Hydrogenation of gossypol catalyzed by supported noble metals

• Published in: Tetrahedron letters Vol. 61; no. 51; pp. 152630 - 152633
• Main Authors: Täufer, Amely, Michalik, Dirk, Dinh Tien, Vu, Khac Vu, Tran, Vogt, Markus, Köckritz, Angela
• Format: Journal Article
• Language: English
• Published: OXFORD Elsevier Ltd 17.12.2020; Elsevier
• Subjects: Axial chirality; Chemistry; Chemistry, Organic; Gossypol; Heterogeneous catalysis; Hydrogenation; NMR; Physical Sciences; Science & Technology; Supported noble metal catalysts; Heterogeneous catalysis; Supported noble metal catalysts; NMR; Gossypol; Hydrogenation; Axial chirality
• ISSN: 0040-4039; 1873-3581
• DOI: 10.1016/j.tetlet.2020.152630

[Display omitted] •The hydrogenation of atropisomeric gossypol to a new derivative gossoxol was carried out for the first time.•The most active and selective catalyst was 5 wt% Rh/C.•Plausible intermediates of the catalytic cycle were determined by tracking the hydrogenation using 1H NMR spectroscopy. The hydrogenation of gossypol using supported noble metal catalysts led to a new derivative named gossoxol in 5 to 69% yield. The most active and selective catalyst was 5 wt% Rh/C. The mechanism of the hydrogenation was discussed and plausible intermediates of the catalytic cycle were determined by tracking the behavior of gossypol in different solvents and at elevated temperature using 1H NMR spectroscopy. The hydrogenation of anhydrogossypol also led to gossoxol, therefore it was regarded as an intermediate.