65651-63-0

Usage

Uses

Used in the Food Industry:
(S)-4-Hydroxy-5-methyl-2-hexanone is used as a flavoring agent for its distinctive sweet, fruity aroma, enhancing the taste and appeal of various food products.
Used in the Perfume Industry:
In the perfume industry, (S)-4-Hydroxy-5-methyl-2-hexanone serves as a fragrance component, leveraging its sweet, fruity scent to contribute to the creation of various perfume blends.
Used in Pharmaceutical Production:
(S)-4-Hydroxy-5-methyl-2-hexanone is utilized in the production of pharmaceuticals, acting as a key intermediate in the synthesis of various medicinal compounds.
Used in the Synthesis of Organic Compounds:
(S)-4-Hydroxy-5-methyl-2-hexanone also finds application in the synthesis of other organic compounds, highlighting its versatility as a building block in organic chemistry.

InChI:InChI=1/C7H14O2/c1-5(2)7(9)4-6(3)8/h5,7,9H,4H2,1-3H3/t7-/m0/s1

Upstream product

• 78-84-2 isobutyraldehyde 
• 67-64-1 acetone 
• 123-42-2 4-Hydroxy-4-methyl-2-pentanone 
• 14035-54-2 1,1-diphenyl-1-hydroxy-3-butanone 
• 1669-43-8 (E)-4-isopropylbut-3-en-2-one 
• 875431-23-5 (3S,4R)-3,4-dihydroxy-5-methylhexan-2-one 
• 875431-29-1 1-((4S,5R)-5-Isopropyl-2,2-dimethyl-[1,3]dioxolan-4-yl)-ethanone 
• 97169-20-5 N,N-Dimethyl-N'-[1-methyl-2-((R)-toluene-4-sulfinyl)-eth-(E)-ylidene]-hydrazine 
• 123-75-1 pyrrolidine 

Downstream Products

• 28332-44-7 5-methylhex-4-en-2-one 
• 5166-53-0 5-methyl-3-hexene-2-one 
• 1669-43-8 (E)-4-isopropylbut-3-en-2-one 
• 1669-43-8 5-methyl-hex-3c-en-2-one 
• 59697-04-0 5-methyl-4-(toluene-4-sulfonyloxy)-hexan-2-one 
• 138101-91-4 (2S,4S)-2,4-Dihydroxy-2,5-dimethyl-hexanenitrile 
• 138101-91-4 (2S,4R)-2,4-Dihydroxy-2,5-dimethyl-hexanenitrile 
• 105627-15-4 5-methyl-4-di-isopropylsilyloxyhexan-2-one 
• 36402-53-6 (2RS,4SR)-5-methylhexane-2,4-diol 
• 36402-53-6 (2RS,4RS)-5-methylhexane-2,4-diol 
• 7732-18-5 water 
• 676165-04-1 (R)-4-(tert-butyldiphenylsiloxy)-5-methylhexan-2-one 
• 625-27-4 2-methyl-2-pentene 

Relevant academic research and scientific papers

Combining prolinamides with 2-pyrrolidinone: Novel organocatalysts for the asymmetric aldol reaction

Peptides and especially prolinamides have been identified as excellent organocatalysts for the aldol reaction. The combination of prolinamides with derivatives bearing the 2-pyrrolidinone scaffold, deriving from pyroglutamic acid, led to the identification of novel organocatalysts for the intermolecular asymmetric aldol reaction. The new hybrids were tested both in organic and aqueous media. Among the compounds tested, 22 afforded the best results in petroleum ether, while 25 afforded the products in brine in high yields and selectivities. Then, various ketones and aldehydes were utilized and the products of the aldol reaction were obtained in high yields (up to 100%) with excellent diastereo- (up to 97:3 dr) and enantioselectivities (up to 99% ee).

