95614-86-1

Upstream product

• 95614-76-9 ethyl-(R)-(+)-(p-toluenesulfinyl)-N-methoxy-acetimidate 
• 78-84-2 isobutyraldehyde 
• 7152-15-0 ethyl 4-methyl-3-oxo-pentanoate 
• 64-17-5 ethanol 
• 93617-86-8 (4S)-(+)-3-bromoacetyl-4-(1-methylethyl)-2-oxazolidinone 
• 141-52-6 sodium ethanolate 
• 623-48-3 ethyl iodoacetae 

Downstream Products

• 1310533-95-9 (R)-3-hydroxy-4-methylpentyl 4-methylbenzenesulfonate 

Relevant academic research and scientific papers

Asymmetric hydrogenation reactions using a practical in situ generation of chiral ruthenium-diphosphine catalysts from anhydrous RuCl3

A very simple in situ preparation of chiral ruthenium-diphosphine catalyst from anhydrous RuCl3 is reported. Prochiral C = O and C = C bonds have been reduced with high enantioselectivities via ruthenium-catalyzed hydrogenation.

Asymmetric reformatsky reaction of aldehydes catalyzed by novel β -amino alcohols and zinc complexes

A series of β-amino alcohols derived from (1R, 2S)-2-amino-1,2- diphenylethanol and substituted salicylaldehydes as novel chiral tridentate ligands has been applied to an asymmetric Reformatsky reaction of aldehydes with ethyl iodoacetate in the presence

Highly enantioselective double reduction of phenylglyoxal to (R)-1-phenyl-1,2-ethanediol by one NADPH-dependent yeast carbonyl reductase with a broad substrate profile

The activity and enantioselectivity of a carbonyl reductase from Pichia pastoris GS115 were evaluated with a series of carbonyl compounds including aryl aldehydes, ketones, α- and β-ketoesters. This recombinant enzyme possessed a broad substrate profile with the ability of reducing both aldehydes and ketones. Especially, the enzyme catalyzed the double reduction of phenylglyoxal to (R)-1-phenyl-1,2-ethanediol with 99% yield and 99% ee by coupling with d-glucose dehydrogenase for the regeneration of cofactor NADPH, representing the first example of effective reduction of both aldehyde and ketone functional groups in one molecule by using only one enzyme. Furthermore, this study provides valuable information for guiding the future application of this versatile biocatalyst.

Chiral iridium catalysts bearing spiro pyridine-aminophosphine ligands enable highly efficient asymmetric hydrogenation of β-aryl β-ketoesters

Tons of TONs: Chiral iridium catalysts bearing ligand 1 are highly efficient for the asymmetric hydrogenation of β-substituted β-ketoesters. The product β-hydroxyesters are delivered in high yield with excellent enantioselectivities and high turnover numbers (TONs). cod= 1,5-cyclooctadiene.

Bisoxazolidine-catalyzed enantioselective reformatsky reaction

A readily available chiral bisoxazolidine catalyzes the asymmetric Reformatsky reaction between ethyl iodoacetate and aldehydes. In the presence of 10 mol % of the ligand, dimethylzinc, and air, this method produces ethyl 3-hydroxy-3-(4-aryl)propanoates in high yields and in 75 to 80% ee at room temperature within 1 h. In contrast to aromatic substrates, relatively low ee's are obtained with aliphatic aldehydes.

Enzymatic ketone reduction: mapping the substrate profile of a short-chain alcohol dehydrogenase (YMR226c) from Saccharomyces cerevisiae

A short-chain alcohol dehydrogenase (YMR226c) from Saccharomyces cerevisiae was cloned and expressed in Escherichia coli, and the encoded protein was purified. The activity and enantioselectivity of this recombinant enzyme were evaluated with a series of ketones. The alcohol dehydrogenase (YMR226c) was found to effectively catalyze the enantioselective reductions of aryl-substituted acetophenones, α-chloroacetophenones, aliphatic ketones, and α- and β-ketoesters. While the enantioselectivity for the reduction of β-ketoesters was moderate, the acetophenone derivatives, aromatic α-ketoesters, some substituted α-chloroacetophenones, and aliphatic ketones were reduced to the corresponding chiral alcohols with excellent enantioselectivity. The enantiopreference of this enzyme generally followed Prelog's rule for the simple ketones. The ester functionality played some role in determining the enzyme's enantiopreference for the reduction of α- and β-ketoesters. The present study serves as a valuable guidance for the future applications of this versatile biocatalyst.

A recombinant ketoreductase tool-box. Assessing the substrate selectivity and stereoselectivity toward the reduction of β-ketoesters

The substrate selectivity and stereoselectivity of a series of ketoreductases were evaluated toward the reduction of two sets of β-ketoesters. Both the structural variety at β-position and the substituent at α-position greatly affected the activity and stereoselectivity of these ketoreductases. For the first set of β-ketoesters, at least one ketoreductase was found that catalyzed the formation of either (d) or (l) enantiomer of β-hydroxyesters from each substrate with high optical purity, with the only exception of ethyl (d)-3-hydroxy-3-phenylpropionate. For the second set of β-ketoesters with α-substituents, the situation is more complex. More commonly, a ketoreductase was found that formed one of the four diastereomers in optically pure form, with only a few cases in which enzymes could be found that formed two or more of the diastereomers in high optical purity. The continued development of new, more diverse ketoreductases will create the capability to produce a wider range of single diastereomers of 2-substituted-3-hydroxy acids and their derivatives.

Rhodium and ruthenium complexes of 1,1′-bis(phosphetano)ferrocenes: Structural characterisation and catalytic behaviour

The first structural characterisation of ruthenium and rhodium complexes of the 1,1′-bis(phosphetano)ferrocenes 1 (FerroTANEs) - namely [{(S,S)-iPr-1}RuCl2Py2] and [{(S,S)iPr-1}Rh(COD)OTf] - is reported, X-ray data show that the ruthenium complex and the rhodium chelate complex both adopt δ conformations, as a result of the (S,S) configuration of the phosphetane moiety. The ruthenium complexes promote the catalytic hydrogenation of β-keto esters with moderate to high enantioselectivities. The behaviour of the rhodium complexes of 1 is compared with that of other phosphetane-based catalysts in the hydrogenation of methyl N-acetamidocinnamate. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2003.

Synthesis of a new class of chiral 1,5-diphosphanylferrocene ligands and their use in enantioselective hydrogenation

A new family of ferrocenylphosphane ligands has been prepared. Their flexible synthesis allows many structural modifications. The asymmetric induction of these ligands was examined in the hydrogenation of functionalized C=C, C=O, and C=N bonds. The enantioselectivity of the reaction was strongly dependent on the substituent R at the position α to the ferrocene moiety. In many cases, both enantiomeric β-hydroxyesters of the reduction product can be obtained by simply replacing a dimethylamino group in the ligand with a methyl group.

Chiral 1,2-bis(phosphetano)ethanes

Optically pure 1,2-bis(phosphetano)ethanes 3 (BPE-4) have been prepared from 1,2-bis(phosphino)ethane and the cyclic sulfates of symmetrical anti-1,3-diols. Diphosphine 3c (R = cyclohexyl) is an easily accessible, air-stable chiral ligand. Its suitability to the ruthenium-catalysed hydrogenation of functionalised ketones has been examined by using several catalyst precursors. Significant enantiomeric excesses were obtained. A ruthenium complex containing two coordinated diphosphines 3c was characterised by X-ray diffraction studies.