139616-52-7

Upstream product

• 609-14-3 2-acetylpropanoic acid ethyl ester 
• 57794-08-8 (1S,2S)-trans-1,2-Cyclohexanediol 
• 100-39-0 benzyl bromide 
• 340039-86-3 ethyl (2RS)-3,3-<(S,S)-cyclohexane-1,2-dioxy>-2-methylbutanoate 

Downstream Products

• 89656-86-0 ethyl (S)-2-benzyl-2-methyl-3-oxobutyrate 
• 116562-88-0 (R)-N-acetyl-α-methylphenylalanine ethyl ester 

Relevant academic research and scientific papers

Asymmetric synthesis of α,α-disubstituted α-amino acids using (S,S)-cyclohexane-1,2-diol as a chiral auxiliary

Diastereoselective alkylation of ethyl 2-methyl- and/or 2-ethylacetoacetates using the (S,S)-cyclohexane-1,2-diol as an acetal chiral auxiliary afforded enol ethers (2a-f and 5a-f) of 92->95% de in 31-70% yields. Removal of the cyclohexane-1,2-diol with BF3-OEt2 afforded β-keto esters (3 and 6) bearing a chiral quaternary carbon. The β-keto esters could be easily converted into optically active α-methylated and/or α-ethylated α,α-disubstituted amino acids (12 and 13) in 21-99% yields using Schmidt rearrangement.

Asymmetric Alkylation Using Chiral Cyclic Diols to Prepare a Quaternary Carbon

Asymmetric alkylation of cyclic and acyclic β-keto ester acetals (4, 5, 13, 14, and 18) with C2-symmetric cycloalkane-1,2-dioxy moiety proceeded in a highly diastereoselective manner to afford enol ethers (9-12, 15-17, 19a-c) with a chiral quat

Application of chiral cyclic diols to asymmetric alkylation

Chiral cyclic (6- or 7-membered ring) diols were found to be excellent chiral auxiliaries for asymmetric alkylation of cyclic (or acyclic) β-keto esters.