Methyl isopropyl ketone, reaction with

Carboxylic acids can also be formed by a reaction of small alkanes, carbon monoxide, and water on solid acid catalysts (93,94). By in situ C MAS NMR spectroscopy (93), the activation of propane and isobutane on acidic zeolite HZSM-5 was investigated in the presence of carbon monoxide and water. Propane was converted to isobutyric acid at 373 73 K, while isobutane was transformed into pivalic acid with a simultaneous production of hydrogen. On SZA, methyl isopropyl ketone was observed as evidence for the carbonylation of isobutane with carbon monoxide after the sample was held at 343 K for 1 h (94). When the reaction of isobutane and carbon monoxide was carried out in the presence of water, pivalic acid was identified as the main reaction product (94). These observations are rationalized by the existence of a small number of sites capable of generating carbenium ions, which can be further trapped by carbon monoxide (93). 

In a paper emphasizing the preparative value, Schulz and Kluge described the a-hydroxylation of ketones in good yields by using 2 equivalents of triarylarainium salts in moist acetonitrile [172]. In contrast to the oxidative functionalization of 68, 70 and 72 the reaction with cyclohexanone (64) and methyl isopropyl ketone (80) was run in the presence of a hindered pyridine base. Thus, mechanistically, it cannot rigorously be stated whether ends or the enolates are oxidized (cf Sect. 3.2). 

The reaction of isobutane with carbon monoxide in the presence of an excess of AICI3 was first reported by Nenitzescu et al. to yield a complex mixture of products, mainly carboxylic acids (Koch-Haaf reaction), but also some methyl isopropyl ketone, a formylation product. Later, Olah et al. louiid " that in the reaction of adamantane (26) with carbon monoxide under superacidic catalysis, formylation (formation of 1-adamantanecarboxaldehyde) effectively competes with Koch-Haaf carboxylation (formation of 1 -adamantanecarboxyUc acid). On the basis of results acquired by the reaction of 1,3,5,7-tetradeu-teroadamantane, formylation was interpreted by a-insertion of the formyl cation into the tertiary C-H bond [Eq. (6.47)]. 

The products of the photochemical reactions of aliphatic hydrocarbons in the presence of nitrogen oxides are reasonably well understood. For example, -butane is converted to CH2O, CH3CHO, and methyl ethyl ketone, together with the nitrogen-containing species methyl, ethyl and isopropyl nitrate (14-16) and perox-yacetyl nitrate ( PAN, 17 Altshuller et al., 1969). Radical (RO-, RC = 0 and ROO-) recombination reactions with NO2 probably account for the formation of... 

Catalyst 10 was introduced for reactions in aqueous systems in the presence of surfactant Brdnsted acids, and 13 promotes the aldol reaction in the presence of a base, whereas prolinamide 4, prepared by click stra-tegy, has been used for the first aldol reaction of thiazolecarbaldehyde with methyl-isopropyl ketone on water with excellent results. Phthalimido-prolinamide 12 is also effective in promoting aldol reactions in neat conditions. 

Ionic strength and specific ion effects have been investigated in the oxidation of mandelic acid by cerium(iv) sulphate. Unlike the reaction in HCIO4 where there is spectrophotometric and kinetic evidence for complex formation, under these conditions there is a first-order rate dependence of both oxidant and reductant. The replacement of H+ by Li+, Na+, or K+ produces only a minor change in rate and has no effect on the activation parameters. Rate laws which are essentially similar have been established in the reactions with cyclohexane-1,4-diol cyclopentanone, and methyl isopropyl ketone. The enol form of the substrate is favoured as the active reagent in the latter two reactions. 

