We have synthesized, crystallized and studied the structural and electric transport properties of organic molecular crystals based on a rubrene derivative with t-butyl sidegroups at the 5,11 positions. Two crystalline modifications are observed: one (A) distinct from that of rubrene with larger spacings between the naphtacene backbones, the other (B) with a in-plane structure presumably very similar compared to rubrene. The electric transport properties reflect the different structures: in the latter phase (B) the in-plane hole mobility of 12 cm 2 /Vs measured on single crystal FETs is just as high as in rubrene crystals, while in the A phase no field-effect could be measured. The high crystal quality, studied in detail for B, reflects itself in the density of gap states: The deep-level trap density as low as 10 15 cm −3 eV −1 has been measured, and an exponential band tail with a characteristic energy of 22 meV is observed. The bulk mobility perpendicular to the molecular planes is estimated to be of order of 10 −3 -10 −1 cm 2 /Vs.

The useful combination of high catalytic activity and high enantioselectivity is provided by rhodium catalysts based on a new class of FerroTANE ligands when employed in the hydrogenation of itaconate derivatives (see scheme). Reactions performed at S/C ratio of 20 000 are complete within 3 h and directly afford valuable 2‐alkylsuccinamide products in up to 99 % enantiomeric excess.

A simple access to a new class of Cz-symmetric auxiliaries and ligands is based on the transacetalization of diethyl tartrate (1) with monoacetals of butane-2,3-dione in the key step. Acidcatalyzed reaction of 1 with 2 equiv of 3,3-diethoxybutan-2-one (2) gives the Cz-symmetric 1,4dioxane 7 in 88% yield. Reduction of 7 with LiAlH4 affords the crystalline diol 9. The structure of 7 was established from the X-ray structure of 9. Dioxane 7 was converted by standard methodology into the diphosphine 24 and the TARTROL 22. Reaction of 1 with 3,3-dimethoxybutan-2-one (3) in the presence of BFs-etherate gives in analogy to the formation of 7 the 1,4-dioxane 8. This compound was transformed into the diphosphine 25 and the TARTROL 23. The trans-diaxial relationship of the methoxy groups present in 8 could be deduced without X-ray analysis from the lH-NMR spectrum of 23.

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