Combination tables ketones

Table 3.3-5 Result of one-pot preparation of optically active sec-alcohols 94a,b and 94e-i by a combination of ketone reduction and enantiomeric resolution in a water suspension medium.

To the synthetic chemist the most important of the reactions m Table 17 1 are the last two the oxidation of primary alcohols to aldehydes and secondary alcohols to ketones Indeed when combined with reactions that yield alcohols the oxidation methods are so versatile that it will not be necessary to introduce any new methods for preparing aide hydes and ketones in this chapter A few examples will illustrate this point... 

Deep fluorinalion of alkanes, ethers, acid fmlides, esters, alkyl chlorides, most ketones, ketals, orthoesters, and combinations of these functional groups produces principally the perfluonnated analogues (Table 2) Chlorine substituents (or chloro groups) usually survive fluorination... 

A solution of (R)-oxynilrilase (F.C 4.1.2.10, 100 pi., 1000 unils/ml.) is dropped onto 1.5 g of Avicel cellulose (soaked in 0.02 M sodium acetate buffer. pH 4.5). 20 mL of diisopropyl ether are added, followed by 5 mmol of ketone and 200 pL of hydrocyanic acid, and the mixture is stirred (Table 3). The catalyst is filtered off. washed with diisopropyl ether, and the combined filtrates are concentrated. 

Rideout and Breslow first reported [2a] the kinetic data for the accelerating effect of water, for the Diels Alder reactions of cyclopentadiene with methyl vinyl ketone and acrylonitrile and the cycloaddition of anthracene-9-carbinol with N-ethylmaleimide, giving impetus to research in this area (Table 6.1). The reaction in water is 28 to 740 times faster than in the apolar hydrocarbon isooctane. By adding lithium chloride (salting-out agent) the reaction rate increases 2.5 times further, while the presence of guanidinium chloride decreases it. The authors suggested that this exceptional effect of water is the result of a combination of two factors the polarity of the medium and the... 

Later, in a modification to the above system, we reported the use of an indenylruthenium complex 2 as a racemization catalyst for the DKR of secondary alcohols, which does not require ketones but a weak base hke triethylamine and molecular oxygen to be achvated. The DKR with 2 in combination with immobilized Pseudomonas cepacia lipase (PCL, trade name. Lipase PS-C ) was carried out at a lower temperature (60°C) and provided good yields and high optical purities (Table 2). This paved the way for the omission of ketones as... 

By way of graphical example of the various algebraic and geometrical concepts that are introduced in this chapter, we will make use of a measurement table adapted from Walczak etal.[ ]. Table 31.2 describes 23 substituted chalcones in terms of eight chromatographic retention times. Chalcone molecules are constituted of two phenyl rings joined by a chain of three-carbon atoms which carries a double bond and a ketone function. Substitutions have been made on each of the phenyl rings at the para-positions with respect to the chain. The substituents are CFj, F, H, methyl, ethyl, i-propyl, t-butyl, methoxy, dimethylamine, phenyl and NO2. Not all combinations two-by-two of these substituents are represented in the... 

While it is beyond the scope of this chapter to cover the asymmetric hydrosilylation of ketones and imines in any detail, a number of the more catalytically active ML combinations will be mentioned here. A full review of the area has recently appeared.138 Asymmetric hydrosilylation of carbonyl groups is usually performed with rhodium or titanium catalysts bearing chelating N- or P-based ligands. Representative results for some of the most active Rh/L combinations (Scheme 32) for addition of Si H to acetophenone are given in Table 11. 

Various combinations of tricoordinate heavy ketones have been synthesized as stable compounds by taking advantage of extremely bulky aryl substituents.52 54,161 167 Table 3 shows their selected structural parameters and spectroscopic properties. 

