36092-43-0

Upstream product

• 38418-34-7 (E)-2-benzylidene-4-methoxy-4-oxobutanoic acid 
• 38418-34-7 (Z)-2-Benzylidene-4-methoxy-4-oxobutanoic acid 

Downstream Products

• 126121-81-1 C₁₂H₁₆O₃ 

Relevant academic research and scientific papers

Synthesis of versatile building blocks through asymmetric hydrogenation of functionalized itaconic acid mono-esters

The rhodium-catalyzed asymmetric hydrogenation of several β-substituted itaconic acid monoesters, using a library of monodentate phosphoramidite and phosphite ligands is described. Two β-alkylsubstituted substrates were readily hydrogenated by the rhodium complex Rh(COD) 2BF4 in combination with (S)-PipPhos as a ligand resulting in ees of 99 %. In contrast, the corresponding more hindered β-arylsubstituted substrates did not exhibit acceptable enantioselectivities under these conditions. However, the use of a 48-membered ligand library led to the identification of several suitable ligands for these substrates, resulting in ees of 89-99%. The resulting optically active succinic acid derivatives are potentially useful building blocks for more elaborate compounds, because of the ability to differentiate between the carboxylic acid and the ester groups on either side of the molecule.

Catalytic asymmetric alkynylation and arylation of aldehydes by an H 8-binaphthyl-based amino alcohol ligand

A novel chiral H8-1,1'-binaphthyl-based amino alcohol ligand (1Ra,2S,3R)-2 has been synthesized and applied in the direct nucleophilic addition of organozincs (alkynylzinc and arylzinc prepared in situ) to aldehydes, yielding the corresponding optically active propargylic alcohols and diarylmethanols in high yields and good to excellent enantioselectivities. For the asymmetric arylation reaction, one catalyst (1Ra,2S,3R)-2 can afford both enantiomers of many pharmaceutically interesting diarylmethanols by a proper combination of various arylzinc reagents and aldehydes.

Method of preparing optically active homo-beta-amino acids

The present invention is directed to synthesis of homo-β-amino acids of an optical purity sufficient to exhibit optical activity wherein Curtius rearrangement of 3-mono-substituted succinate acid half ester of an optical purity sufficient to exhibit optical activity is affected and the incipient isocyanate is trapped with a primary or secondary alcohol. The resulting carbamate-protected homo-β-amino esters are then saponified to produce the corresponding carbamate-protected homo-β-amino acids which are deprotected to yield homo-β-amino acids of an optical purity sufficient to exhibit optical activity.

Asymmetric Hydrogenation of Prochiral Alkenes Catalysed by Ruthenium Complexes of (R)-(+)-2,2'-Bis(diphenylphosphino)-1,1'-binaphthyl

Two chiral ruthenium(II) complexes containing (R)-(+)-2,2'-bis(diphenylphosphino)-1,1'-binaphthyl were found to be effective catalysts for the asymmetric hydrogenation of 2-acylaminoacrylic and 2-acylaminocinnamic acids under mild conditions, to afford N-acyl-(R)-α-amino acids with 49 - 95 percent optical purity.The differences between the asymmetric hydrogenations effected by RuII- and RhI-(R)-BINAP systems are discussed.Asymmetric hydrogenation of methylenesuccinic acid and its derivatives with Ru-(R)-BINAP is also described.

RUTHENIUM(II)-BINAP COMPLEX CATALYZED ASYMMETRIC HYDROGENATION OF UNSATURATED DICARBOXYLIC ACIDS

Asymmetric hydrogenation of unsaturated dicarboxylic acids employing ruthenium-BINAP complexes as catalyst gave optically active 2-alkylsuccinic acids with high enantioselectivities.