60218-91-9

Upstream product

• 100-52-7 benzaldehyde 
• 123-38-6 propionaldehyde 
• 79-03-8 propionyl chloride 
• 1361146-59-9 (4R,5S,E)-4-methyl-5-phenylpent-2-ene-1,5-diol 

Downstream Products

• 127379-92-4 (1S,2R)-2-methyl-1-phenyl-propane-1,3-diol 
• 71699-32-6 (2SR,3SR)-3-Hydroxy-3-phenyl-2-methylpropanal 
• 71699-31-5 (2RS,3SR)-3-Hydroxy-3-phenyl-2-methylpropanal 
• 101-39-3 2-methyl-3-phenyl-2-propenal 

Relevant academic research and scientific papers

Engineering a Promiscuous Tautomerase into a More Efficient Aldolase for Self-Condensations of Linear Aliphatic Aldehydes

The enzyme 4-oxalocrotonate tautomerase (4-OT) from Pseudomonas putida mt-2 takes part in a catabolic pathway for aromatic hydrocarbons, where it catalyzes the conversion of 2hydroxyhexa-2,4-dienedioate into 2-oxohexa-3-enedioate. This tautomerase can also promiscuously catalyze carbon–carbon bond-forming reactions, including various types of aldol reactions, by using its amino-terminal proline as a key catalytic residue. Here, we used systematic mutagenesis to identify two hotspots in 4-OT (Met45 and Phe50) at which single mutations give marked improvements in aldolase activity for the self-condensation of propanal. Activity screening of a focused library in which these two hotspots were varied led to the discovery of a 4-OT variant (M45Y/F50V) with strongly enhanced aldolase activity in the self-condensation of linear aliphatic aldehydes, such as acetaldehyde, propanal, and butanal, to yield α,β-unsaturated aldehydes. With both propanal and benzaldehyde, this double mutant, unlike the previously constructed single mutant F50A, mainly catalyzes the self-condensation of propanal rather than the cross-condensation of propanal and benzaldehyde, thus indicating that it indeed has altered substrate specificity. This variant could serve as a template to create new biocatalysts that lack dehydration activity and possess further enhanced aldolase activity, thus enabling the efficient enzymatic self-coupling of aliphatic aldehydes.

Catalytic Asymmetric Iterative/Domino Aldehyde Cross-Aldol Reactions for the Rapid and Flexible Synthesis of 1,3-Polyols

We report here catalytic asymmetric iterative and domino cross-aldol reactions between aldehydes, endowed with a high level of robustness, flexibility, and generality. A Cu(I)-DTBM-SEGPHOS complex catalyzes an asymmetric cross-aldol reaction between acceptor aldehydes and boron enolates derived from donor aldehydes, which are generated through Ir-catalyzed isomerization of allyloxyboronates. The unit process can be repeated using the aldol products in turn as acceptor substrates for the subsequent asymmetric aldol reaction. The donor aldehydes and stereoselectivity can be flexibly switched in a stepwise manner for the double-aldol reaction. Furthermore, asymmetric triple- and quadruple-aldol reactions are possible in one-pot using the appropriate amounts of donors and amine additives, rapidly elongating the carbon skeleton with controlling up to eight stereocenters. The method should be useful for straightforward synthesis of enantiomerically and diastereomerically enriched 1,3-polyols.

Catalytic enantioselective 1,2-diboration of 1,3-dienes: Versatile reagents for stereoselective allylation

More with boron: The development of catalytic enantioselective 1,2-diboration of 1,3-dienes enables a new strategy for enantioselective carbonyl allylation reactions (see scheme). These reactions occur with outstanding levels of stereoselection and can be applied to both monosubstituted and 1,1-disubstituted dienes. The carbonyl allylation reactions provide enantiomerically enriched functionalized homoallylic alcohol products. Copyright

DIRECT, ENANTIOSELECTIVE ALDOL COUPLING OF ALDEHYDES USING CHIRAL ORGANIC CATALYSTS

Nonmetallic, chiral organic catalysts are used to catalyze an enantioselective aldol coupling reaction between aldehyde substrates. The reaction may be carried out with a single enolizable aldehyde, resulting in dimerization to give a β-hydroxy aldehyde,

The first direct and enantioselective cross-aldol reaction of aldehydes

The first enantioselective catalytic direct cross-aldol reaction that employs nonequivalent aldehydes has been accomplished using proline as the reaction catalyst. Structural variation in both the aldol donor (R1 = Me, n-Bu, Bn, 91 to >99%) and aldol acceptor (R2 = I-Pr, I-Bu, c-C6H11, Et, Ph, 97-99% ee) are possible while maintaining high reaction efficiency (75-88% yield). Significantly, this new aldol variant allows facile enantioselective access to a broad range of β-hydroxy aldehydes which are valuable intermediates in polyketide syntheses. Copyright

Aldol reactions on solid phase. Sc(OTf)3-catalyzed aldol reactions of polymer-supported silyl enol ethers with aldehydes providing convenient methods for the preparation of 1,3-diol, β-hydroxy carboxylic acid, and β-hydroxy aldehyde libraries

Aldol reactions on solid phase have been achieved. In the presence of a catalytic amount of scandium triflate (Sc(OTf)3), polymer-supported silyl enol ethers reacted with aldehydes to afford the corresponding β-hydroxy thioester derivatives, which were reduced to 1,3-diol and β-hydroxy aldehyde derivatives, or hydrolyzed to β-hydroxy carboxylic acid derivatives.