Butyryl chlorides, chloro

The initial series of major tranquilizers consists of alkylated derivatives of 4-aryl-4-hydroxypiperidines. Construction of this ring system is accomplished by a set of rather unusual reactions. Condensation of methylstyrenes with formaldehyde and ammonium chloride afford the corresponding hexahydro-1,3-oxazines (119). Heating these oxazines in the presence of acid leads to rearrangement with loss of water to the tetrahydropyridines. Scheme 1 shows a possible reaction pathway for these transformations. Addition of hydrogen bromide affords the expected 4-bromo compound (121). This last is easily displaced by water to lead to the desired alcohol (122) The side chain (123) is obtained by Friedel-Crafts acylation of p-fluorobenzene with 4-chloro-butyryl chloride. Alkylation of the appropriate arylpiperidinol with 123 affords the desired butyrophenone derivative. Thus,... 

Addition of a polarizing catalyst, e.g., I2, is recommended. Thus 2-chloro-propionyl or -butyryl chloride is prepared by passing dry Cl2 into the boiling acid chloride (30 g) containing a little (0.5 g) iodine until the theoretical increase in weight is achieved.538... 

Butyric acid, butyl ester. See Butyl butyrate Butyric acid, 4-((2-carboxyethyl) amino)-. See Carboxyethyl aminobutyric acid Butyric acid chloride. See Butyryl chloride Butyric acid, 4-((4-chloro-o-tolyl) oxy)-. See MCPB... 

Chloro-2-methylpropene C4H7CIO Butyryl chloride 2-Chloroethyl vinyl ether C4H7CIO2... 

Several observations indicate that this is reasonable. When a mixture of benzaldehyde and wo-butyryl chloride is treated with the organotin hydride, benzyl iro-butyrate is formed, but iro-butyl benzoate is not. Similarly when a mixture of benzoyl chloride and wo-butyraldehyde is reduced wo-butyl benzoate is formed, but benzyl iso-butyrate is not. Ethyl chloro-formate is reduced very slowly at 80° C by tri-n-butyltin hydride, but the addition of 2 mole-% of azobisisobutyronitrile leads to facile reduction. When triphenylacetyl chloride is reduced at 100° C with the same hydride the products include triphenylacetaldehyde, triphenylmethane, and carbon monoxide, but little, if any, j8,j8,j3-triphenylethyl triphenylacetate. The formation of carbon monoxide and triphenylmethane can be attributed to decarbonylation of the intermediate acyl radical to the more stable trityl radical, Eq. (61), which subsequently abstracts a hydrogen atom from the... 

Olefinic ketones have been obtained from the reaction of acyl chlorides or anhydrides with olefins using the conditions of the Friedel-Crafts reaction. The intermediate chloro ketones are oftentimes stable and must be treated with sodium bicarbonate or dimethylaniline to complete the de-hydrohalogenation. In this manner, 1-acetyl-1-cyclohexene (62%) ° and 1-butyryl-1-cyclohexene (60%) are prepared. 

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