108-10-1

Basic information

• Product Name: 4-Methyl-2-pentanone
• Synonyms: 2-Methyl-4-pentanal;2-Methyl-4-Pentanone;2-Methylpropyl methyl ketone;2-methylpropylmethylketone;2-Pentanone, 4-methyl-;2-Pentanone,4-methyl-;2-pentanone,-methyl-;4-Keto-2-methylpentane
• CAS NO: 108-10-1
• Molecular Formula: C₆H₁₂O
• Molecular Weight: 100.16
• EINECS: 203-550-1
• Product Categories: ketone;Amber Glass Bottles;Analytical Reagents;Analytical/Chromatography;CHROMASOLV for HPLC;Chromatography Reagents &HPLC &HPLC Grade Solvents (CHROMASOLV);HPLC/UHPLC Solvents (CHROMASOLV);Solvent Bottles;Solvent by Application;Solvent Packaging Options;Solvents;UHPLC Solvents (CHROMASOLV);ACS and Reagent Grade Solvents;Carbon Steel Cans with NPT Threads;Nutrition Research;Phytochemicals by Plant (Food/Spice/Herb);ReagentPlus;ReagentPlus Solvent Grade Products;Semi-Bulk Solvents;Zingiber officinale (Ginger)
• Mol File: 108-10-1.mol
• Article Data: 253

Chemical Properties

• Melting Point: -84 °C
• Boiling Point: 117-118 °C
• Flash Point: 56 °F
• Appearance: APHA: ≤15/Liquid
• Density: 0.801 g/mL at 25 °C(lit.)
• Vapor Density: 3.5 (vs air)
• Vapor Pressure: 15 mm Hg ( 20 °C)
• Refractive Index: n20/D 1.395(lit.)
• Storage Temp.: 2-8°C
• Solubility: water: soluble20g/L
• Explosive Limit: 1.2-8%, 93°F
• Water Solubility: 17 g/L (20 ºC)
• Merck: 14,5207
• BRN: 605399
• CAS DataBase Reference: 4-Methyl-2-pentanone(CAS DataBase Reference)
• NIST Chemistry Reference: 4-Methyl-2-pentanone(108-10-1)
• EPA Substance Registry System: 4-Methyl-2-pentanone(108-10-1)

Safety Data

• Hazard Codes: F,Xn,T
• Statements: 11-20-36/37-66-39/23/24/25-23/24/25
• Safety Statements: 9-16-29-45-36/37-7
• RIDADR: UN 1245 3/PG 2
• WGK Germany: 1
• RTECS: SA9275000
• TSCA: Yes
• HazardClass: 3
• PackingGroup: II
• Hazardous Substances Data: 108-10-1(Hazardous Substances Data)

Usage

Description

4-Methyl-2-pentanone has a pleasant odor. May be prepared by hydrogenation of mesityl oxide over Ni at 160 - 190°C; also by oxidation of methyl isobutyl carbinol.

Chemical Properties

Different sources of media describe the Chemical Properties of 108-10-1 differently. You can refer to the following data:
1. 4-Methyl-2-pentanone has a fruity, ethereal, spicy (on dilution) odor.
2. 4-Methyl-2-pentanone, also known as Methyl isobutyl ketone (MIBK), is a colorless liquid with a pleasant, sweet, fruity odor. The odor threshold can be as low as 0.10 ppm. It is 2% soluble in water by weight and with several other organic solvents. The lower explosive limit is 1.2% and the upper explosive limit is 8.0% at 200 °F. Methyl isobutyl ketone may be incompatible with strong oxidizers and potassium tert-butoxide.

Physical properties

Clear, colorless, watery liquid with a mild, pleasant odor. Odor threshold concentration is 47 ppbv (Leonardos et al., 1969). Experimentally determined detection and recognition odor threshold concentrations were 400 μg/m3 (100 ppbv) and 1.1 mg/m3 (270 ppbv), respectively (Hellman and Small, 1974).

Occurrence

Reported found in orange and lemon juice, grape; vinegar, baked potato, papaya, ginger, wheat bread, cheeses, milk, cooked egg, roast chicken, cooked beef, lamb fat, pork liver, hop oil, beer, cognac, coffee, tea, plumcot, plum brandy, mushroom, trassi, sesame seed, buckwheat, wort, elder flower, Bourbon vanilla, clary and red sage, crab, clam and Chinese quince.

