56503-12-9

Upstream product

• 4192-77-2 ethyl cinnamate 
• 2272-55-1 ethyl trans-3-phenyl-1-oxirane-2-carboxylate 
• 103-36-6 ethyl 3-phenyl-2-propenoate 
• 133421-01-9 3-(Dimethylthexylsiloxy)-3-phenyl-2-(trimethylsiloxy)propannitril 
• 18632-39-8 ethyl 2-hydroxy-3-phenyl-3-oxopropanoate 
• 64-17-5 ethanol 
• 5695-95-4 (R)-2,3-Dihydroxy-3-phenyl-propionic acid 

Downstream Products

• 133521-66-1 (4S,5R)-Ethyl 2,2-dimethyl-5-phenyl-1,3-dioxolane-4-carboxylate 
• 133421-02-0 erythro-2,2-Dimethyl-5-phenyl-1,3-dioxolan-4-carbonsaeure-ethylester 
• 137905-94-3 (2S,3S)-3-Hydroxy-3-phenyl-2-phenylsulfanyl-propionic acid ethyl ester 

Relevant academic research and scientific papers

Biotransformations with baker's yeast: pH effects on diastereoselectivity during α-hydroxy-β-ketoester reductions and carbon-carbon bond cleavages

Baker's yeast mediated reduction of α-substituted-β-ketoesters lead to reduction of the carbonyl group with high enantiospecificity and diastereoselectivity at low pH (4.0-5.0, e.e. >99%, d.e. >90%) but cleavage of the C-C bond is observed at higher pH >8.0). Similar carbon-carbon bond cleavages are observed in the reactions of α-acetamido-β-ketoesters and acetamidocinnamic acid.

Osmium on chelate resin: Nonvolatile catalyst for the synthesis of DIOLS from alkenes

Osmium tetraoxide (OsO4) was immobilized on a commercially available chelate resin DIAION CR11 (CR11) just by simply immersing it in a methanol solution of OsO4 at room temperature. The resulting purple solid, 5% Os/CR11, indicated no volatility, and effectively catalyzed the oxidation of various alkenes to the corresponding diols.

Synthesis of amino thiols and isocysteines via regioselective ring opening of sulfamidates with tetrathiomolybdate

Herein we present a simple and highly efficient method for the synthesis of β and γ-amino thiols via regioselective ring opening of sulfamidates with tetrathiomolybdate 1. The generality of this methodology has been shown by synthesizing carbohydrate deri

Gelozymes in organic synthesis. Part IV: Resolution of glycidate esters with crude Mung bean (Phaseolus radiatus) epoxide hydrolase immobilized in gelatin matrix

A crude extract of Mung bean meal (Phaseolus radiatus) possessing epoxide hydrolase activity immobilized in gelatin gel (gelozyme) is employed in the stereoselective epoxide ring opening of glycidate esters. Thus, ethyl trans-(±)-3-phenyl glycidate 1a and methyl trans-(±)-3-(4-methoxyphenyl) glycidate 1b gave (2S,3R)-glycidate esters (ee >99% and 45% yield) with gelatin immobilized enzyme in diisopropyl ether. The corresponding (2R,3S)-enantiomer of 1a was hydrolyzed by an epoxide hydrolase to predominantly give the anti-product, ethyl (2R,3R)-2,3-dihydroxy-3-phenylpropanoate, with a diastereomeric excess of 78% and ee 94% (40%). A small amount (5%) of racemic syn-product was also obtained as a result of the spontaneous hydrolysis. In the case of 1b, the hydrolysis product was racemic due to high reactivity of the glycidate toward water.

Alkene cis-dihydroxylation by [(Me3tacn)(CF3CO 2)RuVIO2]CIO4 (Me3tacn = 1,4,7-trimethyl-1,4,7-triazacyclononane): Structural characterization of [3 + 2] cycloadducts and kinetic studies

