2025/03/12 by Eveline H. Tiekink, Ron Verdijk, Trevor A. Hamlin +1 · 1 voice
Chemistry · #Asymmetric Hydrogenation and Catalysis #Asymmetric Synthesis and Catalysis #Axial and Atropisomeric Chirality Synthesis
paper · pdf · doi:10.1002/cplu.202500081
openalex publication_date 2025/03/12 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/01
Abstract We have quantum chemically investigated the catalytic effect of hydrogen bonding organocatalysts, (H 2 N) 2 C=X (X=O, S, Se, NH, PH, AsH, CH 2 , SiH 2 GeH 2 ), such as urea, on the classic Diels‐Alder reaction. All studied hydrogen bond donor catalysts enhance the Diels‐Alder reaction between acrolein and 1,3‐butadiene to a similar extent. Our activation strain and Kohn‐Sham molecular orbital analyses show that these organocatalysts lower the reaction barrier by polarizing the π‐orbitals away from the reactive carbon atoms of acrolein, reducing the Pauli repulsion between the reactants. Interestingly, this catalytic mechanism is not limited to >C=X moieties with relatively electronegative X (e. g., O, S, NH) but extends to situations like >C=CH 2 and even >C=SiH 2 .