304857-39-4Relevant academic research and scientific papers
New Lewis-Basic N-Oxides as Chiral Organocatalysts in Asymmetric Allylation of Aldehydes
Malkov, Andrei V.,Bell, Mark,Orsini, Monica,Pernazza, Daniele,Massa, Antonio,Herrmann, Pavel,Meghani, Premji,Kocovsky, Pavel
, p. 9659 - 9668 (2007/10/03)
Allylation of aromatic and heteroaromatic aldehydes 1a-k with allyltrichlorosilane 2 can be catalyzed by the new heterobidentate, terpene-derived bipyridine N-monoxides 4, 6a,b, and 8-11 (≤10 mol %) to afford (S)-(-)-3 with high enantioselectivities (≤99% ee). The stereochemical outcome has been found to be controlled by the axial chirality of the catalyst, which in turn is determined by the central chirality of the annulated terpene units. Solvent effects on the conversion and the level of asymmetric induction have been elucidated, and MeCN has been identified as the optimal solvent for these catalysts.
PINDY: A novel, pinene-derived bipyridine ligand and its application in asymmetric, copper(I)-catalyzed allylic oxidation
Malkov, Andrei V.,Bella, Marco,Langer, Vratislav,Kocovsky, Pavel
, p. 3047 - 3049 (2007/10/03)
(matrix presented) The title bipyridine ligand (+)-6(PINDY), prepared in five steps from (-)-β-pinene, forms a stable complex with CuCl2 (8) that has been characterized by X-ray crystallography to reveal an unusual geometry at Cu. Triflate 9 proved to catalyze asymmetric allylic oxidation (10 → 11; rt, ～30 min, 49-75% ee).