Uses

Different sources of media describe the Uses of 108-10-1 differently. You can refer to the following data:
1. MIBK is used as a solvent for gums, resins,nitrocellulose and cellulose ethers, and various fats, oils, and waxes.
2. In paints, glues, and cleaning agents; used in the plastic and petrol industries
3. Methyl isobutyl ketone (hexone, isobutyl methyl ketone, 4-methyl-2-pentanone) is an organic solvent similar in structure and use to methyl butyl ketone. In addition to its use as a solvent for paints, lacquers, and varnishes, methyl isobutyl ketone is used in extraction processes and as a denaturant for rubbing alcohol. Methyl isobutyl ketone is also used as a synthetic flavoring in some varieties of rum, candy, and cheese. Unlike methyl butyl ketone, methyl isobutyl ketone has not been found to occur naturally.

Preparation

By hydrogenation of mesityl oxide over Ni at 160 to 190°C; also by oxidation of methyl isobutyl carbinol.

Production Methods

Methyl isobutyl ketone can be manufactured by two processes . The first is a mixed ketone process where MiBK, diisobutyl ketone, and acetone are coproduced in a single reaction using isopropanol as a starting material. The second method is used to produce the majority of MiBK and involves a three-step reaction sequence in which diacetone alcohol and mesityl oxide are formed as intermediates.

Aroma threshold values

Detection: 240 to 640 ppb

Taste threshold values

Taste characteristics at 25 ppm: sweet, ethereal, banana and fruity with dairy nuances

Synthesis Reference(s)

Journal of the American Chemical Society, 100, p. 5437, 1978 DOI: 10.1021/ja00485a031Tetrahedron Letters, 36, p. 2285, 1995 DOI: 10.1016/0040-4039(95)00191-ETetrahedron, 37, p. 3073, 1981 DOI: 10.1016/S0040-4020(01)98839-8

General Description

A clear colorless liquid with a pleasant odor. Flash point 73°F. Less dense than water. Vapors heavier than air.

Air & Water Reactions

Highly flammable. 4-Methyl-2-pentanone is sensitive to air (may form explosive peroxides). Slightly soluble in water.

Reactivity Profile

4-Methyl-2-pentanone is incompatible with caustic soda and other strong alkalis, hydrochloric acid, sulfuric acid and other strong inorganic acids, amines and oxidizing agents such as hydrogen peroxide, nitric acid, perchloric acid and chromium trioxide. 4-Methyl-2-pentanone reacts violently with potassium tert-butoxide. 4-Methyl-2-pentanone reacts vigorously with reducing materials. .

Hazard

Flammable, dangerous fire risk, explosivelimits in air 1.4–7.5%. Avoid ingestion and inhala-tion. Upper respiratory tract irritant, dizziness, andheadache. Possible carcinogen.

Health Hazard

Different sources of media describe the Health Hazard of 108-10-1 differently. You can refer to the following data:
1. Vapor causes irritation of eyes and nose; high concentrations cause anesthesia and depression. Liquid dries out skin and may cause dermatitis; irritates eyes but does not injure them.
2. MIBK exhibits low to moderate toxicity.It is more toxic than acetone. Exposureto 200 ppm can cause irritation of theeyes, mucous membranes, and skin. Prolonged skin contact can leach out fat fromthe skin. Exposure to high concentrationscan cause nausea, headache, and narcosis. Animal studies indicate that this compound could probably cause kidney damage,with symptoms of a heavier kidney, higherkidney-to-body weight ratio, and tubularnecrosis. An increase in liver weight wasnoted, too, associated with its exposure inanimal subjects. In male rats the effect wasobserved at 2000 ppm on 2 weeks’ exposure(6 hours/day) (Phillips et al. 1987). Otherthan for the male rat kidney effect, the levelsup to 1000 ppm for 14 weeks had no significant toxicological effect. In another study,exposure to 3000 ppm in rats and mice wasfound to cause increased liver and kidneyweights, decrease in food consumption, incidence of dead fetuses, and reduced fetal bodyweight (Tyl et al. 1987).Ingestion of MIBK can result in narcosis and coma. A genetic toxicology studyof MIBK showed a negative response inthe bacterial mutation assays and the yeastmitotic gene conversion assay (Brooks et al.1988).LD50 value, oral (rat): 2080 mg/kgLD50 value, intraperitoneal (rat): 400 mg/kg.

