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Rational Design of Simple Organocatalysts for the HSiCl₃ Enantioselective Reduction of (E)-N-(1-Phenylethylidene)aniline.

ABSTRACT: Prolinamides are well-known organocatalysts for the HSiCl₃ reduction of imines; however, custom design of catalysts is based on trial-and-error experiments. In this work, we have used a combination of computational calculations and experimental work, including kinetic analyses, to properly understand this process and to design optimized catalysts for the benchmark (E)-N-(1-phenylethylidene)aniline. The best results have been obtained with the amide derived from 4-methoxyaniline and the N-pivaloyl protected proline, for which the catalyzed process is almost 600 times faster than the uncatalyzed one. Mechanistic studies reveal that the formation of the component supramolecular complex catalyst-HSiCl₃-substrate, involving hydrogen bonding breaking and costly conformational changes in the prolinamide, is an important step in the overall process.

SUBMITTER: Macia M

PROVIDER: S-EPMC8625272 | biostudies-literature |

REPOSITORIES: biostudies-literature

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