Suga, Hiroyuki; Sekikawa, Yurie; Misawa, Shunta; Kinugawa, Daito; Oda, Rinnosuke; Itoh, Kennosuke; Toda, Yasunori; Kiyono, Ryotaro published an article in Journal of Organic Chemistry. The title of the article was 《Chiral Lewis Acid-Catalyzed Enantioselective Cycloadditions between Indoles and Cyclic Carbonyl Ylides Derived from Diazodiketone or Diazoketoester Derivatives》.Safety of 2,6-Bis((4S,5S)-4,5-diphenyl-4,5-dihydrooxazol-2-yl)pyridine The author mentioned the following in the article:
Asym. 1,3-dipolar cycloaddition reactions between N-methylindoles and several cyclic carbonyl ylides that were derived from diazodiketone or diazoketoester precursors in the presence of both achiral Rh and chiral lanthanoid metal catalysts are described. For the six-membered cyclic carbonyl ylides derived from 1-diazo-5-aryl-2,5-pentanedione precursors, the cycloaddition reactions were carried out using Rh2(OAc)4 (2 mol %) and the chiral Pybox-Ph2-Lu(OTf)3 complex (10 mol %) as catalysts, resulting in high enantioselectivities (83% to >98% ee (exo)) along with relatively good exo-selectivities (exo:endo = 65:35 to 94:6) and yields (63-85%). For the five-membered cyclic carbonyl ylide derived from 1-diazo-2,4-pentanedione precursor, the cycloaddition reaction with 5-bromo-1-methylindole was carried out in the presence of Rh2(OAc)4 (2 mol %) and the chiral Pybox-Ph2-Er(OTf)3 complex (30 mol %) as catalysts, resulting in relatively good enantioselectivity (78% ee) and endo-selectivity (endo:exo = 81:19). The experimental process involved the reaction of 2,6-Bis((4S,5S)-4,5-diphenyl-4,5-dihydrooxazol-2-yl)pyridine(cas: 410092-98-7Safety of 2,6-Bis((4S,5S)-4,5-diphenyl-4,5-dihydrooxazol-2-yl)pyridine)
2,6-Bis((4S,5S)-4,5-diphenyl-4,5-dihydrooxazol-2-yl)pyridine(cas: 410092-98-7) belongs to pyridine derivatives. Several pyridine derivatives play important roles in biological systems. While its biosynthesis is not fully understood, nicotinic acid (vitamin B3) occurs in some bacteria, fungi, and mammals. Safety of 2,6-Bis((4S,5S)-4,5-diphenyl-4,5-dihydrooxazol-2-yl)pyridine