Flammability and Explosibility

Highlyflammable

Chemical Reactivity

Reactivity with Water No reaction; Reactivity with Common Materials: No reaction; Stability During Transport: Stable; Neutralizing Agents for Acids and Caustics: Not pertinent; Polymerization: Not pertinent; Inhibitor of Polymerization: Not pertinent.

Potential Exposure

MIBK is used as a solvent; a denaturant; and as an extractant; in the manufacture of methyl amyl alcohol; as a solvent in paints, varnishes, and lacquers; as an alcohol denaturant; as a solvent in uranium extraction from fission products.

Carcinogenicity

The National Toxicology Program conducted cancer bioassays by exposing groups of 50 male and 50 female F344 rats and B6C3F1 mice to MiBK vapor at 0, 450, 900, or 1800 ppm 6h/day, 5 days/ week for 2 years. Survival and body weight gain were decreased in male rats at 1800 ppm. Body weight gain was also decreased in male rats at 900 and in female mice at 1800ppm. A higher incidence of mineralization of the renal papilla was observed in male rats at all MiBK exposure levels. Chronic progressive nephropathy (CPN) and the incidences of adenoma and adenoma or carcinoma (combined) were increased for the male 1800 ppm exposure group. The severity of CPN and renal tubular hyperplasia was increased in all male rat exposure groups. An uncertain increase in mononuclear cell leukemia, adrenal medulla hyperplasia, and a positive trend for increases in benign or malignant pheochromocytomas (combined) were reported for the 1800 ppm male group. The NTP considered that there was some evidence of carcinogenic activity in male rats based on increased incidences of renal tubule neoplasms. None of the rodent bioassay results were considered clear evidence of carcinogenicity by NTP.

Environmental fate

Biological. Bridié et al. (1979) reported BOD and COD values of 2.06 and 2.16 g/g using filtered effluent from a biological sanitary waste treatment plant. These values were determined using a standard dilution method at 20 °C and stirred for a period of 5 d. Heukelekian and Rand (1955) reported a 5-d BOD value of 1.51 g/g which is 55.5% of the ThOD value of 2.72 g/g. Photolytic. When synthetic air containing gaseous nitrous acid and 4-methyl-2-pentanone was exposed to artificial sunlight (λ = 300–450 nm), photooxidation products identified were acetone, peroxyacetal nitrate, and methyl nitrate (Cox et al., 1980). In a subsequent experiment, the OHinitiated photooxidation of 4-methyl-2-pentanone in a smog chamber produced acetone (90% yield) and peroxyacetal nitrate (Cox et al., 1981). Irradiation at 3130 ? resulted in the formation of acetone, propyldiene, and free radicals (Calvert and Pitts, 1966). Second-order photooxidation rate constants for the reaction of 4-methyl-2-butanone and OH radicals in the atmosphere are 1.4 x 10-10, 1.42 x 10-10, and 1.32 x 10-10 cm3/molecule?sec at 295, 299, and 300 K, respectively (Atkinson, 1985). The atmospheric lifetime was estimated to be 1–5 d (Kelly et al., 1994). Photolytic. Cox et al. (1980) reported a rate constant of 1.24 x 10-11 cm3/molecule?sec for the reaction of gaseous 4-methyl-2-pentanone with OH radicals based on a value of 8 x 10-12 cm3/molecule?sec for the reaction of ethylene with OH radicals. Chemical/Physical. 4-Methyl-2-pentanone will not hydrolyze in water because it does not contain a hydrolyzable functional group (Kollig, 1993).

Shipping

UN1245 Methyl isobutyl ketone, Hazard Class: 3; Labels: 3-Flammable liquid.

Purification Methods

Reflux the ketone with a little KMnO4, wash it with aqueous NaHCO3, dry with CaSO4 and distil it. Acidic impurities are removed by passage through a small column of activated alumina. [Beilstein 1 IV 3305.]

Incompatibilities

Able to form unstable and explosive peroxides on contact with air. Reacts violently with strong oxidizers, potassium tert-butoxide; strong acids; aliphatic amines; reducing agents

Waste Disposal

Consult with environmental regulatory agencies for guidance on acceptable disposal practices. Generators of waste containing this contaminant (≥100 kg/mo) must conform to EPA regulations governing storage, transportation, treatment, and waste disposal. Incineration.

