192565-59-6

Upstream product

• 31469-15-5 1-methoxy-2-methyl-1-trimethylsiloxy-1-propene 
• 117909-29-2 N-4-chlorobenzylidene-2-hydroxyaniline 
• 117909-29-2 (E)-N-(4-chlorobenzylidene)-2-hydroxyaniline 

Relevant academic research and scientific papers

(R)-6,6′-Bis(trifluoromethanesulfonyl)-2,2′-dihydroxy-1,1′-binaphthyl: a new ligand for asymmetric synthesis

The new (R)-6,6′-bis(trifluoromethanesulfonyl)-2,2′-dihydroxy-1,1′-binaphthyl (1) has been synthesized and proved to generate highly active zirconium-based catalysts for asymmetric Mannich-type reactions.

A Powerful Chiral Phosphoric Acid Catalyst for Enantioselective Mukaiyama–Mannich Reactions

A new BINOL-derived chiral phosphoric acid bearing 2,4,6-trimethyl-3,5-dinitrophenyl substituents at the 3,3′-positions was developed. The utility of this chiral phosphoric acid is demonstrated by a highly enantioselective (ee up to >99 %) and diastereoselective (syn/anti up to >99:1) asymmetric Mukaiyama–Mannich reaction of imines with a wide range of ketene silyl acetals. Moreover, this method was successfully applied to the construction of vicinal tertiary and quaternary stereogenic centers with excellent diastereo- and enantioselectivity. Significantly, BINOL-derived N-triflyl phosphoramide constitutes a complementary catalyst system that allows the title reaction to be applied to more challenging imines without an N-(2-hydroxyphenyl) moiety.

Chiral Bronsted acid catalyzed enantioselective Mannich-type reaction

Mannich-type reaction of ketene silyl acetals with aldimines proceeded catalytically by means of a phosphoric acid diester, derived from (R)-BINOL, as a chiral Bronsted acid to afford β-amino esters with good diastereoselectivity in favor of the syn isomer and high enantioselectivity (up to 96% ee). The highest enantioselectivity was achieved by the phosphoric acid diester bearing 4-nitrophenyl groups on the 3,3′-positions of BINOL. The N-2-hydroxyphenyl group of aldimine was found to be essential for the present Mannich-type reaction. In combination with these experimental investigations, two possible monocoordination and dicoordination pathways were explored using density functional theory calculations (BHandHLYP/6-31G*). The present reaction proceeds via a dicoordination pathway through the zwitterionic and nine-membered cyclic transition state (TS) consisting of the aldimine and the phosphoric acid. The re-facial selectivity was also well-rationalized theoretically. The nine-membered cyclic structure and aromatic stacking interaction between the 4-nitrophenyl group and N-aryl group would fix the geometry of aldimine on the transition state, and the si-facial attacking TS is less favored by the steric hindrance of the 3,3′-aryl substituents.

Remarkably stable chiral zirconium complexes for asymmetric Mannich-type reactions

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

Chiral zirconium catalysts using multidentate BINOL derivatives for catalytic enantioselective Mannich-type reactions; ligand optimization and approaches to elucidation of the catalyst structure

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

Enantioselective Mannich-type reaction catalyzed by a chiral Bronsted acid

No metal required: The Mannich-type reaction of ketene silyl acetals 2 with aldimines 1 proceeded highly enantioselectively to afford the syn isomer of β-aminoesters 3 with up to 96% ee under the influence of a chiral Bronsted acid 4 derived from (R)-BINO

Air-stable, storable, and highly selective chiral Lewis acid catalyst

(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.

Enantioselective mannich-type reactions using a novel chiral zirconium catalyst for the synthesis of optically active β-amino acid derivatives

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,