192565-60-9Relevant academic research and scientific papers
An air-stable chiral Hf-based catalyst for asymmetric Mannich-type reactions
Kobayashi, Shu,Yazaki, Ryo,Seki, Kazutaka,Ueno, Masaharu
, p. 8425 - 8429 (2008/02/08)
A new class of isolable, air-stable, storable, and Hf-based catalyst has been developed. In the presence of 10 mol % of the powdered Hf catalyst, the asymmetric Mannich-type reactions of imines with silicon enolates derived from esters proceeded smoothly
Remarkably stable chiral zirconium complexes for asymmetric Mannich-type reactions
Saruhashi, Kowichiro,Kobayashi, Shu
, p. 11232 - 11235 (2007/10/03)
Isolable, air-stable, storable, and highly selective chiral zirconium catalysts for asymmetric Mannich-type reactions have been developed. The reactions of imines with silicon enolates proceeded smoothly using 1-10 mol % of the powdered zirconium catalyst
ASYMMETRIC-SYNTHESIS CATALYST BASED ON CHIRAL BROENSTED ACID AND METHOD OF ASYMMETRIC SYNTHESIS WITH THE CATALYST
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Page/Page column 40, (2010/11/08)
A compound usable as an asymmetric synthesis catalyst which can be easily synthesized without using any metal such as a lanthanoid group element; a method of asymmetric synthesis with the compound; and a chiral compound obtained by the asymmetric synthesis method. A Broensted acid is used as a catalyst in asymmetric synthesis, the chiral Broensted acid being represented by formula (1) below or formula (3) below. The asymmetric synthesis method employs the catalyst. Asymmetric synthesis with the catalyst gives a chiral compound.
Chiral zirconium catalysts using multidentate BINOL derivatives for catalytic enantioselective Mannich-type reactions; ligand optimization and approaches to elucidation of the catalyst structure
Ihori, Yoichi,Yamashita, Yasuhiro,Ishitani, Haruro,Kobayashi, Shu
, p. 15528 - 15535 (2007/10/03)
Catalytic enantioselective Mannich-type reactions of silicon enolates with aldimines were investigated using chiral zirconium catalysts prepared from Zr(OtBu)4, N-methylimidazole, and newly designed multidentate BINOL derivatives. Th
A novel dinuclear chiral niobium complex for Lewis acid catalyzed enantioselective reactions: Design of a tridentate ligand and elucidation of the catalyst structure
Kobayashi, Shu,Arai, Kenzo,Shimizu, Haruka,Ihori, Yoichi,Ishitani, Haruro,Yamashita, Yasuhiro
, p. 761 - 764 (2007/10/03)
Two's company: By using a novel chiral ligand a dinuclear chiral niobium catalyst for highly enantioselective Mannich-type reactions was developed. Tridentate binol derivatives provide excellent asymmetric environments around the niobium atom, and the Man
Air-stable, storable, and highly selective chiral Lewis acid catalyst
Ueno, Masaharu,Ishitani, Haruro,Kobayashi, Shu
, p. 3395 - 3397 (2007/10/03)
(matrix presented) An air-stable storable, and highly selective chiral Lewis acid catalyst for asymmetric Mannich-type reactions has been developed. The catalyst can be stored for more than three months in air at room temperature without loss of activity.
A novel chiral zirconium catalyst for enantioselective aldol and Mannich-type reactions. Catalytic activation of both aldehydes and imines using a similar chiral Lewis acid
Kobayashi, Shu,Ishitani, Haruro,Yamashita, Yasuhiro,Ueno, Masaharu,Shimizu, Haruka
, p. 861 - 866 (2007/10/03)
A novel zirconium catalyst has been developed for asymmetric aldol reaction of aldehydes with silyl enolates and asymmetric Mannich reactions of imines with silyl enolates. Similar types of catalysts have been successfully used in both reactions, and the
Enantioselective mannich-type reactions using a novel chiral zirconium catalyst for the synthesis of optically active β-amino acid derivatives
Ishitani, Haruro,Ueno, Masaharu,Kobayashi, Shu
, p. 8180 - 8186 (2007/10/03)
Catalytic enantioselective Mannich-type reactions of silyl enol ethers with aldimines have been successfully performed using a novel chiral zirconium catalyst prepared from zirconium(IV) tert-butoxide (Zr(OrBu)4), 2 equiv of (R)-6,6'-dibromo-1,