InChI:InChI=1/C6H12O/c1-5(2)4-6(3)7/h5H,4H2,1-3H3

Upstream product

• 186581-53-3 diazomethane 
• 590-86-3 isovaleraldehyde 
• 67-56-1 methanol 
• 19860-68-5 2-methyl-6-methylene-7-octene-4-one 
• 108-11-2 Methyl isobutyl carbinol 
• 56-23-5 tetrachloromethane 
• 3002-23-1 6-methylheptan-2,4-dione 
• 917-64-6 methyl magnesium iodide 
• 625-28-5 Isovaleronitrile 
• 141-79-7 4-methyl-pent-3-en-2-one 
• 625-33-2 3-penten-2-one 
• 75-16-1 methylmagnesium bromide 
• 64-17-5 ethanol 
• 123-51-3 i-Amyl alcohol 

Downstream Products

• 4196-96-7 (E)-1-(furan-2-yl)-5-methylhex-1-en-3-one 
• 56750-95-9 1t-benzo[1,3]dioxol-5-yl-5-methyl-hex-1-en-3-one 
• 3002-23-1 6-methylheptan-2,4-dione 
• 1540-38-1 3-(1-methylethyl)pentane-2,4-dione 
• 76216-40-5 3-isopropyl-pentane-2,4-dione (E)-enol tautomer 
• 82297-68-5 (E)-1-(4-methoxyphenyl)-5-methylhex-1-en-3-one 
• 83092-98-2 (E)-1-(4-hydroxy-3-methoxyphenyl)-5-methylhex-1-en-3-one 
• 54596-70-2 2-(1,3-dimethyl-butylamino)-ethanol 
• 2035-08-7 4-methyl-2-pentanone ethylene acetal 
• 98489-37-3 4-isobutyl-pyrimidine 
• 6668-06-0 2-cyano-3,5-dimethyl-hex-2-enoic acid methyl ester 
• 14368-39-9 3,5-dimethyl-hex-2-enenitrile 
• 22703-72-6 1,1,1-Trichlor-2-hydroxy-6-methyl-4-heptanon 
• 32189-75-6 2,4-dimethyl-6-hepten-4-ol 

Relevant articles and documents

Palladium catalyzed mild reduction of α,β-unsaturated compounds by triethylsilane

The palladium(II) chloride/triethylsilane system has been successfully applied for the selective hydrogenation of the carbon-carbon double bond of α,β-unsaturated ketones to yield the corresponding saturated carbonyl compounds. The reaction takes place under mild conditions and affords high yields.

2-Phenylbenzothiazoline as a Reducing Agent in the Conjugate Reduction of α,β-Unsaturated Carbonyl Compounds

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Selective deoximation using alumina supported potassium permanganate

Ketoximes are converted to the parent ketones in good yields when treated with potassium permanganate supported on neutral alumina (ASPP). An optimized procedure has been developed, the simple work-up minimizes loss of product and oximes have been selectively oxidized in the presence of alkenes.

Alkoxy radical isomerization products from the gas-phase OH radical- initiated reactions of 2,4-dimethyl-2-pentanol and 3,5-dimethyl-3-hexanol

The products of the gas-phase reactions of the OH radical with 2,4- dimethyl-2-pentanol and 3,5-dimethyl-3-hexanol in the presence of NO(x) have been determined at atmospheric pressure of air and 296 ± 2 K to assess the occurrence and importance of alkoxy radical isomerization. The products identified and quantified and their formation yields were as follows: from 2,4-dimethyl-2-pentanol: acetone, 0.92 ± 0.15; 2-methylpropanal, 0.209 ± 0.022; 4-methyl-2-2-pentanone, 0.046 ± 0.008; and 4-hydroxy-4-methyl-2- pentanone, 0.116 ± 0.018; from 3,5-dimethyl-3-hexanol: acetone, 0.120 ± 0.029; 2-butanone, 0.275 ± 0.021; 2-methylpropanal, 0.169 ± 0.016; 4- methyl-2-pentanone, 0.161 ± 0.012; and 4-hydroxy-4-methyl-2-pentanone, 0.250 ± 0.023. The observed formation of 4-hydroxy-4-methyl-2-pentanone provides conclusive evidence for the occurrence of isomerization of the alkoxy radicals (CH3)2C(OH)CH2C(O)(CH3)2 and CH3CH2C(CH3)(OH)CH2C(O)(CH3)2 via 1,5-H shifts. The reaction mechanisms are discussed, and isomerization rate constants for 1,5-H-atom abstraction from the -CH3 and -CH2- groups in the RCH2C(CH3)(OH)- CH2C(O)(CH3)2 alkoxy radicals (R = H and CH3) are derived.

