In the crystals of phthalic acid trans-cinnamamide (1:2), two molecules of cinnamamide are connected with phthalic acid via a hydrogen bond to form a three-component assembly. The C=C double bonds of two cinnamamides take a criss-crossed arrangement with a center-to-center distance of 4.252(3) A and with a twist angle of 97.1(4) degrees. After a partial single-crystal-to-single-crystal transformation, X-ray analysis revealed the beta-type photodimer of cinnamamide in the assembly at 13.2(3)% conversion. This suggests that the pedal-like conformational change occurred for one of the cinnamamide molecules and the C=C bond of the other cinnamamide moved approximately parallel to form a cyclobutane ring.

Both enantiomers of Wieland-Miescher ketone [3,4,8, 8a-tetrahydro-8a-methyl-1,6(2H,7H)-naphthalenedione], in a highly enantiomerically enriched form, became readily available by a newly developed kinetic resolution with yeast-mediated reduction. From a screening of yeast strains, Torulaspora delbrueckii IFO 10921 was selected. The collected cells of this strain, obtained by an incubation in a glucose medium, smoothly reduced only the isolated carbonyl group of the (S)-enantiomer, while the (R)-enantiomer remained intact. Starting from both enantiomers ( approximately 70% ee) prepared by an established proline-mediated asymmetric Robinson annulation, the reduction with T. delbrueckii gave the (R)-enantiomer (98% ee) and the corresponding alcohol (4aS,5S)-4,4a, 5,6,7,8-hexahydro-5-hydroxy-4a-methyl-2(3H)-naphthalenone (94% ee, 94% de) in preparative scale in nearly quantitative yields. An approach for the asymmetric synthesis of the Wieland-Miescher ketone was also successful. 2-Methyl-2-(3-oxobutyl)-1,3-cyclohexanedione, the prochiral precursor, was reduced with this strain to give a cyclic acetal form of (2S, 3S)-3-hydroxy-2-methyl-2-(3-oxobutyl)cyclohexanone, in a stereomerically pure form.

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Crystal structures of 2,4,6-triisopropylbenzophenone (I) and its ten derivatives have been determined: (II) 2,4,6-triisopropyl-3′-methoxybenzophenone, (III) 3′-chloroformyl-2,4,6-triisopropylbenzophenone, (IV) methyl 3-(2,4,6-triisopropylbenzoyl)benzoate, (V) 2,4,6-triisopropyl-4′-methylbenzophenone, (VI) 4′-tert-butyl-2,4,6-triisopropylbenzophenone, (VII) 2,4,6-triisopropyl-4′-methoxybenzophenone, (VIII) 4-(2,4,6-triisopropylbenzoyl)benzoic acid, (IX) 4′-chloroformyl-2,4,6-triisopropylbenzophenone, (X) methyl 4-(2,4,6-triisopropylbenzoyl)benzoate and (XI) ethyl 4-(2,4,6-triisopropylbenzoyl)benzoate. The conformations of these molecules are essentially the same. The central carbonyl moiety is approximately coplanar with the 3′- or 4′-substituted phenyl group and perpendicular to the triisopropylphenyl ring. The photostability of (IX) and (X) in the solid state is attributed to the narrow reaction cavity of the triisopropylphenylcarbonyl moiety, i.e. the intramolecular movements of isopropyl groups in the triisopropylphenyl plane toward the carbonyl C atom are suppressed by intermolecular close contacts. One of the barriers for the photocyclization of (IX) and (X) is caused by a dimeric structure in crystals through the π–π interaction, which is the result of having a polar methoxycarbonyl or chloroformyl group at position 4′ of the phenyl ring.