Chiral Aziridine Phosphines as Highly Effective Promoters of Asymmetric Rauhut–Currier Reaction

Abstract

A series of chiral enantiomerically pure aziridines containing a phosphine moiety were synthesized and successfully applied as organocatalysts in asymmetric intramolecular Rauhut–Currier reactions of p-quinone derivatives. The desired chiral phenols were achieved in high chemical yields and with satisfactory values of enantiomeric excess (up to 98% ee, in some cases). The stereochemical course of the title reaction may be controlled by the use of an appropriate enantiomer of the catalyst. The individual enantiomers of the organocatalyst led to the formation of specific enantiomers of the chiral product.

Phosphine-catalysed transformations of ortho- and para-quinone methides

“…In 2022, Rachwalski and coworkers reported an intramolecular Rauhut-Currier reaction catalysed by a chiral phos- phine/aziridine catalyst VI (Scheme 9). 59 The reaction works through a similar mechanism shown in previous examples, affording optically active chroman-2-ones 25. Although the reaction yields and the enantiocontrol of the process are high, the scope is rather limited.…”

Special Issue: Asymmetry and Symmetry in Organic Chemistry

“…Contribution [4] describes a synthesis of chiral, enantiomerically pure aziridine phosphines and their use as chiral catalysts in the intramolecular Rauhut-Currier reaction (a vinylogous Morita-Baylis-Hillman reaction). The desired chiral phenols achieved high chemical yields values with a high degree of enantioselectivity.…”