Ethanolic or aqueous formic acid (1:1) - A new efficient reagent for the regeneration of ketones from phenylhydrazones

50% Ethanolic or aqueous formic acid has been found to be extremely efficacious for the regeneration of aliphatic and aromatic ketones from phenylhydrazones.

Dehydration of 4-methylpentan-2-ol over lanthanum and cerium oxides

Lanthanum and cerium oxides have been tested for the title reaction at 623 K and atmospheric pressure in a flow reactor. Lanthanum oxide (prepared from the corresponding nitrate) gives mainly 4-methylpent-1-ene (80% of the products). Similar results are observed with cerium oxide obtained from the corresponding hydroxide, whereas cerium oxide prepared from nitrate is less selective towards alk-1-enes. In addition to dehydration, dehydrogenation to 4-methylpentan-2-one is also observed to a limited extent for all the catalysts. Information on the acid-base properties of the samples was obtained by adsorption microcalorimetry of ammonia and carbon dioxide and correlated to reaction selectivities. Possible changes in the oxidation state of cerium ions due to the reaction atmosphere are considered. The present results are compared with former data for zirconia catalysts. Modification of cerium oxide via immersion in NaOH solution does not appear to be useful for improving alk-1-ene selectivity.

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Effect of metal modification of titania and hydrogen co-feeding on the reaction pathways and catalytic stability in the acetone aldol condensation

A stable performance of TiO2 catalysts for gas-phase acetone aldol condensation was observed when reduced metals were added (Pt or Ni, 1.5 wt%) and the reactions were conducted in presence of hydrogen. In both cases, the resulting metal-loaded catalysts are stable for 10 h, whereas continuous deactivation is observed for the parent TiO2 catalyst (573 K). Both the activation of the H2 molecule by metal nanoparticles and the change of the catalytic surface by metal insertion (in the case of Ni-loaded catalyst) enable suppressing oligomerization (by hindering enolates formation) and the strong adsorption of intermediates (by decreasing the concentration of high-strength acid-basic active sites), respectively. More interestingly, these metals allow to tune the selectivity of the reaction. Indeed, the Ni-loaded titania catalyst is highly selective for the synthesis of α,β-unsaturated ketones (selectivity to unsaturated C6 and C9 species >98%, at ～12% acetone conversion), whereas the Pt-loaded one is highly selective to the formation of saturated C6 and C9 ketones (MIBK and DIBK, with selectivities >95% at ～42% acetone conversion). The catalytic activity and stability of the two materials (Ni/TiO2 and Pt/TiO2) in both absence and presence of H2 are compared between them and with those of the parent TiO2. The results obtained by the reaction gas-phase analysis are supplemented through different solid characterization techniques (i.e., CO2-TPD and NH3-TPD, HRTEM, XPS, TPO, and DRIFTS).

Regiospecific solvent-free transfer hydrogenation of α,β-unsaturated carbonyl compounds catalyzed by a cationic ruthenium(II) compound

[(PPh3)2Ru(CH3CN)3Cl][BPh4] has been found to catalyze the selective reduction of double bonds in α,β-unsaturated ketones with high conversions when formic acid is the hydrogen donor.

CONVERSION OF ALKANES BY THE ACTION OF ACYL HALIDES AND AlBr3 UNDER MILD CONDITIONS

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Intramolecular Activation of a N-Methyl C-H Bond by an Electron Rich Iridium Centre: a Novel Chemoselective Reduction Catalyst

The iridium complex > formed by intramolecular C-H oxidative addition, as shown by X-ray analysis, behaves as a chemoselective catalyst in hydrogen transfer reduction of α,β-unsaturated ketones to unsaturated alcohols.

