Acid chloride ketones from

Carboxylic acids, a-bromination of 55, 31 CARBOXYLIC ACID CHLORIDES, ketones from, 55, 122 CARBYLAMINE REACTION, 55, 96 Ceric ammonium nitrate [Ammonium hexa mtrocerate(IV)[, 55, 43 Chlorine, 55, 33, 35, 63 CHROMIUM TRIOXIDE-PYRIDINE COMPLEX, preparation in situ, 55, 84 Cinnamomtnle, a-phenyl- [2-Propeneni-tnle 2,3-diphenyl-], 55, 92 Copper(l) iodide, 55, 105, 123, 124 Copper thiophenoxide [Benzenethiol, copper(I) salt], 55, 123 CYCLIZATION, free radical, 55, 57 CYCLOBUTADIENE, 55, 43 Cyclobutadieneiron tricarbonyl [Iron, tn-carbonyl(r)4-l,3-cyclo-butadiene)-], 55,43... 

Carbon monoxide, 57, 11 Carbonyl compounds, 56, 36 Carboxylic acids, a-bromination of, 55, 31 CARBOXYLIC ACID CHLORIDES, ketones from, 55, 122 CARBYLAMINE REACTION, 55, 96 Carcinogens, list of. 56, 128 58, 168 Carveol, 56, 106 Carveol acetate, 56, 106 Catechols, 58, 125... 

The at complex from DIB AH and butyllithium is a selective reducing agent.16 It is used tor the 1,2-reduction of acyclic and cyclic enones. Esters and lactones are reduced at room temperature to alcohols, and at -78 C to alcohols and aldehydes. Acid chlorides are rapidly reduced with excess reagent at -78 C to alcohols, but a mixture of alcohols, aldehydes, and acid chlorides results from use of an equimolar amount of reagent at -78 C. Acid anhydrides are reduced at -78 C to alcohols and carboxylic acids. Carboxylic acids and both primary and secondary amides are inert at room temperature, whereas tertiary amides (as in the present case) are reduced between 0 C and room temperature to aldehydes. The at complex rapidly reduces primary alkyl, benzylic, and allylic bromides, while tertiary alkyl and aryl halides are inert. Epoxides are reduced exclusively to the more highly substituted alcohols. Disulfides lead to thiols, but both sulfoxides and sulfones are inert. Moreover, this at complex from DIBAH and butyllithium is able to reduce ketones selectively in the presence of esters. 

Intramolecular Friedel-Crafts cyclisation of the acid 1 to the 4-position takes place perfectly normally to give the tricyclic ketone. Under almost identical conditions (AlCl3/nitrobenzene/0°C), the acid chloride derived from 2 cyclised smoothly to give a 50% yield of a tricyclic ketone. This however, was shown to be 3, and not the expected product. 

A list of ketones which have been prepared by the Friedel-Crafts stannic chloride method may be found in Table VI. Yields marked by an asterisk were obtained from acid chlorides prepared by the phosphorus pentachloride procedure all others were obtained from acid chlorides prepared from thionyl chloride. 

A stereospecific synthesis of (S)-(—)-cathinone that utilizes the Friedel-Crafts reaction has been described (3/7). Reaction of the acid chloride obtained from /V-(methoxycarbonyl)-L-alanine (10) in benzene by A1C13 catalysis provided the N-protected a-amino ketone 11 with retention of chiralty 11 was deprotected by hydrolysis with potassium hydroxide. A more recently published method (408)... 

Variants of the ethyl ketone function of methadone, an aspect already broached with mention of dextromoramide, include ester, sulphone, and secondary alcohol functions in addition to (-amides. The ethyl ester analog 14a obtained by treating the acid chloride derived from methadone cyanide with ethanol is markedly inferior in potency to methadone, while the sulfone 14b (obtained by aminoalkylation of benzhydryl ethyl sulfone) is equipotent... 

The oxime 7, prepared from salicyl aldehyde, is converted with iV-chlorosuccinimide into the hydrox-amic acid chloride 8. From this, the nitrile oxide is obtained with KHCO3, which reacts regioselec-tively with styrene to give the 3,5-diaryl-4,5-dihydroisoxazole 9. Catalytic hydrogenation leads to the y -hydroxy ketone 10, which on acid-catalysed cyclodehydration gives the flavanone 11. 

Reduction of aldehydes and ketones allylic alcohols from a, 3-unsaturated aldehydes and ketones alcohols from carboxylic acid chlorides amines from aliphatic azides.21 ... 

Acetic acid formaldehyde-hydrogen chloride Ketones from prim, amines... 

Peroxyacetic acid hydrogen chloride Ketones from ethylene derivatives... 

Silicon tetrachloride stannic chloride Ketones from carboxylic acids... 

The most general methods for the syntheses of 1,2-difunctional molecules are based on the oxidation of carbon-carbon multiple bonds (p. 117) and the opening of oxiranes by hetero atoms (p. 123fl.). There exist, however, also a few useful reactions in which an a - and a d -synthon or two r -synthons are combined. The classical polar reaction is the addition of cyanide anion to carbonyl groups, which leads to a-hydroxynitriles (cyanohydrins). It is used, for example, in Strecker s synthesis of amino acids and in the homologization of monosaccharides. The ff-hydroxy group of a nitrile can be easily substituted by various nucleophiles, the nitrile can be solvolyzed or reduced. Therefore a large variety of terminal difunctional molecules with one additional carbon atom can be made. Equally versatile are a-methylsulfinyl ketones (H.G. Hauthal, 1971 T. Durst, 1979 O. DeLucchi, 1991), which are available from acid chlorides or esters and the dimsyl anion. Carbanions of these compounds can also be used for the synthesis of 1,4-dicarbonyl compounds (p. 65f.). 

