4- Bromopropiophenone

Bromopropiophenone from aluminum chloride catalyzed bromination of propiophenone, 40, 9 3-Bromo-4-tolualdehyde from aluminum chloride catalyzed bromination of J>-tolualdehyde, 40, 9 sec-Butyl acrylate, 41, 62 sec-Butyl alcohol, esterification of cro-tonic add with, 41, 60 esters with a,/3-unsaturated adds, 41, 62... 

Bromopropiophenone from aluminum chloride catalyzed bromination of propiophenone, 9... 

The starting material is produced by reacting propiophenone with bromine and then reacting the Qf-bromopropiophenone produced with 2-methylaminomethanol. 

Similar to 67, the oxanickelacycle 69 prepared from 3-hexyne, Ni(cod)2/bipy, and C02 also acted as a nucleophilic reagent. The reaction of 69 with p-tolyl disulfide took place at the Ni-C bond to give vinyl sulfide 70 in 53% yield after esterification (Scheme 23).37 In the case of 2-bromopropiophenone as an electrophile, the cycloadduct 71 was obtained in 47% yield after acidic workup. 

Bupropion The synthesis of bupropion, I-3(-chlorophenyl)-2-[(I,I-dimethyIethyl)amino]-I-propanone (7.3.5), begins with the reaction of 3-chlorobenzonitriIe, with ethylmagnesium bromide to give 3-chloropropiophenone (7.3.3). Brominating this with bromine gives 3-chloro-a-bromopropiophenone (7.3.4), which on reaction with tert-butylamine gives bupropion (7.3.5) [54-58]. 

Diethylpropion Diethylpropion, l-phenyl-2-diethylaminopropanon (8.3.6), is synthesized by the bromination of propiophenone into a-bromopropiophenone (8.3.5) and the subsequent substitution of the bromine atom with a diethylamino group [25,26]. 

It is synthesized from 4-benzyloxypropiophenone, which undergoes bromination into 4-benzyloxy-a-bromopropiophenone (11.1.17). This is reacted with 2-(4-benzy-loxyphenyl)ethylamine, forming an intermediate product (11.1.18), which undergoes fnrther debenzylation by hydrogen nsing a palladium catalyst, giving ritodrine (11.1.19) [24,25]. 

The Tschitschibabin reaction represents the most versatile way to substituted indolizines. It fails only in the case of indolizines bearing no substituents on the five-membered ring. Usually the intermediate quaternary salt (108) is isolated, but in some cases a one-pot reaction has been performed. The cyclization of (108) normally proceeds directly to the indolizine (110). A carbinol intermediate (109), however, has been isolated from the reaction of 2-picoline and 2-bromopropiophenone in the absence of a solvent (73JCS(P1)2595). 

Although the cyclization normally proceeds directly to the indolizine, the carbinol intermediate (1) was the product isolated when 2-picoline and 2-bromopropiophenone were heated together in the absence of a solvent.9 Usually the intermediate quaternary salt is isolated, but in some cases this is unnecessary and only the final product is isolated10,11 e.g., the base 2 in Eq. (1). A similar reaction, using an a-bromoester... 

Standard Heck coupling of o-bromopropiophenone with propyne proceeds in 72% yield. Deprotonation of the product thus formed with KHMDS in toluene at -78°C followed by heating at 75°C for one hour gave 3-methyl-1-naphthol in 74% yield after acidic work-up and distillation. This approach has proved to be general and efficient for the preparation of a variety of 3-alkyl-1 -naphthols. 

The p-benzoxy-a-bromopropiophenone and l-phenyl-3-amino-butane were heating for an hour on the water bath in the absence of solvents. A solid crystalline cake was obtained. After being extracted with boiling acetic acid, the hydrobromide of l-(p-hydroxyphenyl)-2-(p-phenylbutylamino)propanone-l was obtained. 

In methylene chloride (3 L) was dissolved m-chloropropiophenone (698.0 g 4.15 mole). The solution was stirred with charcoal (Darco) and magnesium sulfate for 2 h and filtered. To it was added with stirring (662.0 g) of bromine in methylene chloride (1 L). When the bromine color had faded completely, the solvent was evaporated in vacuum and m-chloro-a-bromopropiophenone was obtained as oil. 

The m-chloro-a-bromopropiophenone was dissolved in acetonitrile (1300 ml). To this, t-butylamine (733.0 g) in acetonitrile (1300 ml) was added while keeping the temperature below 32°C. The reaction mixture was allowed to stand over night. It was then partitioned between water (4200 ml) and ether (2700 ml). The aqueous layer was extracted with a further portion of ether (1300 ml). The combined ethereal layers were then washed with water (4200 ml) to which hydrochloric acid was added until the pH of the aqueous layer was 9. The aqueous layer was separated and washed with ether (500 ml) and then discarded. The combined ethereal layers were then stirred with ice (560.0 g) and concentrated hydrochloric acid (324 ml). The ethereal layer was separated and again washed with water (200 ml) and concentrated hydrochloric acid (50 ml). These last two acid layers were combined and concentrated in vacuum until crystals appeared. The solution was then chilled to 5°C and filtered. The product was sucked dry, washed with acetone and recrystallized from a mixture of isopropanol (3 L) and absolute ethanol (800 ml). The DL-m-chloro-a-t-butylaminopropiophenone hydrochloride so was obtained, melting point 233°-234°C. 

Acetylhydrazino)pyridine Hydrogen bromide 2-Bromopropiophenone Bromine... 

Bromopyridine Butyl lithium co-Dimethylamino-4 -bromopropiophenone Sulfuric acid ... 

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