We present an inverse-design method, the poor man's materials optimization, that is designed to identify materials within a very large class with optimized values for a pre-chosen property. The method combines an efficient genetic-algorithm-based optimization, an automatic approach for generating modified molecules, a simple approach for calculating the property of interest, and a mathematical formulation of the quantity whose value shall be optimized. In order to illustrate the performance of our approach, we study the properties of organic molecules related to those used in dye-sensitized solar cells, whereby we, for the sake of proof of principle, consider benzene as a simple test system. Using a genetic algorithm, the substituents attached to the organic backbone are varied and the best performing molecules are identified. We consider several properties to describe the performance of organic molecules, including the HOMO-LUMO gap, the sunlight absorption, the spatial distance of the orbitals, and the reorganisation energy. The results show that our method is able to identify a large number of good candidate structures within a short time. In some cases, chemical/physical intuition can be used to rationalize the substitution pattern of the best structures, although this is not always possible. The present investigations provide a solid foundation for dealing with more complex and technically relevant systems such as porphyrins. Furthermore, our "properties first, materials second" approach is not limited to solar-energy harvesting but can be applied to many other fields, as briefly is discussed in the paper.

Chiral α-amino ketones are excellent nucleophiles for stereoselective palladium-catalyzed allylic alkylations. Both chiral as well as achiral allylic substrates can be applied, while the stereochemical outcome of the reaction is controlled by the chiral ketone enolate. The substituted amino ketones formed can be reduced stereoselectively, and up to five consecutive stereogenic centers can be obtained. This approach can be used for the synthesis of highly substituted piperidine derivatives.

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Chirale a-Aminoketone sind hervorragende Nukleophile für hochs tereoselektive Palladium-katalysierte ally-lischeA lkylierungen, sowohlm it chiralen als aucha chiralen Allylsubstraten, wobei die Steuerung über das chirale Ketonenolat überwiegt. Die erhaltenen substituierten Aminoketone lassen sich anschließend stereoselektiv reduzieren, wobei bis zu fünf benachbarte Stereozentren erhalten werden kçnnen. Dies ermçglicht auchd en Aufbau eines hochs ubstituierten Piperidinderivates. Schema 1. Stereoselektive Synthese a-quartärer Ketone durch decarboxylierende allylische Alkylierung.Schema 2. Stereoselektive Peptidmodifizierung durch allylische Alkylierung. ds:D iastereoselektivität.Schema 3. Potenziellec helatisierteE nolate N-geschützter a-Aminoketone. SG:Schutzgruppe.