The acylpalladium complex formed from acyl halides undergoes intramolecular alkene insertion. 2,5-Hexadienoyl chloride (894) is converted into phenol in its attempted Rosenmund reduction[759]. The reaction is explained by the oxidative addition, intramolecular alkene insertion to generate 895, and / -elimination. Chloroformate will be a useful compound for the preparation of a, /3-unsaturated esters if its oxidative addition and alkene insertion are possible. An intramolecular version is known, namely homoallylic chloroformates are converted into a-methylene-7-butyrolactones in moderate yields[760]. As another example, the homoallylic chloroformamide 896 is converted into the q-methylene- -butyrolactams 897 and 898[761]. An intermolecular version of alkene insertion into acyl chlorides is known only with bridgehead acid chlorides. Adamantanecarbonyl chloride (899) reacts with acrylonitrile to give the unsaturated ketone 900[762],... 

Sulfur tetrafluoride [7783-60-0] SF, replaces halogen in haloalkanes, haloalkenes, and aryl chlorides, but is only effective (even at elevated temperatures) in the presence of a Lewis acid catalyst. The reagent is most often used in the replacement of carbonyl oxygen with fluorine (15,16). Aldehydes and ketones react readily, particularly if no alpha-hydrogen atoms are present (eg, benzal fluoride [455-31-2] from benzaldehyde), but acids, esters, acid chlorides, and anhydrides are very sluggish. However, these reactions can be catalyzed by Lewis acids (HP, BF, etc). 

Vinyllithium [917-57-7] can be formed direcdy from vinyl chloride by means of a lithium [7439-93-2] dispersion containing 2 wt % sodium [7440-23-5] at 0—10°C. This compound is a reactive intermediate for the formation of vinyl alcohols from aldehydes, vinyl ketones from organic acids, vinyl sulfides from disulfides, and monosubstituted alkenes from organic halides. It can also be converted to vinylcopper [37616-22-1] or divinylcopper lithium [22903-99-7], which can then be used to introduce a vinyl group stereoselectively into a variety of a, P-unsaturated systems (26), or simply add a vinyl group to other a, P-unsaturated compounds to give y, 5-unsaturated compounds. Vinyllithium reagents can also be converted to secondary alcohols with trialkylb o r ane s. 

Ghlorohydrination with Nonaqueous Hypochlorous Acid. Because the presence of chloride ions has been shown to promote the formation of the dichloro by-product, it is desirable to perform the chlorohydrination in the absence of chloride ion. For this reason, methods have been reported to produce hypochlorous acid solutions free of chloride ions. A patented method (48) involves the extraction of hypochlorous acid with solvents such as methyl ethyl ketone [78-93-3J, acetonitrile, and ethyl acetate [141-78-6J. In one example hypochlorous acid was extracted from an aqueous brine with methyl ethyl ketone in a 98.9% yield based on the chlorine used. However, when propylene reacted with a 1 Af solution of hypochlorous acid in either methyl ethyl ketone or ethyl acetate, chlorohydrin yields of only 60—70% were obtained (10). 

The first /3 -lactam was produced by addition of a ketene to an imine and there are now many examples of this type of approach. The ketenes are most frequently generated in situ from acid chlorides by dehydrohalogenation, but have also been produced from diazo ketones, by heating of alkoxyacetylenes and in the case of certain cyanoketenes by thermolysis of the cyclic precursors (162) and (163). 

Tetrahydroharman, m.p. 179-80°, has been prepared by a number of workers by a modification of this reaction, viz., by the interaction of tryptamine (3-)5-aminoethylindole) with acetaldehyde or paraldehyde and Hahn et al. have obtained a series of derivatives of tetrahydronorharman by the use of other aldehydes and a-ketonic acids under biological conditions of pH and temperature, while Asahina and Osada, by the action of aromatic acid chlorides on the same amine, have prepared a series of amides from which the corresponding substituted dihydronorharmans have been made by effecting ring closure with phosphorus pentoxide in xylene solution. 

AkoJwIs may be obtained from aldehydes, ketones, esters, acid chlorides, and anhydrides,... 

The acylation of enamines derived from cyclic ketones, which can lead to the acyl ketone or ring expansion (692-694), was studied by NMR and mass spectroscopic analysis of the products (695,696). In a comparative study of the rates of diphenylketene addition to olefins, a pronounced activation was observed in enamines (697). Enamine N- and C-acylation products were obtained from reactions of Schiff s bases (698), vinylogous urethanes (699), cyanamides (699), amides (670,700), and 2-benzylidene-3-methylbenzothiazoline (672) with acid chlorides, anhydrides, and dithio-esters (699). 

Besides acetophenone, this reaction was also applied to p-chloro- andp-methoxyacetophenone, and even to an aliphatic ketone, acetone (although the yield was stated to be only half as large as that obtained from mesityl oxide, i.e., less than 30%, Dorofeenko and co-workers reported a 45% yield of 2,4,6-trimethylpyrylium perchlorate from acetone, acetic anhydride, and perchloric acid), and is the standard method for preparing pyrylium salts with identical substituents in positions 2 and 4. The acylating agent may be an anhydride in the presence of anhydrous or hydrated ferric chloride, or of boron fluoride, or the acid chloride with ferric chloride.Schneider and co-workers ... 

Syntheses of ketones of heterocyclic series from acid chlorides andorganometal-lic compounds 99T4177. 

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