,7-dichloro-1,10-phenanthroline (4,7-Cl(2)-phen) 2 a, 4,7-diphenyl-1,10-phenanthroline (4,7-Ph(2)-phen) 3 a, 4-methyl-1,10-phenanthroline (4-Me-phen) 4 a, 4,7-dimethyl-1,10-phenanthroline (4,7-Me(2)-phen) 5 a, 5,5,6,6-tetrafluoro-5,6-dihydro-1,10-phenanthroline (F(4)-phen) 6 a, containing different substituted phenanthroline ligands, have been prepared from the corresponding neutral chloro derivatives [Pd(Me)(Cl)(N-N)], (1 b-6 b). The X-ray crystal structure of [Pd(Cl)(2)(4,7-Cl(2)-phen)] (2 b') was determined. DFT calculations show that the electron density on the metal is tuned by the substituents on the ligands. The catalytic behavior of complexes 1 a-6 a in the CO/styrene and CO/p-Me-styrene copolymerizations was studied in detail, showing that the generated catalysts are active for at least 90 h, yielding copolymers of high molecular weight. A firm correlation between the electron density on palladium on the one hand and the catalytic activity of the complexes and the molecular weight and the stereochemistry of the polyketones synthesized on the other hand has been established: the catalyst containing the F(4)-phen is thus far the most active among those tested, yielding the syndiotactic CO/styrene copolymer with a stereoregularity of 96 % (uu triad) and with an M(w) value of 1 000 000.

A series of donor‐functionalized pyrylium salts have been prepared by classical condensation reactions which were further converted into the corresponding thienyl‐ and pyridyl‐substituted polydentate λ3‐phosphinines by reaction with P(SiMe3)3. Further chemical modification of these phosphorus heterocycles with Hg(OAc)2 in the presence of methanol resulted in the formation of λ5‐phosphinines. The photophysical properties of a selected series of thienyl‐ and pyridyl‐functionalized pyrylium salts, λ3‐ and λ5‐phosphinines, were investigated and the results compared and supported by theoretical calculations on the DFT level. Significant fluorescence was observed for the pyrylium salts and λ5‐phosphinines. In contrast, the heteroaromatic substituted λ3‐phosphinines show very little emission which is consistent with the low oscillator strength predicted by DFT calculations for this π→π* transition. Furthermore, all three classes of compounds show readily observable phosphorescence in solution, which was determined by time‐gated detection at low temperature.