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• 630-19-3 pivalaldehyde 
• 96-09-3 styrene oxide 
• 67210-34-8 1-phenyl-2-phenylsulfanyl-ethanol 
• 13735-81-4 1-styrenyloxytrimethylsilane 
• 3282-30-2 pivaloyl chloride 
• 98-86-2 acetophenone 
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• 42052-52-8 1-hydroxy-4,4-dimethyl-1-phenylpentan-3-one 
• 13988-67-5 benzoylpivaloylmethane 
• 100-52-7 benzaldehyde 
• 75-97-8 3,3-dimethyl-butan-2-one 
• 538-44-3 4,4-dimethyl-1-phenyl-1-penten-3-one 

Relevant academic research and scientific papers

Albumin-directed stereoselective reduction of 1,3-diketones and β-hydroxyketones to anti diols

The reduction of 1,3-diketones and β-hydroxyketones with NaBH 4 in aqueous acetonitrile is highly stereoselective in the presence of stoichiometric amounts of bovine or human albumin, giving anti 1,3-diols with d.e. up to 96%. The same reaction, without albumin, gives syn and anti 1,3-diols in approximately 1:1 ratio. The presence of an aromatic carbonyl group is essential for diastereoselectivity in the NaBH4/albumin reduction of both 1,3-diketones and β-hydroxyketones. Thus, 3-hydroxy-1-(p-tolyl)-1- butanone is stereoselectively reduced in the presence of albumin, while reduction of its isomer 4-(p-tolyl)-4-hydroxy-2-butanone is not stereoselective. The albumin-controlled reduction is not stereospecific as both enantiomers of 1-aryl-3-hydroxy-1-butanones are reduced to diols with identical stereoselectivities. Circular dichroism of the bound substrates confirms that aromatic ketones are recognized by the protein's IIA binding site. Binding studies also suggest that 1,3-diketones are recognized in their enol form. From the effect of pH on binding of a diketone it is concluded that, in the complex with the substrate, ionizable residues His242 and Lys199 are in the neutral and protonated forms, respectively. A homology model of BSA was obtained and docking of model substrates confirms the preference of the protein for aromatic ketones. Modelling of the complexes with the substrates also allows us to propose a mechanism for the reduction of 1,3-diketones in which the chemoselective reduction of the first (aliphatic) carbonyl is followed by the diastereoselective reduction of the second (aromatic) carbonyl. The role of albumin is thus a combination of chemo- and stereocontrol.

Reduction of β-hydroxyketones by Sml2/H2O/ Et3N

(Chemical Equation Presented) Reduction of a series of β- hydroxyketones by Sml2/H2O/Et3N provided 1,3-diols in quantitative yields. The reactions were exceedingly clean with no byproduct formation, negating the need for f

Solvent-dependent diastereoselectivities in reductions of β-hydroxyketones by Sml2

The reductions of a series of β-hydroxyketones by Sml2 were examined in THF, DME, and CH3CN using methanol as a proton source. Reductions in THF and DME typically lead to the syn diastereomer with DME providing higher diastereoselect

Albumin-controlled stereoselective reduction of 1,3-diketones to anti-diols

An unprecedented combination of high chemo- and stereoselectivity in the NaBH4 reduction of 1:1 complexes between albumin and aromatic 1,3-diketones results in the formation of anti 1,3-diols with de up to 96%.

Functionalized organolithium compounds of DTBB-catalyzed sulfur-lithium exchange

The successive reaction of β- or γ-hydroxy or amino phenyl thioethers (1,4) with butyllithium and an excess of lithium powder in the presence of a catalytic amount of DTBB in THF at - 78°C leads to the formation of the corresponding β- or γ-functionalized organolithium compounds 2 or 5, respectively, which by treatment with different electrophiles [D2O, t- BuCHO, PhCHO, Me2CO, (CH2)4CO, (CH2)5CO] at temperatures ranging between - 78°C and room temperature yields, after hydrolysis with water, the expected functionalized alcohols or amines 3 or 6, respectively, in a completely regioselective manner.

β-Functionalised organolithium compounds through a sulfur-lithium exchange

The successive reaction of different β-hydroxy or β-amino tbioethers 1a-d with n-butyl-lithium and an excess of lithium powder and a catalytic amount of DTB in THF at -78°C leads to the formation of the corresponding β-functionalised organolithium compounds 2a-d, which by reaction with several electrophiles [D2O, Bu(t)CHO, PhCHO, Me2CO, (CH2)5CO] at temperatures ranging between -78 and 20°C yields, after hydrolysis with water, the expected functionalised alcohols or amines 3aa-de in a regioselective manner.

An Internally Activated Tin Hydride with Enhanced Reducing Ability

Tin hydride 1 is activated for nucleophilic hydride transfer and also for radical chain reduction, depending on solvent.The nucleophilic hydride pathway is favored in methanol, and 1 can be used as a selective reducing agent for ketones.Simple ketones are not reduced in aprotic solvents, but β-hydroxy ketones are activated internally by the hydroxyl group and can be reduced in THF with good control of stereochemistry, as in the conversion from 7 to 9 (30:1 9:8).A catalytic version of the nucleophilic hydride reductions in methanol has been developed using PhSiH3 as the stoichiometric hydride source.Radical chain dehalogenations can also be achieved with 1 at room temperature and without added radical initiators.Simple xanthates are not reduced efficiently in the absence of an initiator, but the reaction proceeds in the presence of AIBN.

Chiral Organosilicon Compounds in Asymmetric Synthesis of Chiral 1,3-Diols

Chiral 1,3-diols can be prepared in high enantiomeric purity (>99percent ee) from the reactions of the chiral silylcarbanion 2 with epoxides followed by oxidative cleavage of the carbon-silicon bond with hydrogen peroxide.The absolute configurations of so

STUDIES ON THE DIASTEREOSELECTIVE REDUCTION OF β-HYDROXY KETONES TO 1,3-DIOLS WITH COMMON HYDRIDE REAGENTS

Some common reducing agents were employed in the diastereoselective reduction of several β-hydroxy ketones to their corresponding syn-1,3-diols.The use of NaBH4 with a Ti(IV) chelating species produced syn diols with a moderate to good selectivity significantly depending upon the reaction conditions chosen (solvent, temperature, nature of the titanium species).The use of LiAlH4 at low temperature, in the presence of LiI, showed a high selectivity for reduction to syn diols, thus demonstrating a possible chelating role of lithium.Some interesting preliminary results have been also obtained in the diastereoselective reduction of MEM-protected β-alkoxy ketones.