Hexanoyl chloride

Nonanedione, another 1,3-difunctional target molecule, may be obtained from the reaction of hexanoyl chloride with acetonide anion (disconnection 1). The 2,4-dioxo substitution pattern, however, is already present in inexpensive, symmetrical acetylacetone (2,4-pentanedione). Disconnection 2 would therefore offer a tempting alternative. A problem arises because of the acidity of protons at C-3 of acetylacetone. This, however, would probably not be a serious obstacle if one produces the dianion with strong base, since the strongly basic terminal carbanion would be a much more reactive nucleophile than the central one (K.G. Hampton, 1973 see p. 9f.). 

A mixture consisting of the step 1 product (30 g), 200 ml THF, and 48 ml triethyl-amine was cooled to 0°C and then treated with the dropwise addition of 6-bromo-hexanoyl chloride (36.5 g) dissolved in 150 ml THF over 25 minutes. After stirring for 2 hours the reaction was partitioned between water and diethyl ether and the organic component washed with dilute hydrochloric acid, water, dried, filtered, and concentrated. The residue was crystallized from isopropyl alcohol and the product isolated. 

The reaction of 1,2,5-dithiazepine 124 with hexanoyl chloride in the presence of sodium hydroxide led to the formation of l-hexanoyl-6,6,9,9-tetramethyIhexahydroimidazo[2,l-<7][l,2,5]dithiazepine 125 in 70% yield (Scheme 29) <1996AJC239>. The subsequent reaction of 124 with 2-(triphenylmethylthio)ethanoic acid in the presence of... 

Cognate preparations. Hexanoyl chloride. Place 58 g (62 ml, 0.5 mol) of hexa-noic acid in the flask, heat on a water bath and add 72 g (43 ml, 0.6 mol) of redistilled thionyl chloride during 45 minutes shake the flask from time to time to ensure mixing. Reflux for 30 minutes and isolate the hexanoyl chloride by distillation, b.p. 150-155 °C. The yield is 56 g (83%). 

Isovaleryl chloride (3-methylbutanoyl chloride). Use 34 g (0.4 mol) of isovaleric acid and 47 g (0.5 mol) of thionyl chloride. Proceed as for hexanoyl chloride the yield of isovaleryl chloride is 36 g (76%), b.p. 114-115°C, after distillation through a Vigreux column. 

Place 125 ml of concentrated ammonia solution (dO.88) in a 600-ml beaker and surround the latter with crushed ice. Stir the ammonia solution mechanically, and introduce 56 g (0.42 mol) of hexanoyl chloride (Expt 5.138) slowly by means of a suitably supported separatory funnel. The rate of addition must be adjusted so that no white fumes are lost. The amide separates immediately. Allow to stand in the ice-water for 15 minutes after all the acid chloride has been introduced. Filter off the amide at the pump use the filtrate to assist the transfer of any amide remaining in the beaker to the filter (1). Spread the amide on sheets of filter or drying paper to dry in the air. The crude hexanamide (30 g, 63%) has m.p. 98-99 °C and is sufficiently pure for conversion into the nitrile (Expt 5.160) (2). Recrystallise a small quantity of the amide by dissolving it in the minimum volume of hot water and allowing the solution to cool dry on filter paper in the air. Pure hexanamide has m.p. 

Solamine (159) was found to be the principal component of Cyphoman-dra betacea. By treatment of solamine with n-hexanoyl chloride, the second component of the same plant was formed, which was also hydrolyzed to form -hexanoic acid and solamine (120). Solaurethine (163), an alkaloidal component of another plant in the Solanaceae, was obtained by treatment of solamine (159) with ethyl chloroformate (121). 

Note 11). The residual activated magnesium is rinsed once with 200 mL of dry diethyl ether, and the supernatant layer is transferred via cannula to the copper bromide-dimethyl sulfide slurry (Note 12). The reaction mixture is slowly warmed to -10°C, and then 16.78 g (17.42 mL, 125 mmol) of hexanoyl chloride is added dropwise via syringe after which the reaction mixture is warmed to room temperature. After stirring for 3 hr, the reaction mixture is filtered through a 75-g layer of Celite 545 (Note 13) and the filter cake rinsed with three 100-mL portions of diethyl ether. Concentration of the filtrate under reduced pressure yields the a-silyl ketone which is utilized without further purification (Note 14). 

Lithium wire (3.2 mm diam.), carbon tetrachloride, triphenylphosphine, MgBrEtaO, copper bromide-dimethyl sulfide complex, hexanoyl chloride, methyllithium, p-toluenesulfonic acid monohydrate, potassium hydride, and 18-crown-6 were purchased from Aldrich Chemical Company, Inc. and used without further purification. 

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