Desimoni, Giovanni; Faita, Giuseppe; Filippone, Salvatore; Mella, Mariella; Zampori, Maria Grazia; Zema, Michele published their research in Tetrahedron on December 17 ,2001. The article was titled 《A new and highly efficient catalyst for the enantioselective Mukaiyama-Michael reaction between (E)-3-crotonoyl-1,3-oxazolidin-2-one and 2-trimethylsilyloxyfuran》.Name: 2,6-Bis((4S,5S)-4,5-diphenyl-4,5-dihydrooxazol-2-yl)pyridine The article contains the following contents:
The Mukaiyama-Michael reaction between 2-trimethylsilyloxyfuran and (E)-3-crotonoyl-1,3-oxazolidin-2-one has been stereoselectively catalyzed by several optically active complexes based on bis(oxazoline) (box) or pyridine bis(oxazoline) (pybox) chiral ligands and metal cations. The catalysts derived from the newly synthesized 2,6-bis[(4’R,5’R)-diphenyl-1,3-oxazolin-2′-yl]pyridine (I) and the triflates of EuIII, LaIII, CeIV were highly efficient: the diastereoselectivity was entirely anti and the enantioselectivity was excellent (ranging from 98 to >99%). A mechanistic insight into the nature of the activated substrate-catalyst complex was inferred studying the lanthanum complexes with 1H and 13C NMR spectroscopy. Based on these results and on the crystallog. structure of the complex between pybox and La(OTf)3, a stereochem. model is proposed to rationalize the crucial role of the substituent in position 5, suitably placed to blind the Si-face of the coordinated reagent. The results came from multiple reactions, including the reaction of 2,6-Bis((4S,5S)-4,5-diphenyl-4,5-dihydrooxazol-2-yl)pyridine(cas: 410092-98-7Name: 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. The ring atoms in the pyridine molecule are sp2-hybridized. The nitrogen is involved in the π-bonding aromatic system using its unhybridized p orbital. Name: 2,6-Bis((4S,5S)-4,5-diphenyl-4,5-dihydrooxazol-2-yl)pyridine Pyridine has a conjugated system of six π electrons that are delocalized over the ring.