4-Ethyl-propiophenone

Propiophenone. Propiophenone [93-55-0] (ethyl phenyl ketone) is a colorless Hquid with a flowery odor. It can be prepared by the Friedel-Crafts reaction of benzene and propionyl chloride in the presence of aluminum chloride (346), or by the catalytic reaction of benzoic acid and propionic acid in the presence of water (347). Propiophenone is commercially available (348), and is sold in Japan at 2700 Y/kg (349). It is used in the production of ephedrine, as a fragrance enhancer, and as a polymerization sensitizer. 

Phenyl-2-butanol has a methyl group, an ethyl group, and a phenyl group (—Cgl ) attached to the alcohol carbon atom. Thus, the possibilities arc addition of ethylmagnesium bromide to acetophenone, addition of methylmagnesium bromide to propiophenone, and addition of phenylmagnesimn bromide to 2-butanone. 

Proline, hydroxy Lf L Ff Propionamide, N-ethyl Lf Propiophenone, 2-4-dimethyl Lf Propiophenone, para-ethyl Lf ... 

Alkylation of the hydantoin (89-2) from benzaldehyde with ethyl iodide takes place at the imide nitrogen to afford ethitoin (89-3) [93]. In much the same vein, treatment of the hydantoin (89-5) from propiophenone with methyl iodide (89-5) in the presence of a base affords mephenytoin (89-6) [94]. Replacement of the quite acidic imide proton by an aUcyl group is not required for activity the well-known anticonvulsant phenytoin (89-8) consists of simply the hydantoin obtained from benzophenone (89-7) [95] this is often formulated as its sodium salt. 

S-methyIbutyraldehyde, 3-methylbutanal (c) a-chlorovaleraldehyde, 2-chloropentanal (d) methyl isopropyl ketone, 3-methyl-2-butanone (e) ethyl phenyl ketone, 1-phenyl-1-propanone (propiophenone) (/) methyl vinyl ketone, 3-buten-2-one. The C=0 group has numbering priority over the C=C group. 

Moreover, the formation of enoxy-silanes via silylation of ketones127 by means of N-methyl-N-TMS-acetamide (1 72) in presence of sodium trimethylsilanolate (173) was reported in 1969 and since then, the use of silylating reagents in presence of a catalyst has found wide appreciation and growing utilization as shown in recent papers128-132 (Scheme 27). Diacetyl (181) can be converted by trifluoromethylsul-fonic acid-TMS-ester (182) into 2,3-bis(trimethylsiloxy)-l, 3-butadiene (7treatment with ethyl TMS acetate (7 5)/tetrakis(n-butyl)amine fluoride l-trimethylsiloxy-2-methyl-styrene (i<56)130. Cyclohexanone reacts with the combination dimethyl-TMS-amine (18 7)/p-toluenesulfonic acid to 1-trimethylsiloxy-l-cyclohexene (iSS)131. Similarly, acetylacetone plus phenyl-triethylsilyl-sulfide (189) afford 2-triethylsiloxy-2-pentene-4-one (790)132. ... 

Reserpine is extracted from powdered tablets with water saturated with ethyl acetate, after addition of a solution of propiophenone in ethyl acetate saturated with water (as internal standard). After centrifugation, the ethyl acetate layer is analysed by HPLC on a 10 pm Lichrosorb RP-8 column using methanol/0.05M sodium phosphate monobasic mixture (1 1) as the mobile phase. The flow rate is adjusted to 2 ml/minute. Detection is carried out under UV at 25U run. (Fig. 9). 

This two-step sequence can synthesize many alkylbenzenes that are impossible to make by direct alkylation. For example, we saw earlier that n-propylbenzene cannot be made by Friedel-Crafts alkylation. Benzene reacts with n-propyl chloride and AICI3 to give isopropylbenzene, together with some diisopropylbenzene. In the acylation, however, benzene reacts with propanoyl chloride and A1C13 to give ethyl phenyl ketone (propiophenone), which is easily reduced to n-propylbenzene. 

SYNS KETONE, 4-BIPHENYL ETHYL 4-PHENYLPROPIOPHENONE PROPIOPHENONE, 4 -PHENYL-... 

SYNS PHENYL ETHYL KETONE 1-PHENYL-l-PROPANONE PROPIONYLBENZENE PROPIOPHENONE USAF EK-1235... 

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