Acetyl chloride, acetic anhydride hydrolysis

Hydrolysis. 1,1,1-Trichloroethane heated with water at 75—160°C under pressure and in the presence of sulfuric acid or a metal chloride catalyst decomposes to acetyl chloride, acetic acid, or acetic anhydride (54). However, hydrolysis under normal use conditions proceeds slowly. The hydrolysis is 100—1000 times faster with trichloroethane dissolved in the water phase than vice versa. Refluxing 1,1,1-trichloroethane with ferric and gallium chloride... 

Cyclization of enone (9) in hexane with boron trifluorideetherate in presence of 1,2-ethanedithiol, followed by hydrolysis with mercury (II) chloride in acetonitrile, yielded the cis-isomer (10) (16%) and transisomer (11) (28%). Reduction of (10) with lithium aluminium hydride in tetrahydrofuran followed by acetylation with acetic anhydride and pyridine gave two epimeric acetates (12) (32%) and (13) (52%) whose configuration was determined by NMR spectroscopy. Oxidation of (12) with Jones reagent afforded ketone (14) which was converted to the a, 3-unsaturated ketone (15) by bromination with pyridinium tribromide in dichloromethane followed by dehydrobromination with lithium carbonate and lithium bromide in dimethylformamide. Ketone (15), on catalytic hydrogenation with Pd-C in the presence of perchloric acid, produced compound (16) (72%) and (14) (17%). The compound (16) was converted to alcohol (17) by reduction with lithium aluminium hydride. 

Hydrolysis of deferriferricrocin in 57% HI gives serine, glycine, alanine, ornithine and ammonia in the molar ratios 0.25 2.00 0.68 3.05 0.04 no alanine is found on hydrolysis in 6N HCI. Treatment with IN HCI at 100° for 15 min. gives substance with negative ferric chloride test. Re-acetylation with acetic anhydride and removal of O-acetyl affords a product with chromatographic properties of ferricrocin. 

Hydrogenation was carried out at O to minimize decarboxylation of the saturated 3-keto acid product 18. Mannich reaction proceeded with in situ decarboxylation to afford a-methylene ketone 19, which on Michael reaction with ketal 3 keto ester 20 -" yielded adduct 21. Saponification, B ring closure, and decarboxylation then led to ketalenone 23 in high yield, which was converted into ( + )-19-nortestosterone 24 and thence to ( + )-19-norandrostenedione 25 in 50% yield from 18 or 27% overall yield from 12. However, ketal hydrolysis, A ring closure, oxidation at C-17, and isomerization by the Roussel procedure (acetyl bromide-acetic anhydride in methylene chloride at 20°) should yield (-f )-estrone 26 efficiently. 

Acid anhydrides are more stable and less reactive than acyl chlorides Acetyl chlo ride for example undergoes hydrolysis about 100 000 times more rapidly than acetic anhydride at 25°C... 

These can be prepared as for the benzoates using either acetic anhydride with 3N NaOH or acetyl chloride in pyridine. They are hydrolysed as described for the benzoates. This hydrolysis can also be carried out with aqueous 10% NaOH solution, completion of hydrolysis being indicated by the complete dissolution of the acetate in the aqueous alkaline solution. On steam distillation, acetic acid also distils off but in these cases the phenols (see above) are invariably solids which can be filtered off and recrystallised. 

Hunter and Nelson (41 Mil) attempted the preparation of 4(5)-aminoimidazole (25 R = H) from its acetyl derivative (28 R = H, R1 = Me), which they obtained by reduction of 4(5)-nitroimidazole (27 R = H) with tin(II) chloride in acetic anhydride. The authors noted that hydrolysis of compound (28 R = H, R = Me) with aqueous acids resulted in fission of the imidazole ring and formation of acetic acid, formic acid, ammonia, and glycine. Base hydrolysis gave similar results (41 Mil), although a trace of 4(5)-aminoimidazole (25 R = H) was detected. 

Acetylacetone has been prepared by the reaction of acetyl chloride with aluminum chloride followed by hydrolysis,3 and by the condensation of acetone with ethyl acetate under the influence of sodium,4 sodamide,5 and sodium ethoxide,5-6-7 and by the reaction of acetone and acetic anhydride in the presence of boron trifluoride.8... 

The above procedure is essentially that of Ullmann and Bleier.2 2-Aminobenzophenone has also been prepared by reduction of 2-nitrobenzophenone,3 by the Hofmann reaction of the amide of o-benzoylbenzoic acid with sodium hypobromite,4 by the action of an excess of benzoyl chloride on aniline at 220°,6 and by hydrolysis of the acetyl derivative which is obtained by the action of phenylmagnesium bromide on 2-methyl-3,l,4-benzoxaz-4-one (from anthranilic acid and acetic anhydride).6 Various methods for the preparation of 2-aminobenzophenones have been summarized critically by Simpson, Atkinson, Schofield, and Stephenson.7... 

Hydrolysis of 439, 445-447 initiates desilylation to the corresponding imides 440, 448-450232,233 whereas treatment of 439 with acetyl chloride or acetic anhydride yields acetyliminotriphenylphosphorane (441)234,23S The reaction with... 

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