The hydroxyl radical reaction rate constant and products of 3,5-dimethyl-1-hexyn-3-ol

A bimolecular rate constant, κDHO, of (29 ± 9) × 10-12 cm3 molecule-1 s-1 was measured using the relative rate technique for the reaction of the hydroxyl radical (OH) with 3,5-dimethyl-1-hexyn-3-ol (DHO, HC≡CC(OH)(CH3)CH2CH(CH3 2) at (297 ± 3) K and 1 atm total pressure. To more clearly define DHO's indoor environment degradation mechanism, the products of the DHO + OH reaction were also investigated. The positively identified DHO/OH reaction products were acetone ((CH3 2C=O), 3-butyne-2-one (3B2O, HC≡CC(=O)(CH3)), 2-methyl-propanal (2MP, H(O=)CCH(CH3)2), 4-methyl-2-pentanone (MIBK, CH3C(=O CH2 CH(CH3)2), ethanedial (GLY, HC(=O C(=O)H), 2-oxopropanal (MGLY, CH3C(=O)C(=O)H), and 2,3-butanedione (23BD, CH3C(=O)C(=O)CH3). The yields of 3B2O and MIBK from the DHO/OH reaction were (8.4 ± 0.3) and (26 ± 2)%, respectively. The use of derivatizing agents O-(2,3,4,5,6-pentalfluorobenzyl)hydroxylamine (PFBHA) and N,O-bis (trimethylsilyl)trifluoroacetamide (BSTFA) clearly indicated that several other reaction products were formed. The elucidation of these other reaction products was facilitated by mass spectrometry of the derivatized reaction products coupled with plausible DHO/OH reaction mechanisms based on previously published volatile organic compound/OH gas-phase reaction mechanisms.

One-step synthesis of methyl isobutyl ketone from acetone and hydrogen over Cu-on-MgO catalysts

The one-step synthesis of methyl isobutyl ketone (MIBK) from acetone and hydrogen over Cu-on-MgO catalysts was studied at atmospheric pressure in a fixed bed continuous flow reactor. Catalysts with various copper loadings were prepared by impregnation and coprecipitation and characterized by BET and Cu(O) surface area measurements, XRD, SAXS, thermal analysis, and basicity measurements. A 3.46% Cu-on-MgO prepared by coprecipitation, calcined at 723 K for 4 h, and pretreated in hydrogen (673 K, 1 h) showed high and stable activity and selectivity in the production of MIBK. Under the best conditions (553 K reaction temperature, 15% molar excess of hydrogen to acetone, and 1920 ml h-1 gcat-1 space velocity) MIBK is formed in 45-48% yield (60-80% conversion and 60-75% selectivity) over a period of 24 h-on-stream. The results of deuterium labeling studies point to metallic sites catalyzing deuterium exchange and basic sites catalyzing dimerization of acetone, leading eventually to MIBK with high deuterium content. A comparison of deuterium contents of acetone, mesityl oxide (MO), and MIBK shows that the surface deuterium pool is highly diluted with hydrogen, formed during the exchange process. Deuterium incorporation during the saturation of the carbon-carbon double bond of MO to form MIBK, therefore, is less than expected. Formation of diisobutyl ketone with very low deuterium content is suggested to result from the involvement of strongly bound surface intermediates with long residence time not allowing exchange process.

1,3-Dichloro-5,5-dimethylhydantoin (DCDMH) as a new oxidizing agent for the facile and selective oxidation of oximes to their carbonyl compounds

Oximes are converted to the parent carbonyl compounds in good yields when treated with 1,3-dichloro-5,5-dimethylhydantoin (DCDMH) (1). An optimized procedure has been developed; the simple work-up minimizes loss of product and oximes have been selectively oxidized in the presence of alcohols and alkenes.

Copper(I)-catalysed Conjugate Reduction of α,β-Unsaturated Carbonyl Compounds by Lithium Aluminium Hydride

CuI catalyses an efficient conjugate reduction of α,β-unsaturated carbonyl compounds by LiAlH4 in the presence of hexamethylphosphoric triamide at -78 degC.

Oxidative cleavage of oximes with silica-gel-supported chromic acid in nonaqueous media

A simple procedure for a clean and high-yielding oxidative deoximation of benzaldoximes and ketoximes using a silica-gel-supported chromic acid reagent has been developed. This solid-supported reagent allows us to carry out this reaction in nonaqueous dichloromethane reaction media. Copyright Taylor & Francis Group, LLC.

Catalytic synthesis of cumene from benzene and acetone

The reaction of benzene hydroalkylation with acetone on bifunctional catalysts has been studied and the principal features of the process have been revealed, wherein the catalysts contain a copper oxide-copper chromite binary system as a hydrogenating component and BEA, MOR, FAU, or MFI zeolite as an alkylating component. It has been found that the use of the catalyst based on the mixed copper-chromium oxide and mordenite, running the process at 150 C and 3 MPa, and feedstock dilution with benzene (C6H6: C 3H6O = 9: 1) facilitate increasing of the yield of cumene as a main product.