Tuning the sense of product stereochemistry in aldol reactions of acetone and aromatic aldehydes in the presence of water with a single chiral catalyst

We report the aldol addition of acetone to aromatic aldehydes in the presence of a large amount of water where the stereochemical outcome of the reactions can be tuned with achiral salt additives using a single proline-derived catalyst. Depending on the nature of the added salt the (R) and (S) enriched products could be obtained. In the reaction of 2-nitrobenzaldehyde with acetone, NaOAc promoted the formation of the (S)-enantiomer (20% ee) while using NH4Cl the (R)-enantiomer was obtained in excess (58% ee). A similar inversion was observed for several other aromatic aldehydes.

The 4,5-methano-l-proline as a chiral organocatalysts in direct asymmetric aldol reactions

The 4,5-methano-l-proline was studied for the direct asymmetric aldol reaction of acetone or cyclohexanone with various aromatic and aliphaticaldehydes at -20 °C or 0 °C. A loading of only 5mol % of derivative 1a was employed in this catalytic system, and excellent enantioselectivities (up to 99% ee) and yields (up to 98% yield) could be achieved.

Highly enantioselective direct asymmetric aldol reaction catalyzed by 4,5-methano-L-proline

The 4,5-methano-L-proline was used as chiral organocatalysts in direct asymmetric aldol reactions. Under the optimal conditions, excellent enantioselectivities (up to 99% ee) were obtained with high chemical yields (up to 95%) for a series of aldehydes using only 5 mol% catalyst loading. To show the practicality of the method, the reaction was tested at a large scale. The reaction was complete in 16 h, and the aldol product was obtained in 86% yield and 93% ee.

Synthesis of sulphur-modified bifunctional hydrotalcites and study of their surface characteristics by inverse gas chromatography

In this study, various sulphur-modified hydrotalcite catalysts were prepared, and the influence of calcination temperature on their acid-base properties was investigated. Structural characterization of the catalysts was studied using X-ray powder diffraction, scanning electron microscopy, N2 physisorption, elemental analysis and Fourier transform infrared spectroscopy. The structural characterization indicated that the layer structure of all catalysts was retained but the specific surface areas were enlarged. Inverse gas chromatography was carried out to quantitatively determine the catalysts' acid-base properties by calculating the thermodynamic parameters, including dispersive surface free energy, adsorption free energy, adsorption enthalpy, and acid-base interaction constants. The results showed that the strength and content of acidic and alkaline sites were enhanced with increasing calcination temperature. Moreover, several typical aldol condensation reactions were selected to study the catalytic activity of the developed catalysts. The results showed that the sulphur-modified hydrotalcite catalysts possess high activity and good regenerability for typical aldol condensation reactions.

Asymmetric Catalysis with Ethylene. Synthesis of Functionalized Chiral Enolates

Trialkylsilyl enol ethers are versatile intermediates often used as enolate surrogates for the synthesis of carbonyl compounds. Yet there are no reports of broadly applicable, catalytic methods for the synthesis of chiral silyl enol ethers carrying latent functionalities useful for synthetic operations beyond the many possible reactions of the silyl enol ether moiety itself. Here we report a general procedure for highly catalytic (substrate:catalyst ratio up to 1000:1) and enantioselective (92% to 98% major enantiomer) synthesis of such compounds bearing a vinyl group at a chiral carbon at the β-position. The reactions, run under ambient conditions, use trialkylsiloxy-1,3-dienes and ethylene (1 atm) as precursors and readily available (bis-phosphine)-cobalt(II) complexes as catalysts. The silyl enolates can be readily converted into novel enantiopure vinyl triflates, a class of highly versatile cross-coupling reagents, enabling the syntheses of other enantiomerically pure, stereodefined trisubstituted alkene intermediates not easily accessible by current methods. Examples of Kumada, Stille, and Suzuki coupling reactions are illustrated.

