Aceto acetate

It follows therefore that ethyl malonate can be used (just as ethyl aceto- acetate) to prepare any mono or di-substituted acetic acid the limitations are identical, namely the substituents must necessarily be alkyl groups (or aryl-alkyl groups such as CjHjCHj), and tri-substituted acetic acids cannot be prepared. Ethyl malonate undergoes no reaction equivalent to the ketonic hydrolysis of ethyl acetoacetate, and the concentration of the alkali used for the hydrolysis is therefore not important. 

Pigment YeUow 13 [5102-83-0] 21100 diarjlide coupling of tetra2oti2ed 3,3 -dichloro-ben2idine with aceto acet-2,4- dimethyl-anilide... 

Acet-. acet-, aceto-, acetic, -anhydrid, n. acetic anhydride. 

Winch, if any, of the following compounds can be prepared by an aceto-acetic ester synthesis Explain. 

The aldol reaction is a carbonyl condensation that occurs between two aldehyde or ketone molecules. Aldol reactions are reversible, leading first to a /3-hydroxy aldehyde or ketone and then to an cr,/6-unsaturated product. Mixed aldol condensations between two different aldehydes or ketones generally give a mixture of all four possible products. A mixed reaction can be successful, however, if one of the two partners is an unusually good donor (ethyl aceto-acetate, for instance) or if it can act only as an acceptor (formaldehyde and benzaldehyde, for instance). Intramolecular aldol condensations of 1,4- and 1,5-diketones are also successful and provide a good way to make five-and six-inembered rings. 

Aspirin (34) is an available protected form of (38) and aceto acetate is an activated form of ethyl acetate, instead of the more usual malonate. 

The addition of active methylene compounds (ethyl malonate, ethyl aceto-acetate, ethyl plienylacetate, nitromethane, acrylonitrile, etc.) to the ap-double bond of a conjugated unsaturated ketone, ester or nitrile in the presence of a basic cataljst (s ium ethoxide, piperidine, diethylamiue, etc.) is known as the Michael reaction or Michael addition. The reaction may be illustrated by the addition of ethyl malonate to ethyl fumarate in the presence of sodium ethoxide hydrolysis and decarboxylation of the addendum (ethyl propane-1 1 2 3-tetracarboxylate) yields tricarballylic acid ... 

The other ketone bodies are derived from acetoacetate P-hydroxybutyrate, by reduction with the involvement of NAD-dependent hydroxybutyrate dehydrogenase, and acetone, by decarboxylation of acetoacetate with the participation of aceto-acetate decarboxylase ... 

The preparation of dithianes from enamines by reaction with trimethylene dithiotosylate (propane-1,3-dithiol di-p-toluenesulfonate) has been applied with enamines derived from oholostan 3 one, aceto-acetic ester, and phenylacetone.6 7 Reactions of trimethylene dithiotosylate with hydroxymethylene derivatives of ketones also give rise to dithianes thus the hydroxymethylene derivative of cholest-4-en-3-one can be converted to 2,2-(trimethylenedithio)cholest-4-en-3-one. 1,3-Dithiolanes are obtained in a similar manner by reaction of ethylene dithiotosylate1 with the appropriately activated substrate.5,7... 

For such cases in which the two forms have been brought to light solely as a result of improved experimental methods, the term tauto-merism " has been modified to desmotropism In desmotropic substances the tautomeric relations are therefore particularly clear and well defined numerous examples have become known, which now also include aceto-acetic ester. The case of acetylacetone is quite similar, but here the formation of the enol-form is much more favoured. The liquid substance contains up to 80 per cent of enol. 

Ethyl-a-Keto-y-dimethylaminobutyrate p-Acetylphenylhydrazone. (JMC, 7, 144 (1966)). 40 g of p-aminoacetophenone in 250 ml of water and 143 ml of coned hydrochloric acid is diazotized at 0-5° with 21 g of sodium nitrite in 200 ml of water. To the resulting solution is added 60.3 g of ethyl a-(2-dimethylaminoethyl)aceto-acetate followed by 63 g of sodium acetate. Raise the pH to 6.5 and maintain with the addition of 3 N NaOH (also use the 3 N for the initial raise to 6.5). Stir, with external cooling for 2 hours, make basic, and extract with three 400 ml portions of ehloroform. Combine the extracts and dry over sodium sulphate, eoneentrate in vacuo. Crystallize the residue with a mixture of benzene-petroleum ether, after purification with charcoal, to get 65 g. Crystallize two more times to get a melting point of 84-85°. 

Acetyluracil — Ethyl 2-hydroxy-4-methyl-5-pyrimidinecarboxylate (XXXVI), which is prepared by the cyclization of the ureidomethylene derivative of aceto-acetic ester, can be caused to rearrange into 5-acetyluracil (XXXVII) in dilute alkali [304]. Compound (XXXVII) can also be prepared from diketene and ethyl carbamate, followed by treatment with ethyl orthoformate and cyclization with ammonia [305]. 

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