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Nickel catalyzed silane reductions of α, β - Unsaturated ketones and nitriles

Activated nickel, produced by the ultrasound-promoted reduction of nickel iodide with lithium, catalyzes the 1,4 addition of phenylsilane to α, β-unsaturated ketones and α, β-unsaturated nitriles to give, after hydrolysis, high yields of the products of 1, 2 hydrogenation.

Study on the selective hydrogenation of isophorone

3,3,5-Trimethylcyclohexanone (TMCH) is an important pharmaceutical intermediate and organic solvent, which has important industrial significance. The selective hydrogenation of isophorone was studied over noble metal (Pd/C, Pt/C, Ir/C, Ru/C, Pd/SiO2, Pt/SiO2, Ir/SiO2, Ru/SiO2), and non-noble metal (RANEY Ni, RANEY Co, RANEY Cu, RANEY Fe, Ni/SiO2, Co/SiO2, Cu/SiO2, Fe/SiO2) catalysts and using solvent-free and solvent based synthesis. The results show that the solvent has an important effect on the selectivity of TMCH. The selective hydrogenation of isophorone to TMCH can be influenced by the tetrahydrofuran solvent. The conversion of isophorone is 100%, and the yield of 3,3,5-trimethylcyclohexanone is 98.1% under RANEY Ni and THF. The method was applied to the selective hydrogenation of isopropylidene acetone, benzylidene acetone and 6-methyl-5-ene-2-heptanone. The structures of the hydrogenation product target (4-methylpentan-2-one, 4-benzylbutan-2-one and 6-methyl-heptane-2-one) were characterized using 1H-NMR and 13C-NMR. The yields of 4-methylpentan-2-one, 4-benzylbutan-2-one and 6-methyl-heptane-2-one were 97.2%, 98.5% and 98.2%, respectively. The production cost can be reduced by using RANEY metal instead of noble metal palladium. This method has good application prospects. This journal is

An exceptionally rapid and selective hydrogenation of 2-cyclohexen-1-one in supercritical carbon dioxide

Selective hydrogenation of 2-cyclohexen-1-one over Pt-MCM-41 proceeds at a very high rate and produces cyclohexanone with selectivity of 100% in a batch reactor; a marked increase in the reaction rate (TOF) from 2283 min-1 to 5051 min-1 is observed on increasing the pressure from 7 MPa to 14 MPa at 40°C. The Royal Society of Chemistry 2009.

Selective Catalytic Oxidation of Organic Compounds by Nitrogen Dioxide

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Merging N-Hydroxyphthalimide into Metal-Organic Frameworks for Highly Efficient and Environmentally Benign Aerobic Oxidation

Two highly efficient metal-organic framework catalysts TJU-68-NHPI and TJU-68-NDHPI have been successfully synthesized through solvothermal reactions of which the frameworks are merged with N-hydroxyphthalimide (NHPI) units, resulting in the decoration of pore surfaces with highly active nitroxyl catalytic sites. When t-butyl nitrite (TBN) is used as co-catalyst, the as-synthesized MOFs are demonstrated to be highly efficient and recyclable catalysts for a novel three-phase heterogeneous oxidation of activated C?H bond of primary and secondary alcohols, and benzyl compounds under mild conditions. Based on the high efficiency and selectivity, an environmentally benign system with good sustainability, mild conditions, simple work-up procedure has been established for practical oxidation of a wide range of substrates.

Chemoselective and Site-Selective Reductions Catalyzed by a Supramolecular Host and a Pyridine-Borane Cofactor

Supramolecular catalysts emulate the mechanism of enzymes to achieve large rate accelerations and precise selectivity under mild and aqueous conditions. While significant strides have been made in the supramolecular host-promoted synthesis of small molecules, applications of this reactivity to chemoselective and site-selective modification of complex biomolecules remain virtually unexplored. We report here a supramolecular system where coencapsulation of pyridine-borane with a variety of molecules including enones, ketones, aldehydes, oximes, hydrazones, and imines effects efficient reductions under basic aqueous conditions. Upon subjecting unprotected lysine to the host-mediated reductive amination conditions, we observed excellent ?-selectivity, indicating that differential guest binding within the same molecule is possible without sacrificing reactivity. Inspired by the post-translational modification of complex biomolecules by enzymatic systems, we then applied this supramolecular reaction to the site-selective labeling of a single lysine residue in an 11-amino acid peptide chain and human insulin.