Ketones, acetalization

Condensation. Depending on the reaction conditions, a variety of condensation products are obtained from the reaction of aromatic amines with aldehydes, ketones, acetals, and orthoformates. 

Azirines react with alcohols in the presence of alkoxides to give alkoxyaziridines (67JA4456). Further treatment with alcohol and alkoxide results in the formation of amino ketone acetals. Alkoxyaziridines are not isolated in general from the acid-catalyzed addition of methanol to azirines. Azirines are also known to react with amines (66JOC1423). Frequently the initially produced adducts undergo subsequent transformations. 

FIG. 15-42 Extraction in Mixco columns, methyl isobutyl ketone-acetic acid-water (continuous), d, = 0.5 ft, Zj = 0..3.3.3 ft, X = flooded condition. To convert feet to meters, multiply by 0..34S to convert feet per hour to meters per hour, multiply by 0.3048. 

FIG. 15 53 Effect of pulsing on extraction in a packed column methyl isobutyl ketone-acetic acid-water (continuous). Tower diameter = 1.58 in, 27-in depth of V4-in Raschig rings. = Vc = 7.5 to 10. To convert inches to centimeters, multiply by 2.54. [Data of Chanhy, von Berg, and Wiegandt, Ind. Eng. Chem., 47, 1153 (1.9.55), with permission. ... 

Note TLC was performed on silica gel, and the solvents were (1) -bntanol/glacial acetic acid/water (2 1 1, v/v), (IV) isoamyl alcohol/ethy methyl ketone/glacial acetic acid/water (40 40 7 13, v/v), (VII) n-bntanol/2-propanol/water/glacial acetic acid (30 50 10 2, v/v), (VIII) ethyl methyl ketone/acetic acid/methanol (3 1 1, v/v), and (IX) n-bntanol/benzyl alcohol/glacial acetic acid (8 4 3, v/v). 

Scheme 9.4. Reactions of Alkenyl and Allylic Silanes with Aldehydes, Ketones, Acetals,...

The reaction of silyl ketone acetals with imines under irradiation has been explored. The versatility of the microwave approach is illustrated in Scheme 8.45. 

The direct comparison of 1 and 2 in a variety of RCM reactions also indicates a presumably close relationship between these catalysts (Table 1) [6]. Both of them give ready access to cycloalkenes of almost any ring size > 5, including medium sized and macrocyclic products. Only in the case of the 10-membered jasmine ketolactone 16 was the yield obtained with 2a lower than that with lc this result may be due to a somewhat shorter lifetime of the cationic species in solution. However, the examples summarized in Table 1 demonstrate that the allenylidene species 2 exhibit a remarkable compatibility with polar functional groups in the substrates, including ethers, esters, amides, sulfonamides, ketones, acetals, glycosides and even free hydroxyl groups. 

Although the ruthenium allenylidene complexes 2 have not yet been as comprehensively studied as their carbene counterparts, they also seem to exhibit a closely related application profile [6]. So far, they have proven to tolerate ethers, esters, amides, sulfonamides, ketones, acetals, glycosides and free secondary hydroxyl groups in the substrates (Table 1). 

Methyl isovalerate, azeotropic mixtures with butyl alcohols, 4 395t Methyl ketones, acetic anhydride used in synthesis, 1 148 Methyllithium, 14 249 15 147 Methylmagnesium chloride, 16 319 (R)-(—)-Methylmandelic acid chloride, chiral derivatizing reagent, 6 76t Methyl mercaptan production, 15 17 3-Methylmercaptopropionaldehyde (MMP), intermediate in methionine synthesis, 1 268, 269, 276... 

Kekule structure org chem A molecular structure of a cyclic conjugated system that is depicted with alternating single and double bonds. ka-k3,la. strak-char j ketal oRG CHEM 1. Former term for the =CO group, as in dimethyl ketal (acetone). 2. Any of the ketone acetates from condensation of alkyl orthoformates with ketones in the presence of alcohols. ke,tal ... 

Oleic acid from oleic acid, linoleic acid Steam-treated silicalite Methyl ethyl ketone/ acetic aid [189]... 

Colorless gas pungent suffocating odor gas density 2.927 g/L at 20°C heavier than air, vapor density 2.263 (air=l) condenses to a colorless liquid at -10°C density of liquid SO2 1.434 g/mL freezes at -72.7°C critical temperature 157.65°C critical pressure 77.78 atm critical volume 122 cc/g dielectric constant 17.27 at -16.5°C dissolves in water forming sulfurous acid, solubility 22.97 g and 11.58 g/lOOmL water at 0° and 20°C, respectively, under atmospheric pressure very soluble in acetone, methyl isobutyl ketone, acetic acid, and alcohol soluble in sulfuric acid liquid SO2 slightly miscible in water. 

It has now been found that further extension of this reaction to ketone acetals and a wide range of aldehydes and ketones is possible when catalytic amounts of zinc chloride are added to the reaction mixture. The catalyzed reaction generally proceeds at room temperature and usually gives good yields of 2,2-alkoxyoxetanes (equation 100). This appears to be the method of choice for such compounds, since it is highly regiospecific, whereas the photochemical addition of aldehydes or ketones to ketene acetals is not (77JOC3128). 

CA 68, 41780b(1968) [Thickeners (such as homopolymers and copolymers of unsatd acids, ketones acetals) for liquid expls (such as NG) are discussed. For example, lOg of a 40% soln of poly(vinylacetate) in EtOAc was mixed with 90g NG and after evapn of EtOAc on a water baih, a clear, homogeneous viscous soln was formed. Condensation products of aldehydes and ketones and of diols and... 

Initiator systems used to initiate photopolymerization with UV light generate radicals mostly by homolytic dissociation. Ketone acetals (e.g., Irgacure 651) absorb in the mid-range UV, dissociating to a benzoyl radical which initiates acrylate polymerization. The benzoyl group remains as part of the formed polymer (Eqs. 14 and 15). 

Example Components Glycold Toluene Ketone Acetate... 

Efforts have also been made to utilize ketone acetals bearing a trichlorosilyl group as an enolate donor (Scheme 6.12) [63a]. This reaction led to optically active / -hydroxy carboxylic acid esters (S)-23 in good yields, although enantioselectivity remained modest only (ee values up to 50% ee when phosphoramide is used in... 

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