Propiophenone, /3-dimethylamino

Benzoylpropionitrile. To a mixture of 21 4 g. of p dimethylamino propiophenone hydrochloride, 13 0 g. of potassium cyanide in a 500 ml. flask, add 260 ml. of boiling water heat the heterogeneous mixture under reflux for 30 minutes. Part of the dimethylamine, which is eliminated in the reaction, distils collect this in dilute hydrochloric acid. Cool the reaction mixture in ice the oil sohdifies and crystals form from the aqueous layer. Collect the solid (crude p benzoylpropiouitrile, 10-5 g.) by suction filtration and recrystallise it from benzene - light petroleum (b.p. 40-60°) it separates as almost colourless blades, m.p. 76°. 

Insuasty, B. Abonia, R. Quiroga, J. Salcedo, A. Kolshorn, H. Meier, H. 1-Alkyl and azeto[l,2-a][l,5]benzodiazepine derivatives in the reaction of o-phenylenediamine with 3-(dimethylamino)propiophenones. Ear. J. 

Yamase, 1 Kuroki. N., and Konishi, K Reactive dyes. XIX. Reactive dyes containing io-(dimethylamino)propiophenone groups, Kogyo Kagaku Za.s.shi. 98,1713,1965 Client. Ahstr, 64, 11350, 1966. 

SYNS 4 -(DIMETHYLAMINO)-3-(4-PHENYL-l,2,5,6-TETRAHYDRO-l-PYRIDYL)PROPIOPHENONE PROPIOPHENONE,4 -piMETHYLAMINO)-3-(4-PHEN YL-l,2,3,6-TETRAHYDRO-l-PYRIDYL)-... 

The literature of this reaction to 1942 has been reviewed. Later observations have been made. The synthesis of /3-dimethylamino-propiophenone (72%) exhibits a typical procedure. ... 

Dimethylamino)propiophenone hydrochloride 715 Acetophenone (60 g, 58.5 ml, 0.5mole), dimethylammonium chloride (52.7 g, 0.65 mole), and paraformaldehyde (19.8 g, 0.66 mole) are placed in a round-bottomed flask (capacity 500 ml). A mixture of concentrated hydrochloric acid (d 1.19 1 ml) and 95% ethanol (80 ml) is added and the whole is boiled under reflux for 2 h. If the yellowish solution produced is turbid it is filtered through a heated filter and, whilst still hot, diluted with acetone (400 ml). The solution is allowed to cool slowly to room temperature and placed in a refrigerator overnight. The crystals formed are filtered off, washed with acetone (25 ml), and dried for 2.5 h at 40-50° this crude product is obtained in 68-72% yield (72-77 g) and melts at 138-141°. It is somewhat hygroscopic and if dried for a further 4 h melts at 152-153°. It can be recrystallized by dissolution in 95% ethanol (85-90 ml) and slow addition of acetone (450 ml) recovery is then about 90%, the m.p. being 155-156°. 

When 3-(dimethylamino)propiophenone hydrochloride is boiled for 0.5 hour with aqueous potassium cyanide solution, 4-oxo-4-phenylbutyronitrile is formed in 67% yield, dimethylamine being split off 806... 

Heating 3-(dimethylamino)propiophenone with a ketone at 160° for 20 minutes affords a 1,5-diketone, as in the following example (95% yield) 810... 

The Mannich reaction consists in the condensation of formaldehyde with ammonia or a primary or a secondary amine and a compound containing at least one hydrogen atom of pronounced reactivity the active hydrogen atom may be derived from a methylene group activated by a neighbouring keto group, or from a nitroparaffin, or it may be the o- or p-hydrogen atoms in phenols. Thus when acetophenone is boiled in alcoholic solution with formaldehyde and dimethylamine hydrochloride, the Mannich base 3-dimethylamino-propiophenone hydrochloride (I) is readily formed ... 

Synonyms. 2-(Dimethylamino) propiophenone 2-(Dimethylamino)-l-phenyl-propanone N-Methylephedrone Dimepropion a-(Dimethylamino) propiophenone Benzoyl-a-dimethyl-amino ethane. 

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