Ethyl formate reaction

Ethylene carbonate, reaction with potassium thiocyanate, 42, 59 Ethylene sulfide, 42, S9 Ethyl formate, reaction with cyclo-hexylamine, 41, 14 Ethyl- -hexylamine, 43, 47 5-(2-Ethylhexyl)-l,2,3,4,5-pentachloro-cyclopentadiene, 43, 93 Ethylhydrazinium hydrogen oxalate,... 

The one-carbon fragment is ethyl formate. This reaction is important as a method of control since it occurs only on one side of the carbonyl group that is it is regioselective. The reason is that this product can itself enohse in... 

Even though form amide was synthesized as early as 1863 by W. A. Hoffmann from ethyl formate [109-94-4] and ammonia, it only became accessible on a large scale, and thus iadustrially important, after development of high pressure production technology. In the 1990s, form amide is mainly manufactured either by direct synthesis from carbon monoxide and ammonia, or more importandy ia a two-stage process by reaction of methyl formate (from carbon monoxide and methanol) with ammonia. 

Esters of high volatility, such as methyl formate, methyl acetate, and ethyl formate, have lower boiling points than those of the corresponding alcohols, and therefore can be readily removed from the reaction mixture by distillation. 

Deacylations are known. C-Acyl groups in 1,3,4-thiadiazoles are cleaved by sodium ethoxide in ethanol (68AHC(9)165). Imidazole-2-carbaldehyde behaves similarly, yielding imidazole and ethyl formate this reaction involves an ylide intermediate. 3-Acylisoxazoles (405) are attacked by nucleophiles in a reaction which involves ring opening (79AHC(25)147). 

A total of 3 g (0.13 moles) of sodium hydride is added to a solution consisting of 10 g of 17 -hydroxy-5a-androstan-3-one (36 mmoles) in 200 ml of benzene and 10 ml of ethyl formate. The reaction mixture is allowed to stand under nitrogen for 3 days followed by dropwise addition of 10 ml of methanol to decompose the excess of sodium hydride. The solution is then diluted with 300 ml water and the layers are separated. The basic aqueous solution is extracted with ether to remove neutral material. The aqueous layer is acidified with 80 ml of 3 A hydrochloric acid and the hydroxymethylene steroid is extracted with benzene and ether. The combined organic extracts are washed with water and saturated sodium chloride solution and then dried over magnesium sulfate and concentrated. The residue, a reddish-yellow oil, crystallized from 10 ml of ether to yield 9.12 g (83%) of 17 -hydroxy-2-hydroxymethylene-5a-androstan-3-one mp 162-162.5°. Recrystallization from chloroform-ether gives an analytical sample mp 165-165.5° [a]o 53° (ethanol) 2 ° 252 mjj. (g 11,500), 307 m u (e 5,800). 

In 1922 Majima and Kotake reported that 3-formylindole (209) could be obtained in yields of up to 40% by the action of a fivefold excess of ethyl formate on indole magnesium iodide in anisole at low temperatures. However, they also claimed that only traces of the aldehyde were obtained when the reaction was carried out in ether. ... 

Interposition of a methylene group between the phenyl ring and the heterocycle leads to the benzyldiami nopyrimidines, a class of compounds notable for their antibacterial activity. Condensation of hydrocinnamate 54 with ethyl formate leads to the hydroxymethylene derivative 55. In this case, too, the heterocyclic ring is formed by reaction with guanidine. This sequence probably involves initial addition-elimination to the forniyl carbon to form 56 cyclization in this case involves simple amide formation. Tautomerization then affords the hydroxy derivative 57. This is converted to tetroxoprim (58) by first... 

Reaction of ethyl formate with perhydroisoquinolone 54, in the presence of strong base leads to the (5-foimylketone 55 condensation of that product with hydrazine leads to the formation of a new pyrazole ring. This product, quinpirole (56), is an antihypertensive agent [11]. 

J mol ). This is additional evidence in favor of rate limitation by inner diffusion. However, the same reaction in the presence of Dowex-50, which has a more open three-dimensional network, gave an activation energy of 44800 J mol , and closely similar values were obtained for the hydrolysis of ethyl acetate [29] and dimethyl seb-acate [30]. The activation energy for the hydrolysis of ethyl acetate on a macroreticular sulphonated cationic exchanger [93] is 3566 J mol . For the hydrolysis of ethyl formate in a binary system, the isocomposition activation energy (Ec) [28,92] tends to decrease as the solvent content increases, while for solutions of the same dielectric constant, the iso-dielectric activation energy (Ed) increases as the dielectric constant of the solvent increases (Table 6). 

The mixed Claisen condensation of two different esters is similar to the mixed aldol condensation of two different aldehydes or ketones (Section 23.5). Mixed Claisen reactions are successful only when one of the two ester components has no a hydrogens and thus can t form an enolate ion. For example, ethyl benzoate and ethyl formate can t form enolate ions and thus can t serve as donors. They can, however, act as the electrophilic acceptor components in reactions with other ester anions to give mixed /3-keto ester products. 

Mixed Claisen-like reactions can also be carried out between an ester and a ketone, resulting in the synthesis of a jS-diketone. The reaction works best when the ester component has no a hydrogens and thus can t act as the nucleophilic donor. For example, ethyl formate gives high yields in mixed Claisen condensations with ketones. 

In the mixed Claisen reaction of cyclopentanone with ethyl formate, a much higher yield of the desired product is obtained by first mixing the two carbonyl components and then adding base, rather than by first mixing base with cyclopentanone and then adding ethyl formate. Explain. 

Ethyl formate, mixed Claisen condensation reaction of,... 

Grignard reaction, (Continual) with ethyl formate, 16, I r with ethyl orthoformate, 16, 41 with water, 11, 84... 

Cyclohexene, purification of, 41, 74 reaction with zinc-copper couple and methylene iodide, 41, 73 2-CyclohEXENONE, 40,14 Cydohexylamine, reaction with ethyl formate, 41, 14... 

Block one side of the ketone by introducing a removable group. Alkylation takes place on the other side the blocking group is then removed. A common reaction for this purpose is formylation with ethyl formate (10-119) this generally blocks the less hindered side. The formyl group is easily removed by alkaline hydrolysis (12-41). 

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