Darwinian evolution and chemistry

Competition versus Cooperation in Catalytic Hydrogelators for anti-Selective Mannich Reaction

Chemical systems find similarities in different sociological and biological processes, in which the entities compete or cooperate for a favorable outcome. The structural and functional adaptations leading to emergent properties, especially in catalysis, are based on factors such as abundance of substrates, stability of the transition state, and structural/functional attributes of catalysts. Proline and acid groups appended to catalytic fibers of two self-sorting hydrogelators compete for the Mannich reaction between aniline, benzaldehyde, and cyclohexanone to give low overall selectivity (anti/syn 77:23). In a sol-gel system of the same molecules, on the other hand, the soluble acid appended molecules tend to cooperate with the fibers of proline-appended catalyst to give improved selectivity (anti/syn 95:5). The available options for the catalytic molecules are to carry out the reaction independently or in cooperation. However, these options are chosen based on the efficiency, selectivity, and mobility of catalysts as a result of their abilities to self-assemble.

Metal ions as external stimuli in stereoselective self-sorting of koneramines and thiokoneramines

Stereoselective self-sorting of koneramines and thiokoneramines, which are N3 ligands, evolved from the system of pyridine-2-carboxaldehyde, mono-N-substituted ethylenediamine, primary alcohol or thiol, is observed when metal ions such as Ni(ii), Cu(ii), Zn(ii) and Cd(ii) are added as external stimuli to isolate the emergent molecule.