Benzoylpropionic Acid

Hydroxyl group Adamantane-l-carboxylic acid chloride. 0-Benzoylpropionic acid. Ethyl vinyl ether. 4-Methoxy-5,6-dihydro-2H-pyrane. p-Nitrophenyl chloroformate. 

Y-Phenylbutyric acid. Prepare amalgamated zinc from 120 g. of zinc wool contained in a 1-litre rovmd-bottomed flask (Section 111,50, IS), decant the liquid as completely as possible, and add in the following order 75 ml. of water, 180 ml. of concentrated hydrochloric acid, 100 ml. of pure toluene (1) and 50 g. of p benzoylpropionic acid. Fit the flask with a reflux condenser connected to a gas absorption device (Fig. II, 8, l,c), and boil the reaction mixture vigorously for 30 hours add three or four 50 ml. portions of concentrated hydrochloric acid at approximately six hour intervals during the refluxing period in order to maintain the concentration of the acid. Allow to cool to room temperature and separate the two layers. Dilute the aqueous portion with about 200 ml. of water and extract with three 75 ml. portions of ether. Combine the toluene layer with the ether extracts, wash with water, and dry over anhydrous magnesium or calcium sulphate. Remove the solvents by distillation under diminished pressure on a water bath (compare Fig. II, 37, 1), transfer the residue to a Claisen flask, and distil imder reduced pressure (Fig. II, 19, 1). Collect the y-phenylbutyric acid at 178-181°/19 mm. this solidifies on coohng to a colourless sohd (40 g.) and melts at 47-48°. 

Friedel-Crafts Acylation. The Friedel-Crafts acylation procedure is the most important method for preparing aromatic ketones and thein derivatives. Acetyl chloride (acetic anhydride) reacts with benzene ia the presence of aluminum chloride or acid catalysts to produce acetophenone [98-86-2], CgHgO (1-phenylethanone). Benzene can also be condensed with dicarboxyHc acid anhydrides to yield benzoyl derivatives of carboxyHc acids. These benzoyl derivatives are often used for constmcting polycycHc molecules (Haworth reaction). For example, benzene reacts with succinic anhydride ia the presence of aluminum chloride to produce P-benzoylpropionic acid [2051-95-8] which is converted iato a-tetralone [529-34-0] (30). 

Perumal investigated a novel variation that involved the combination of a Vilsmeier reaction with a Paal-Knorr condensation. Reaction of 3-benzoylpropionic acid (87) under Vilsmeier conditions furnished chloroformylfuran 88 in 75% yield, while reaction of acetonylacetone (89) provided formylfuran 90 in 60% yield." ... 

ESTER, 43, 100 BenzOpyrazole, 43, 69 3-Benzoylpropionic acid, condensation with benzaldehyde to give a-benzylidene-y-phenyl-A t-bu-tenolide, 43, 3... 

Problem 16.81 Give steps for the following preparations (a) 1-phenylpropane from /3-phenylpropionic acid, (6) /3-benzoylpropionic acid from benzene and succinic acid. 

The preparation of the cyclic ketone a-tetralone possesses a number of interesting features. Succinic anhydride is condensed with pure benzene in the presence of anhydrous aluminium chloride (slightly over two equivalents see 1 above) to yield (3-benzoylpropionIc acid ... 

Beckmann rearrangement of, 729,741 p-Benzoquinone, 745 Benzoylacetone, 865 o-Benzoylbenzoic acid, 728, 739 Benzoyl chloride, 791, 792 Benzoyl glycine, 584 Benzoyl peroxide, 807 determination of, 809 Benzoyl piperidine, 489, 492 P-Benzoylpropionic acid, 728, 737 P-Benzoylpropionitrfle, 911, 912 Benzoyl-p-toluidide, 582, 583 Benzyl acetate, 780, 783 Benzylacetophenone, 726, 734 Benzyl alcohol, 706,711, 811,812,884 N-Benzylamid es 394 table of, 395 ... 

The oxidation of substituted /3-benzoylpropionic acids by PFC follows the Hammett relation with a negative reaction constant. A possible mechanism for the oxidation has been discussed.5 The oxidation of maleic, fumaric, crotonic, and cinnamic acids by PCC is of first order with respect to PCC and the acid. The oxidation rate in 19 organic solvents has been analysed by Kamlet s and Swain s multiparametric equations. A mechanism involving a three-centre transition state has been postulated.6 The relative reactivity of bishomoallylic tertiary alcohols toward PCC, to yield substituted THF products via the tethered chromate ester, is dependent only on the number of alkyl groups. This observation suggests a symmetrical transition state in this intramolecular Cr(VI)-alkene reaction.7 Mechanisms have been proposed for the oxidation of 2-nitrobenzaldehyde with PBC8 and of crotonaldehyde with tetraethylammonium chlorochromate.9... 

Isonitrosopropiophenone has been prepared from esters of a-benzoylpropionic acid by a process involving saponification, nitrosation, and decarboxylationfrom phenylmethylglyoxal by the action of hydroxylamine from propiophenone by treatment with amyl nitrite, methyl nitrite, or butyl nitrite. ... 

B-Benzoylpropionic Acid (13, 13) From phenylmagnesium bromide and succinic anhydride. Koiippa and ROERUAisr, Ann. 509, 259 (1934). 

Aryl-substituted y keto acids are readily obtained by acylation of aromatic compounds with succinic anhydride, e.g., /S-benzoylpropionic acid (85%). ... 

Several a-keto acids are easily obtained by hydrolysis of acyl cyanides. An improved procedure using cuprous cyanide in the preparation of the acyl cyanides is described. Hydrolysis of the acyl cyanides by cold concentrated hydrochloric acid is described for pyruvic acid (73%), a-ketobutyric acid, and benzoylformic acid (77%). Isovaleryl cyanide is not hydrolyzed under these conditions. Alkaline hydrolysis has been found to be more successful than acid hydrolysis in the preparation of the y-keto acid, a-phenyl-/S-benzoylpropionic acid (76%). ... 

Catalytic hydrogenation over palladium-on-charcoal with perchloric acid promoter is more satisfactory than the Clemmensen method for the reduction of a-phenyl-/3-benzoylpropionic acid to a,y-diphenylbutyric acid (83%). Several other keto acids have been successfully hydrogenated over this catalyst. ... 

Benzoylacrylic acid has been prepared by the condensation of acetophenone and chloral to l,l,l-trichloro-2-hydroxy-3-benz-oylpropane, followed by hydrolysis to the corresponding acid and dehydration by the action of iodine, potassium iodide, and sodium carbonate on 7-phenylisocrotonic acid by bromination of /3-benzoylpropionic acid and subsequent dehydrohalogena-tion 1 and by the action of phenylzinc chloride on maleic anhydride. The present method is based on the work of von Pech-mann and others. ... 

Amalgams. In effecling Clemmenscn-Marlin rcdiiclion of (l-benzoylpropionic acid to Y-phenylbutyric acid. Martin shook a mixture of 120 g, of mossy zinc, 12 g. of mercuric chloride, 20(1 ml. of WHter, and 5-6 ml. of concU. hydrochloric... 

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