Unusual enantioselectivities in heterogeneous organocatalyzed reactions: Reversal of direction using proline di- versus tri-peptides in the aldol addition

The heterogeneous asymmetric direct aldol reactions between aldehydes (2-nitrobenzaldehyde, 2-methylpropanal) and ketones (acetone, cyclohexanone) in the presence of polystyrene (PS) resin supported di- and tripeptides were studied under otherwise identic

Improved conditions for the proline-catalyzed aldol reaction of acetone with aliphatic aldehydes

The proline-catalyzed asymmetric aldol reaction between aliphatic aldehydes and acetone has, to date, remained underdeveloped. Challenges in controlling this reaction include avoiding undesired side reactions such as aldol condensation and self-aldolization. In recent years we have developed optimized conditions, which enable high yields and good to excellent enantioselectivities, and which are presented in this communication. Georg Thieme Verlag Stuttgart New York.

Reversal of enantioselectivity in aldol reaction: New data on proline/λ-alumina organic-inorganic hybrid catalysts

We report new results on the aldol reactions between aldehydes of three different types (aromatic, aliphatic and cycloaliphatic) and acetone/cycloalkanones as reaction partners, driven by organic-inorganic hybrid catalyst Pro/λ-Al2O3. In contrast to the homogeneous liquidphase reaction, over Pro/λ-Al2O 3reversal of the enantioselection in up to 20-40 % ee depending on the structure of the aldehyde was observed in reactions of acetone. Reversal of the ee in the presence of c-Al2O3cannot be generalized, as it has only been observed for acetone among the ketones studied by us. It was proven using methods of a great variety such as ultrasonic irradiation, reuse measurements on used catalyst and the filtrate of the first reaction, measurements on the L-Pro-L-Pro(OH) dipeptide, studies using mixtures of L-Pro and D-Pro that the organic-inorganic hybrid catalyst Pro/λ-Al 2O3formed in situ is responsible for reversal of the ee. In the reactions of cycloalkanones there is presumably competition between the liquid-phase and the surface reaction over Pro/ c-Al2O 3with preference for the former. Based on these results a surface reaction pathway was proposed. Although, the ees obtained under heterogeneous catalytic conditions are low, further studies may lead to application of this unusual phenomenon for obtaining chiral heterogeneous catalysts suitable for the preparation of the desired enantiomer of a chiral compound using the same chiral source. Springer Science+Business Media New York 2013.

Reversal of the enantioselectivity in aldol addition over immobilized di- and tripeptides: Studies under continuous flow conditions

Heterogeneous asymmetric direct aldol reactions between aldehydes (2-nitrobenzaldehyde, 2-methylpropanal) and acetone catalyzed by polystyrene resin (PS) supported di- and tripeptides H-Pro-Pro-, H-Pro-Pro-Pro-, H-Pro-Glu(OH)-, H-Pro-Pro-Glu(OH)-, H-Pro-Asp(OH)-, H-Pro-Pro-Asp(OH)-, H-Ser-Glu(OH)-, H-Ser-Ser-Glu(OH)-, H-Val-Glu(OH)-, H-Val-Val-Glu(OH)-MBHA-PS, were studied under identical experimental conditions at room temperature in a continuous-flow fixed-bed reactor (CFBR) system. In the asymmetric aldol reactions reversal of enantioselectivity was observed on H-Pro-Pro-Glu(OH)- and H-Pro-Pro-Asp(OH)-MBHA-PS-supported catalysts (ee 42-67% S) as compared to the H-Pro-Glu(OH)- and H-Pro-Asp(OH)-MBHA-PS-supported catalyst (ee 28-82% R). In the case of H-Pro-Pro- and H-Pro-Pro-Pro-MBHA-PS-supported catalysts reversed enantioselectivity was observed by using the benzoic acid additive (12% S) as compared to the H-Pro-MBHA-PS catalyst (25% R). The stability of the catalysts in the flow system was consistent with the heterogeneous character of the reaction, as was the linear behavior obtained using mixtures of l- and d-enantiomers of the supported H-Pro-MBHA-PS catalyst. The enamine character of the reaction intermediates was supported by ESI-MS measurements. Based on these and the computed structure of the peptides, the conformation of the intermediate adducts is held responsible for chiral induction, therefore for the enantioselectivity inversion observed in these reactions.