2-Acetyl cyclohexanone, acidity

Apart from the reaction of cyclohexanecarboxylic acid with methyllithium, cyclohexyl methyl ketone has been prepared by the reaction of cyclohexylmagnesium halides with acetyl chloride or acetic anhydride and by the reaction of methylmagnesium iodide with cyclohexanecarboxylic acid chloride. Other preparative methods include the aluminum chloride-catalyzed acetylation of cyclohexene in the presence of cyclohexane, the oxidation of cyclohexylmethylcarbinol, " the decarboxylation and rearrangement of the glycidic ester derived from cyclohexanone and M)utyl a-chloroj)ropionate, and the catalytic hydrogenation of 1-acetylcycIohexene. "... 

Biological. Microbial degradation products reported include cyclohexanol (Dugan, 1972 Verschueren, 1983), l-oxa-2-oxocycloheptane, 6-hydroxyheptanoate, 6-oxohexanoate, adipic acid, acetyl-CoA, succinyl-CoA (quoted, Verschueren, 1983), and cyclohexanone (Dugan, 1972 Keck et al 1989). 

A similar acetylation procedure (without p-toluenesulfonic acid) has been employed to prepare other /3-diketones.5 As examples, cyclohexanone was converted to 2-acetylcyclohex-anone (73%) cyclopentanone yielded 2-acetylcyclopentanone (80%) 3-pentanone yielded 3-methyl-2,4-hexanedione (81%) dibenzyl ketone yielded l,3-diphenyl-2,4-pentanedione (72%), and acetophenone gave benzoylacetone (70%). 

Treatment of acetone with uranium(VI) fluoride in the vapor phase at room temperature gives13 some acetyl fluoride, along with much polymeric material. Under the same conditions, cyclohexanone also produces an unidentified acid fluoride initially, but this is then consumed to give polymeric material. 

Walther et al. improved the Na0Ph/C02 system by tuning the role of the solvent, such that the carboxylation of acetone was carried out selectively by sodium phenoxide with N-methyl-caprolactam under 0.1 MPa C02 to afford 3-ketoglutaric acid in 65% yield [34]. The same authors reported the conversion of acetyl-naphthalene (acetonaphthone) to acetyl-naphthalene carboxylic acid with 84% yield, and of cyclohexanone to cyclohexane-2,6-dicarboxylic acid in 56% yield. 

On successive treatment with trimethyloxonium tetrafluoroborate, triethylamine and aqueous acid, oxime acetate 83 prepared from cyclohexanone oxime and Ac20 yields a-acetoxy ketone 87 (Scheme 7). A similar result is obtained with other symmetric ketones including 4-heptanone, deoxybenzoin and dibenzyl ketone. 87 can also be formed by the reaction of cyclohexanone and O-acetyl-Af-methylhydroxylamine hydrochloride upon hydrolysis. If the reaction time is prolonged prior to hydrolysis, ketoamide 89 is isolated as the main product. The key step of the reaction is the [l,3]-acetoxy shift of 7V-acetoxyenamine 85 to the a-acetoxyimine 86. The formation of 89 provides support for the intermediacy of acetoxyimine 86 in the reaction sequence. The evidence available suggests that the [l,3]-acetoxy migration proceeds via a Claisen-type rearrangement (Scheme 7)78. 

Moreover, it has been shown102 that under conditions of electrophilic catalysis by acetyl cations the addition of ketones to nitriles proceeds more rapidly than the self-condensation of ketones shown in equations 34-36. Thus, cyclohexanone reacts with both benzonitrile and acetonitrile in the presence of perchloric acid/acetic anhydride mixture to form Af-acyliminium salts 186 which are then converted to the Af-acylimines 187. The /Lacylaminoketones 9773 did not form the salts 186 in a control experiment... 

Lead tetraacetate oxidizes oximes to various products. For exanqrle, the oxime of cyclohexanone gives a-acetoxynitrosocyclohexane in 35% yield.Aldoximes react with lead tetraacetate to give nitrile oxides which then yield acetyl hydroxamates 1 reaction with acetic acid. ... 

The solid monoacelie acid complex (hygroscopic) can be made by saturating an ethylene chloride solution of acetic acid with boron trifluoride, Altering, and washing the precipitate with more solvent the liquid diacetic acid complex remains in solution. The solid complex is recommended for the acetylation of a ketone, such as cyclohexanone. Thus acetic acid is stirred in an ice bath and boron trifluoride... 