The idea of kinetic versus thermodynamic control can be illustrated by discussing briefly the case of formation of enolate anions from unsymmetrical ketones. This is a very important case for synthesis and will be discussed more fully in Chapter 1 of Part B. Any ketone with more than one type of a-hydrogen can give rise to more than one enolate. Many studies have shown that the ratio of the possible enolates depends on the reaction conditions. This can be illustrated for the case of methyl isopropyl ketone (3-methyl-2-butanone). If the base chosen is a strong, sterically hindered one and the solvent is aprotic, the major enolate formed is 3. If a protic solvent is used or if a weaker base (one comparable in basicity to the ketone enolate) is used, the dominant enolate is 2. Enolate 3 is the kinetic enolate while 2 is the thermodynamically favored enolate. 

METHOD 4 [115]-80% phenol in aqueous H2SO4 soiution of pH 3 is brought to 50 C. 30% H2O2 is then added causing an exothermic reaction and a temperature of 15 C over 3-4 minutes time. 6% aqueous H2SO3 is added after 4.5 minutes, the solution quickly cooled and extracted with isopropyl acetone (Strike would think that another solvent like methyl ethyl ketone could be used) to give 60% catechol. 

Anhydrous stannous chloride, a water-soluble white soHd, is the most economical source of stannous tin and is especially important in redox and plating reactions. Preparation of the anhydrous salt may be by direct reaction of chlorine and molten tin, heating tin in hydrogen chloride gas, or reducing stannic chloride solution with tin metal, followed by dehydration. It is soluble in a number of organic solvents (g/100 g solvent at 23°C) acetone 42.7, ethyl alcohol 54.4, methyl isobutyl carbinol 10.45, isopropyl alcohol 9.61, methyl ethyl ketone 9.43 isoamyl acetate 3.76, diethyl ether 0.49, and mineral spirits 0.03 it is insoluble in petroleum naphtha and xylene (2). 

In an apparatus suitably protected against atmospheric moisture and fitted with a gas-inlet tube, mechanical stirrer, and an efficient reflux condenser, to a solution of 45 gm (0.45 mole) of ethyl isopropyl ketone and 5 gm of freshly distilled acetyl chloride is added, through the gas-inlet tube, 18 gm (0.24 mole) of ethyl nitrite at 45°-55°C over a 2 hr period. The reaction mixture is stored overnight in a refrigerator, whereupon 15.2 gm (48.7% based on ethyl nitrite used) of 2-methyl-2-nitroso-3-pentanone dimer (bimolecular ethyl a-nitroso-isopropyl ketone) deposits. The product is isolated by filtration, m.p. 122°-123°C. 

Michael additions of C-nudeophiles such as the indanone 1 have been the subject of numerous further studies For example, the reaction between the indanone 1 and methyl vinyl ketone was effected by a solid-phase-bound quinine derivative in 85% yield and with remarkable 87% ee by d Angelo, Cave et al. [5], Co-polymers of cinchona alkaloids with acrylonitrile effected the same transformation Kobaya-shi and Iwai [6a] achieved 92% yield and 42% ee and Oda et al. [6b] achieved almost quantitative yield and up to 65% ee. Similarly, partially resolved 2-(hydroxy-methyl)quinudidine was found to catalyze the reaction between 1 and acrolein and a-isopropyl acrolein with induction of asymmetry, but no enantiomeric excesses were determined [7]. As shown in Scheme 4.4, the indanone 7 could be added to MVK with up to 80% ee under phase-transfer conditions, by use of the Cinchona-derived PT-catalysts 9a and 9b, affording the Michael-product 8 or enf-8, respectively [8]. The adducts 8 or ent-8 were intermediates in the stereoselective Robinson anellation of a cydohexenone ring to the indanone 7 [8],... 

Fig (4) The transformation of the ketone (24) to the cyclic ether (9) applying the standard organic reactions is described It wa subjected to three sequencial reactions with reagents mentioned for the conversion to cyclic ether (30). Isopropylation and by aromatization, it produces the phenol (31), which is converted to pisiferol (4). This on subjection to oxidation, esterification and deoxygenation respectively, furnish O-methyl pisiferate (5) and this is easily converted to pisiferic acid (1). 

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