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• 88-05-1 2,4,6-trimethylaniline 
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• 910567-26-9 methyl (Z)-2-acetamido-3-(2',4',6'-trimethylphenyl)-2-propenoate 

Relevant academic research and scientific papers

MaxPHOS ligand: PH/NH tautomerism and rhodium-catalyzed asymmetric hydrogenations

MaxPHOS is an active and robust P-stereogenic ligand for asymmetric catalysis. The presence of an -NH- bridge between the two phosphine moieties allows the NH/PH tautomerism to take place. The neutral ligand, in which the NH form predominates, is an air-sensitive compound. However, protonation of MaxPHOS leads to the stable PH form of the ligand, in which the overall positive charge is distributed on both P centers. This protonation turns the MaxPHOS×HBF4 salt 3 into an air-stable compound both in the solid state and in solution. The salt 3 is also a convenient precursor for the preparation of rhodium(I) complexes by direct ligand exchange with the complex [Rh(acac)(cod)]. Finally, the corresponding rhodium(I)-MaxPHOS complex was tested in the asymmetric hydrogenation of a wide range of substrates. The complex proved to be a highly selective and robust system in these reactions.

Enantioselective synthesis of a phenylalanine library containing alkyl groups on the aromatic moiety: Confirmation of stereostructure by X-ray analysis

Six phenylalanine analogues containing 2′-methyl-, 2′,6′-dimethyl-, 2′-ethyl-6′-methyl-, 2′-isopropyl-6′-methyl-, 2′,4′,6′-trimethyl-, and 3′,5′-dimethyl-L-phenylalanine were synthesized enantioselectively through asymmetric hydrogenation of acetamidoacrylate derivatives. Enzymatic digestion and X-ray analysis supported the L-configuration of the phenylalanine derivatives obtained.