In the simplest form of the Abramov reaction, the phosphorus-containing reactant is hypophosphorous acid (phosphinic acid) or an ester thereof, and in the reactions between the acid and formaldehyde or benzaldehyde the initial product is the phosphinic acid 144 (R = H or Ph.). However, the reaction can proceed further to give the bis(l-hydroxyalkyl)phosphinic acid (145 R = H or Ph) the latter (R = Ph) reacts readily with yet more benzaldehyde to give its benzylidene derivative, 5-hydroxy-2,4,6-triphenyl-1,3,5-dioxaphosphorinane 5-oxide (146 R = Ph). When acted on by a second mole of cyclohexanone in the presence of acetyl chloride, (l-hydroxycyclohexyl)phosphinic acid (147) gives the novel phosphinic chloride 148, characterized as the free acid 149 following ready hydrolysis A reaction between a phosphinic acid (150) and a second (non-identical) carbonyl compound leads to an unsymmetrical phosphinic acid (151). Esters of symmetrical 1, r-dihydroxy-substituted phosphinic acids are preparable from hypophosphite esters, H2P(0)0R ". ... 

Reference has also already been made (Chapter 2, Section A.7) to the reaction which takes place between cyclohexanone and PhPCl2, and through which (1-chlorocyclo-hexyl)phenylphosphinic acid was obtained as an illustration of this synthetic route to a (1-chloroalkyl)phosphinic acid. Mixtures of the same reactants which also contain water or an alcohol or a mixture of cyclohexanone, acetyl chloride and phenylphosphonous acid yield the isomeric (l-hydroxycyclohexyl)phenylphosphinic chloride 230 ". The same compound was also formed when a 1 1 mixture of phenylphosphonous dichloride and phenylphosphonous acid (phenylphosphinic acid) was allowed to interact with cyclohexanone, no addition occurring between the acid and the ketone in the absence of the PhPCl2. The formation of230 was therefore depicted as the addition of the cyclohexanone... 

Reduced phenanthridines have been prepared from anilines and derivatives of cyclohexanone. In the first reported example, Borsche obtained 6,9-dimethyl-7,8,9,I0-tetrahydrophenanthridine (130a) in 15% overall yield by condensing 6-acetyl-3-methylcyclohexanone with aniline and cyclizing the resultant anil (129a) with sulfuric acid. Although the anil (129b) of 2-acetylcyclohexane-l,3-dione cyclizes in... 

Desmotropic with cyclohexanone. Its esters are obtained by prolonged boiling of cyclohexanone with the appropriate acid anhyefride. Acetyl b.p. 180 2 . 

PCL can be synthesised using two methods, namely by the condensation of 6-hydroxycaproic acid and by the ring-opening polymerisation (ROP) of the cycUc e-caprolactone. This monomer is typically produced by the Baeyer—ViUiger oxidation of cyclohexanone with acetyl hydroxyperoxide (Lecoq et al., 1988). 

All four herbicides belong to completely different chemical classes sethoxydim is a cyclohexanone, fluazif op-butyl a phenoxyphenoxy-type con und, imazaquin an imidazolinone, and chlorimuron-ett l a sulfonylurea. The mode of action of fluazifop-butyl and imazaquin is inhibition of acetyl-CoA carboxylase (ACC) (, 7 ) Obviously, this is reflected by the similarity of the response patterns. The way it corresponds is not a direct one we can say nothing ed>out fatty acid biosynthesis inhibition by looking at the response pattern. What we see is the influence on other meted>olites, which are in most cases only indirectly connected with fatty acid biosynthesis. But the patterns are strikingly similar. 

Route A involves the protection of the hydroxyl groups of ntj/o-inositol at C-1 and C-2 as the cyclohexanon ketal, and acetylation of the remaining hydroxyl groups followed by removal of the protecting group from C-1 and C-2. The resulting 3,4,5,6-tetra-O-acetyl-myo-inositol is converted to the 1,2-thionocarbonate, from which tetra-O-acetyl conduritol B is obtained by the removal of sulfur and carbon dioxide with trimethyl phosphite. Deacetylation and epoxidation with peroxy acids give the desired product. 

Resin Bound CyEIC Piscopio, at Amgen, reported a synthesis of odorless resin-bound CIC Izh based on Armstrong s CIC [108]. It can be prepared from 4-(4-hydroxyphenyl)-cyclohexanone using Merrifield as a base resin. Loading in the 0.7-0.8 mmol/g range was achieved and reactions can be monitored by on-bead Fourier transform infrared spectroscopy. Hulme and coworkers have employed the resin-bound CIC Izh in the so-called UDC (Ugi/De-Boc/Cyclization) strategy to synthesize bicyclic y-lactam 304 [109]. The U-4CR of resin-bound CIC Izi, y-keto acid lOza and amine 6zg affords resin-bound y-lactam 304. Acetyl chloride... 

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