cis-Dioxoruthenium(VI) complex [(Me3tacn)(CF3CO 2)RuVIO2]CIO4 (1, Me3tacn = 1,4,7-trimethyl-1,4,7-triazacyclononane) reacted with alkenes in aqueous tert-butyl alcohol to afford cis-1,2-diols in excellent yields under ambient conditions. When the reactions of 1 with alkenes were conducted in acetonitrile, oxidative C=C cleavage reaction prevailed giving carbonyl products in >90% yields without any cis-diol formation. The alkene cis-dihydroxylation and C=C cleavage reactions proceed via the formation of a [3 + 2] cycloadduct between 1 and alkenes, analogous to the related reactions with alkynes [Che et al. J. Am. Chem. Soc. 2000, 122, 11380], With cyclooctene and trans-β-methylstyrene as substrates, the Ru(III) cycloadducts [(Me3tacn)(CF 3CO2)RuIIIO(H)CH(CH2) 6HCO]CIO4 (4a) and [(Me3tacn)(CF 3CO2)RuIIIO(H)-PhCHCH(CH3)O]CIO 4 (4b) were isolated and structurally characterized by X-ray crystal analyses. The kinetics of the reactions of 1 with a series of p-substituted styrenes has been studied in acetonitrile by stopped-flow spectrophotometry. The second-order rate constants varied by 14-fold despite an overall span of 1.3 V for the one-electron oxidation potentials of alkenes. Secondary kinetic isotope effect (KIE) was observed for the oxidation of β-d2-styrene (kH/kD = 0.83 ± 0.04) and α-deuteriostyrene (kH/kD = 0.96 ± 0.03), which, together with the stereoselectivity of cis-alkene oxidation by 1, is in favor of a concerted mechanism.

Ruthenium nanoparticles supported on hydroxyapatite as an efficient and recyclable catalyst for cis-dihydroxylation and oxidative cleavage of alkenes

Impregnation of hydroxyapatite with colloidal ruthenium results in the formation of a catalyst that effects cis-dihydroxylation and oxidative cleavage of alkenes to their respective cis-1,2-diols and carbonyl products in good to excellent yields (see scheme). The supported ruthenium catalyst can be easily recycled and reused for consecutive reaction runs without significant deterioration of the catalytic activities. R1, R2 = H, alkyl, aryl.

Electronic effects in olefin oxidation by imidoosmium(VIII) compounds

Imido osmium(VIII) complexes are versatile oxidants for C-C double bond functionalisation. Despite their structural similarity with OsO4 their reactivity cannot always be compared with this seminal reagent. Detailed investigations including kinetic competition experiments are presented that uncover the electronic and steric preferences of osmium imido complexes. The different behaviour of OsO4 and its imido derivatives towards tertiary amines and diamines is clarified. Hammett correlation studies reveal that the reactivity spectrum of the respective oxidants ranges from a strongly electrophilic behaviour in the case of OsO4 to a rather nucleophilic character as encountered for OsO(NtBu)3. Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004.

Direct catalytic asymmetric aldol-type reaction of aldehydes with ethyl diazoacetate

(Matrix presented) The direct aldol-type condensation of aldehydes with ethyl diazoacetate catalyzed by the chiral complex of BINOL derivatives-Zr(OtBu)4 gave β-hydroxy α-diazo carbonyl compounds with moderate enantioselectivities (5

Stereoselective and regioselective reaction of cyclic ortho esters with phenols

Cyclic ortho esters undergo stereoselective and regioselective reaction with phenols when treated with BF3·OEt2 at low temperatures. Attack of the phenol on the ortho ester occurs at an open carbon para to electron-donating groups on the phenol ("C-addition") or at the phenolic hydroxyl group ("O-addition") depending on the nature of the cation formed from reaction of the ortho ester and BF3·OEt2. Products resulting from O-addition undergo reversion to a mixture of starting phenol, C-addition product, and O-addition product if treated with BF3·OEt2 at room temperature, but C-addition products are stable under the same conditions. X-ray structural analysis of the C-addition compound indicates that its stereochemistry is opposite to that observed in reaction of similar ortho esters with chloride from TMSCl. However, the stereochemistry of the reaction can be rationalized by the ability of the ortho ester to isomerize via an intermediate benzylic cation and examination of the preferred trajectory of attack of the nucleophile on the intermediate oxonium ion.

Solvent effect on ruthenium catalyzed dihydroxylation

The effect of different solvents on flash dihydroxylation is compared and for the first time, the replacement of ethyl acetate with acetone was shown to give a successful, catalytic cis-dihydroxylation of the alkene moiety in cholesteryl acetate and the ruthenium catalytic cycle could be maintained by methanesulfonamide in the absence of acetonitrile.