Ethyl acetate halogenation

It is also possible to start from chloroacetaldehyde derivatives such as 1,2-dihalogeno ethyl acetate yields can reach 90% (356). These compounds can be easily obtained by addition of halogen to the double bond of vinylacetate at 0 to 10°C. 

As with Soxhlet, the preferred extraction solvent is methanol, which has been used for the extraction of alkylphenols, halogenated NPs and NPEO [13,14,36], and AEOs [37]. Other solvents that have been used are ethyl acetate for alkylphenols and short-chain NPEO [10],... 

The high reactivity of TFAT limits the number of solvents that can be used for its reactions. We have found that TFAT is unreactive towards saturated hydocarbons, benzene, and common halogenated solvents. It reacts only very slowly with nitromethane, but reacts relatively rapidly with ether, tetrahydrofuran, ethyl acetate, and acetonitrile. 

Adams platinum oxide catalyst is readily prepared from chloroplatinio acid or from ammonium chloroplatinate, and is employed for catalytio hydrogenation at pressures of one atmosphere to several atmospheres and from room temperature to about 90°. Reduction is usually carried out with rectified spirit or absolute alcohol as solvents. In some cases (e.g., the reduction of benzene, toluene, xylene, mesitylene, cymene and diphenyl ), the addition to the absolute alcohol solution of 2-5 per cent, of the volume of rectified spirit which has been saturated with hydrogen chloride increases the effectiveness of the catalyst under these conditions chlorobenzene, bromobenzene, o-, m- and p-bromotoluenes, p-dichloro- and p-dibromo-benzene are reduced completely but the halogens are simultaneously eliminated. Other solvents which are occasionally employed include glacial acetic acid, ethyl acetate, ethyl acetate with 17 per cent, acetic acid or 8 per cent, of alcohol. In the actual hydrogenation the platinum oxide Pt02,H20 is first reduced to an active form of finely-divided platinum, which is the real catalyst allowance must be made for the consumption of hydrogen in the process. 

Chloropyrido[l,2-a]pyrimidin-4-ones 399 (R = Me, Cl R1 = 6-Me X = Cl) were prepared in excellent yields when 3-unsubstituted derivatives reacted with phosphorus pentachloride in phosphoryl chloride at 105-110°C for 1.5 hours (85JHC481). Other 3-bromo- and 3-chloro-2-(chloromethyl)-4//-pyrido[l,2-a]pyrimidin-4-ones were also prepared from 3-unsaturated derivatives with halogenation agents (e.g., with N-chlorosuccinimide (NCS) in a mixture of carbon tetrachloride and ethyl acetate) (83EUP81945). 

Photo-oxidation of citronellol in polystyrene beads [120]. A sample of 3.0 g of polystyrene beads (commercial, cross-polymerized with 1% of divinylbenzene) was treated with a solution of 2 mg of tetraphenylporphyrin and 780 mg (5 mmol) of citronellol in 20 mL of ethyl acetate in a petri-dish (30 cm diameter). After 2h in a ventilated hood, the solvent has evaporated and the petri-dish was covered with a glass plate and irradiated for 5 h with a 150 W halogen lamp. The solid support was then washed with 3 x 20 mL of ethanol, the combined ethanol fractions were rota-evaporated and 900 mg of the hydroperoxide mixture (96%) was isolated as a slightly yellow oil. The hydroperoxides were quantitatively reduced to the corresponding allylic alcohols by treatment with sodium sulfite. One of these products is used in the industrial synthesis of rose oxide. 

Recrystallization of 6-nitroBIPS and its simple (methoxy, lower alkyl, halogen) substituted derivatives is often best carried out from pure ethyl acetate (i.e., free of ethanol and acetic acid) with use of decolorizing charcoal. Most dyes have a large temperature coefficient of solubility and crystallize beautifully. 

Ozonolysis of the monobromide 8 in ethyl acetate occurred also preferably at the non-halogenated double bond to form the ozonide 9(5) ... 

A variety of methods are available for the halogenadon of aldehydes and ketones, and rely on the ease of enolization of such compounds. Copper(ID chloride or bromit in ethyl acetate at reflux have been shown to be effecdve reagents and rely on the promotion of enolization by the copper ion prior to the transfer of halogen. Since these conditions tend to favor the thermodynamic enol, unsymmetrical ketones preferentially halogenate at the more highly substituted a-carbon atom. Similar selectivity is observed with NBS. 0.11... 

Tin(ll) chloride is an effective reducing agent under acidic conditions. " This inexpensive reagent selectively reduces aromatic nitro compounds in nonacidic and nonaqueous media." Nearly quantitative yields of arylamines are obtained using tin(II) chloride dihydrate in alcohol or ethyl acetate (equation 19). Under these conditions other reducible or acid sensitive groups such as aldehyde, ketone, ester, cyano, halogen and benzyl ethers are not affected. 

The halogen derivatives of ethyl acetate are compounds which have been known for some time and are used nowadays for organic syntheses both in the laboratory and in industry. They have a powerful action on the eyes and were used as war gases in the war of 1914-18. 

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