Ethyl 2-methylacetoacetate

A 6 M solution of methylamine in absolute ethanol containing 34 g. (1.1 moles) of amine is cooled while 100 g. (1.0 mole) of ethyl acrylate is added slowly. After standing 2 days the mixture is distilled and 

---

Nitrosohydroxylamino)-1-propanoic Acid or a-lsonitraminopropionic Acid a-[Nitroso-hydroxylamino] -propionsaure or a-Isonitra-mino-propionsaure HO.N(NO).CH(CH3 ).COOH mw 134.09, N 20.89%. It is stable only in solns. May be prepd by warming with soda the crude soln obtained by the action of nitric oxide on ethylic methylacetoacetate, until the alcohol is driven off the acid is then precipitated as the Lead Salt, PbC3H4N204, which is explosive Refs 1) Beil 4, 576 2) W. Traube, Ber 28,... 

In the electrolysis of sodium ethyl methylacetoacetate (50) in DMF one of three main products was 4-ethoxycarbonyl-3,4-dimethylcyclohex-2-enone (53)... 

Japp and Klingemann found that benzenediazonium salt 2 coupled with ethyl methylacetoacetate 1 in alkaline solution to give the phenylhydrazone of ethyl pyruvate 3 with elimination of acetic acid. However, if the ketonic ester was first hydrolyzed with alkali and then coupled, the product was monophenylhydrazone 10, with carbon dioxide being eliminated rather than acetic acid.6... 

The catalytic reaction of buta-1,3-diene with ethyl methylacetoacetate in the presence of [Pd(T)2-buta-l,3-diene) R2P(CH2)nPR2 l complexes has been investigated . The product was found to be a mixture of 1 1 adducts and the reaction to be fastest when n=2 and R = Pr in dichloromethane as the solvent. The X-ray crystal structure of a side product [ ( H n -CgHi2)Pd 2 Me2P(CH2)2PMe2 ] (42), formed by dimerisation of the butadiene ligand, has been determined. 

Earlier reported syntheses have been shown to give isoxazolin-5-ones. Other isoxazolin-3-ones have been prepared by the reaction of methylacetoacetic esters and hydroxylamine. An additional synthesis was reported by the action at 0°C of hydroxylamine on ethyl -benzoylpropionate to produce an insoluble hydroxamic acid which cyclized on acid treatment. The hydroxamic acid acetal was similarly transformed into the isoxazolin-3-one (Scheme 149) (71BSF3664, 70BSF1978). 

Hydroxy-2-methyl-4//-pyrido[l,2-n]pyrimidin-4-one was prepared in the reaction of 2-amino-3-benzyloxypyridine and ethyl acetoacetate at 60 °C, then at 100 °C for 3 h in 22% yield (96MIP1). Reaction of 2-amino-3-hydroxypyridine and ethyl 2-methylacetoacetate in a 1 2 mixture of... 

Cas/liquid reaction 5 [CL 5] Fluorination of ethyl 2-methyl-3-oxobutanoate (ethyl-2-methylacetoacetate) [16]... 

Effects of Ethyl 2-Methylacetoacetate (EMA) on the Algal Antioxidant Enzymes Activity 150... 

In our previous research, we found that the antialgal allelochemical Ethyl 2-Methylacetoacetate (EMA) caused loss of cell membrane integrity. It hinted that EMA may cause a change in the membrane. It is reported that environmental stress may increase the concentration of ROS in plant cell. The excessive ROS may cause a decrease of antioxidation enzymes activity and lipid peroxidation. The effect of EMA on the activity of SOD and POD and lipid fatty acids of Chlorella pyrenoidosa, Chlorella vulagaris and Microcystis aeruginosa were evaluated to elucidate the mode of action of EMA. 

Methyl Ethyl Ketone. 1 mole (20 g) of methylacetoacetic ester are refluxed with 250 cc of baryta water (saturated) until the oily layer disappears. Distill on a water bath to 90°. Stir violently or shake for three hours with a saturated solution of sodium bisulfate, and collect the crystals and distill with an excess of dilute sulfuric acid at 90°. The distillate is dried over calcium chloride and distilled again, retaining the fraction at 79-82°. Yield 70% theoretical (7 g). 

Similar investigations were reported by this group using /S-oxoesters as the precursors to be aminated products in the presence of CaO and 3n as amination reagent . Ethyl acetoacetate gave a-monoaminated and a-bisaminated products (Scheme 35) depending on the substrate base ratio. An A-aminated product was also obtained in the amination of ethyl a-methylacetoacetate. 

Ethyl orthoacetate, 48 Ethyl orthobenzoate, 54 Ethyl orthobromoacetate, 60 Ethyl orthodibromoacetate, 60 Ethyl orthoformate, 50 Ethyl orthothioformate, 50 Ethyl a-phenylazo-a-methylacetoacetate, 299... 

In the recent patent literature a procedure is given for coupling a diazonium salt with ethyl a-methylacetoacetate to afford an azo compound which could be used as an acetylating agent because its acetyl group was readily cleaved under mild conditions [26], In the coupling reaction, relatively weak bases such as pyridine, picolines, quinoline, and collidine are said to be effective. The example is given here for illustration only. It is to be noted that this is a composition of matter patent. 

Although other condensation reactions with 4-aminopyridine are reported to fail, they have in most cases succeeded with 4-aminoquinoline.59 Dey and Joullie87 have prepared a series of trifluoro-methylbenzo[A]-l,6-naphthyridines by condensing ethyl trifluoro-methylacetoacetate with 4-aminoquinaldine. 

The dicationic species have also been obtained from /3-ketoacids, fi-ketoesters, and /-i-ketoamides in superacid solutions (Table 1, entries 2-4). Diprotonated acetoacetic acid (75) can be observed by low-temperature NMR under stable ion conditions.34 Likewise, diprotonated methylacetoacetate (77) can be observed by NMR at temperatures lower than — 80°C in FS03H-SbF5-SC>2 solution.35 With ethyl acetoac-etate in HF-SbFs, the equilibrium constant for the dication-monocation equilibrium has been estimated to be at least 107, indicating virtually complete conversion to the superelectrophile.35 The /3-ketoamide (78) is found to give the condensation products 95 in good yield from CF3SO3H and the superelectrophile 79 is proposed as the key intermediate in the condensation reaction (eq 25 ).27... 

Dicarbonyl compounds such as ethyl a-methylacetoacetate (54) can be efficiently alkylated in good yields with vinyl ethers in the presence of Cu2+ and Mn3+ as shown in... 

---