91177-70-7

Upstream product

• 116696-50-5 Acetic acid (E)-(S)-1-methyl-2-oxo-4-phenyl-but-3-enyl ester 
• 91111-03-4 1-phenyl-4-(tetrahydropyran-2-yloxy)-1-penten-3-one 
• 3909-96-4 (1E,3E)-1-phenyl-1,3-pentadiene 
• 14371-10-9 (E)-3-phenylpropenal 
• 75927-49-0 pinacol vinylboronate 
• 113-24-6 sodium pyruvate 
• 95832-93-2 (S)-3-oxo-5-phenylpent-4-en-2-yl acetate 
• 119420-93-8 Acetic acid (E)-(S)-2-hydroxy-1-methyl-4-phenyl-but-3-enyl ester 
• 92215-95-7 3-hydroxy-5-phenyl-4-penten-2-one 
• 50-99-7 D-glucose 

Downstream Products

• 100560-62-1 2-Methyl-3-((E)-styryl)-1,4-dioxa-spiro[4.5]decane 
• 73494-49-2 (2R)-5-Phenyl-2-pentanol 
• 2344-71-0 (S)-(+)-5-phenyl-2-pentanol 
• 116696-54-9 (3R,4S,1E)-3,4-(cyclohexylidenedioxy)-1-phenyl-1-pentene 
• 116696-53-8 (3S,4S,1E)-3,4-(cyclohexylidenedioxy)-1-phenyl-1-pentene 

Relevant academic research and scientific papers

Copper-Catalyzed Tandem Hydrocupration and Diastereo- and Enantioselective Borylalkyl Addition to Aldehydes

We report the copper-catalyzed stereoselective addition of in situ generated chiral boron-α-alkyl intermediates to various aldehydes including α,β-unsaturated aldehydes under mild conditions. This tandem and multicomponent method facilitated the synthesis of enantiomerically enriched 1,2-hydroxyboronates bearing contiguous stereocenters in good yield with high diastereo- and enantioselectivity up to a ratio greater than 98:2. In particular, α,β-unsaturated aldehydes were successfully used as electrophiles in Cu?H catalysis through 1,2-addition without significant reduction. The resulting 1,2-hydroxyboronates were used in various transformations.

Enantio- and diastereoselective synthesis of 1,2-hydroxyboronates through Cu-Catalyzed additions of alkylboronates to aldehydes

The first catalytic enantio- and diastereoselective synthesis of 1,2-hydroxyboronates is reported. Reactions are promoted by a readily available chiral monodentate phosphoramidite-copper complex in the presence of an alkyl 1,1-diboron reagent. Products contain two contiguous stereogenic centers and are obtained in up to 91% yield, >98:2 d.r., and 98:2 e.r. The reaction is tolerant of aryl and vinyl aldehydes, and the 1,2-hydroxyboronate products can be transformed into versatile derivatives. Mechanistic experiments indicate control of absolute stereochemistry of the α-boryl component.

Extractive biocatalysis: A powerful tool in selectivity control in yeast biotransformations

The effect of absorbing resins on the yeast reduction of α,β- unsaturated carbonyl compounds is reported. Enantioselectivity, chemoselectivity and space-time yields of the biotransformation are impressively enhanced. The distribution of substrates and products between the resin and the water phase shows that the improved selectivity has to be attributed to the control of substrate concentration.

Improved Conditions for the production and Chatacterization of 1-Arylpropane-1,2-diols and Related Compounds

Improved conditions for the production and characterization of 1-arylpropane-1,2-diols and related compounds were developed.Experimental conditions providing highly enhanced activity of pyruvate decarboxylase in bakers' yeast in the presence of pyruvate, thiamine pyrophosphate, and magnesium(II) salt were applied to the preparation of (R)-1-hydroxy-1-phenyl-2-propanone from benzaldehyde.Subsequent reduction with bakers' yeast efficiently afforded 1-phenyl-1,2-propanediol (35percent).The composition of its stereoisomers was precisely determined, and the major (1R,2S)-isomer (89percent of the total mixture) could be isolated by recrystallizing the corresponding benzoate.The analytical method for identifying the stereoisomeric composition was also effective for the determination of 5-phenyl-4-pentene-2,3-diol, the biotransformation product from cinnamaldehyde, the vinylogous substrate of benzaldehyde.Furthermore, the structural characterization of 1(2-furyl)propane-1,2-diol, which was obtained from furfural (28percent) by the action of brewers' yeast Saccharomyces cerevisiae (carlsbergensis), is described.The major (1S,2S)-isomer could be isolated by recrystallizing the crude product.

Selective Asymmetric Dihyroxylation of Polyenes

The asymmetric dihydroxylation procedure (AD) is applied to a variety of polyenes.In many cases excellent regioselectivities are obtained.The observed selectivities are rationalized in terms of electronic and/or steric inherent to the substrate, superimposed on the substrate's favorable or unfavorable interactions with the binding pocket of the AD ligand.Surprisingly, for medium and large ring olefins with trans-double bonds outstanding enantioselectivities are realized using the pyrimidine ligands.A hexaol of D3 symmetry is prepared from all trans cyclodecatriene.

Fluoride Ion Catalyzed Reduction of Aldehydes and Ketones with Hydrosilanes. Synthetic and Mechanistic Aspects and an Application to the Threo-Directed Reduction of α-Substituted Alkanones

Reduction of aldehydes and ketones with hydrosilanes proceeded in the presence of a catalytic amount of tetrabutylammonium fluoride or tris(diethylamino)sulfonium difluorotrimethylsilicate in aprotic polar solvents under mild conditions.A significant isotope effect (kH/kD = 1.50) was observed in competitive reduction of acetophenone with HSiMe2Ph and DSiMe2Ph.The reaction was of first order in the concentration of an aprotic polar solvent HMPA.Reduction of 2-methylcyclohexanone gave cis-2-methylcyclohexanol with selectivities up to 95percent.The kinetic and stereochemical results suggest that a hexavalent fluorosilicate - is involved. α-Alkoxy (acyloxy or dimethylamino) ketones were transformed to threo alcohols in high diastereoselectivities.The reduction was also applied to α-methyl-β-keto amides, RCOCH(MeCONR)2, to afford the corresponding threo alcohols in >98percent selectivity.The threo selectivity is explained in terms of the Felkin-Anh model in which interaction of carbonyl oxygen with a countercation is ideally suppressed.The threo-directed reduction was applied to (R)-1-phenyl-4-(2-tetrahydropyranyloxy)-1-penten-3-one and N-(2-benzoylpropanoyl)piperidine.The resulting threo alcohols were respectively converted into (2R,3S)-2,3-(cyclohexylidenedioxy)butanal, a key intermediate of daunosamine synthesis, and into a pharmacologically useful compound threo-N-(3-hydroxy-2-methyl-3-phenylpropyl)piperidine.

SYNTHESIS OF 1-SUBSTITUTED (S)-4-ACETOXY-1-PENTEN-3-ONES USING (S)-LACTIC ACID AS A CHIRAL SOURCE AND THEIR SYNTHETIC REACTIONS

Ylide reaction of (S)-3-acetoxy-1-triphenylphosphoranylidene-2-butanone, derived from (S)-lactic acid, with aldehydes gives 1-substituted (S)-4-acetoxy-1-penten-3-one derivatives, which are shown to be transformed into useful chiral compouds by stereosele

On the Steric Course of Bakers's Yeast Reduction of α-Hydroxy Ketones

The baker's yeast mediated conversion of the α-hydroxy ketones 1-6 into the diols 8-14 is reported.