Amino ketones and their hydrochloride salts can be effectively hydrogenated with chiral rhodium catalysts (Table 33.5). The rhodium precatalysts, when combined with chiral phosphorus ligands such as BPPFOH 4 [20b], hydroxyproline derivatives ligands [20-24], Cy,Cy-oxo-ProNOP 15, Cp,Cp-oxoProNOP 16, and... 

Methylenesulphones are more acidic than the simple esters, ketones and cyano compounds and are more reactive with haloalkanes [e.g. 48-57] to yield precursors for the synthesis of aldehydes [53], ketones [53], esters [54] and 1,4-diketones [55] (Scheme 6.4). The early extractive alkylation methods have been superseded by solidtliquid phase-transfer catalytic methods [e.g. 58] and, combined with microwave irradiation, the reaction times are reduced dramatically [59]. The reactions appear to be somewhat sensitive to steric hindrance, as the methylenesulphones tend to be unreactive towards secondary haloalkanes and it has been reported that iodomethylsulphones cannot be dialkylated [49], although mono- and di-chloromethylsulphones are alkylated with no difficulty [48, 60] and methylenesulphones react with dihaloalkanes to yield cycloalkyl sulphones (Table 6.5 and 6.6). When the ratio of dihaloalkane to methylene sulphone is greater than 0.5 1, open chain systems are produced [48, 49]. Vinyl sulphones are obtained from the base-catalysed elimination of the halogen acid from the products of the alkylation of halomethylenesulphones [48]. 

Carbon dioxide is a symmetrical, linear triatomic molecule (0 = C=0) with a zero dipole moment. The carbon-to-hydrogen bond distances are about 1.16A, which is about 0.06A shorter than typical carbonyl double bonds. This shorter bond length was interpreted by Pauling to indicate that greater resonance stabilization occurs with CO2 than with aldehydes, ketones, or amides. When combined with water, carbonic acid (H2CO3) forms, and depending on the pH of the solution, carbonic acid loses one or two protons to form bicarbonate and carbonate, respectively. The various thermodynamic parameters of these reactions are shown in Table I. 

Numerous experimental combinations of process conditions (SS or US), hydrogenation gas (H2 or D2), and solvent (H2O or D2O) have been explored. A summary of combinations we have chosen for study is presented in Table 2. In this table it is seen that the experiments are labeled B1-B7 for 3B20L and P1-P6 for 14PD30L. The second column lists the experimental conditions, whereas the third column lists the initial system concentration based on 100 mM of substrate and the amount of catalyst used. The penultimate column lists the final (extent of reaction > 95%) selectivity to ketone (2-butanone or 3-pentanone) and the final column lists the pseudo-first order substrate loss rate coefficient. The dataset contained in Table 2 enables numerous conclusions to be made regarding the reaction systems. The differences in initial concentrations (e.g., 67 versus 100 M/g-cat.) arise from the chosen convenience of having similar activities and therefore comparable reaction times. 

A synthetic study has revealed that the combination of anhydrous hydrogen chloride and zinc(II) chloride in the presence of a nucleophile, e.g. benzenethiol, promotes the ring cleavage of cyclobutanones such as bicyclo[3.2.0]heptan-6-one (28) to provide / -sulfanyl ketones such as 3-phenylsulfanylcycloheptanone (27).63 Alternatively, iodotrimethylsilane in the presence of either mercury/water or zinc(II) iodide also converts cyclobutanones to /i-iodo ketones 29.64 The synthetic applications of these transformations are summarized in Table 5. 

Such correlation equations have been derived for many classes of compounds (Table 7.3). These examples illustrate that very good relationships are found when only members of a specific compound class are included in the LFER. One can also reasonably combine compound classes into a single LFER if only compounds that exhibit similar intermolecular interaction characteristics are used (e.g., alkyl and chlorobenzenes aliphatic ethers and ketones polychlorinated biphenyls and polychlorinated dibenzodioxins). 

Table 1.4. lists the combinations of catalytic chromium compounds and oxidants (used in excess) employed in the oxidation of alcohols to aldehydes and ketones. 

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