Acetone catalytic hydrogenation

Introduction of a 16P-methyl group into the corticosteroid molecule was effected by a reaction (83) whereby a 16-dehydropregnenolone (62) was treated with dia2omethane to form the pyra2oline (75) which was decomposed with perchloric acid in acetone to give the 16-methylpregn-16-en-20-one derivative (76). Catalytic hydrogenation yielded the 16P-methyl intermediate (77), which was converted into... 

DIBK can be produced by the hydrogenation of phorone which, in turn, is produced by the acid-catalyzed aldol condensation of acetone. It is also a by-product in the manufacture of methyl isobutyl ketone. Diisobutyl ketone ( 1.37/kg, October 1994) is produced in the United States by Union Carbide (Institute, West Virginia) and Eastman (Kingsport, Teimessee) (47), and is mainly used as a coating solvent. Catalytic hydrogenation of diisobutyl ketone produces the alcohol 2,6-dimethyl-4-heptanol [108-82-7]. 

An improved version of the amine hydrolysis process involves catalytic hydrogenation of 1,3,5-triaitrobenzene or 2,4,6-triaitrobenzoic acid in acetone solvent (138). Acid hydrolysis of 2,4,6-triaminobenzoic acid has been improved by addition of copper catalyst and gives phlorogluciaol in 80% yield (139). 

In view of the unexpected effects of the C-2 and C-3 substituents on the reaction of C-4 sulfonates, it is worthwhile to point out the observations made with some 2,3-dideoxy derivatives. Treatment of ethyl 2,3-dideoxy-4,6-di-0-methylsulfonyl-D-ert/ hro-hexopyranoside (40) with sodium iodide and acetone at 115°C. caused the displacement of the C-6 mesylate group selectively to give 41. Catalytic hydrogenation then gave the corresponding ethyl 4-0-methylsulfonyl-2,3,6-trideoxy- -D-en/ /iro-hexoside in good overall yield (83%) (72). 

Myrcene, C10H16, is found in oil of bay leaves and is isomeric with jS-ocimene (Problem 14.48). It has an ultraviolet absorption at 226 nm and can be catalytically hydrogenated to yield 2( 6-dimethyloctane. On ozonolysis followed by zinc/acetic acid treatment, myrcene yields formaldehyde, acetone, and 2-oxopentanedial ... 

Ketals of acetone and cyclohexanone with methyl, butyl, isopropyl and cyclohexyl alcohols are hydrogenolyzed to ethers and alcohols by catalytic hydrogenation. While platinum and ruthenium are inactive and palladium only partly active, 5% rhodium on alumina proves to be the best catalyst which, in the presence of a mineral acid, converts the ketals to ethers and alcohols in yields of 70-100% [933]. 

BMrSbFe was used in the catalytic hydrogenation of pent-l-ene the rates were nearly five tunes higher than for the comparable homogeneous reaction in acetone (see table 6.6). 

Problem 18.47 What is the product of catalytic hydrogenation of (a) acetone oxime, b) propane-1,3-dinitrile, (c) propanal and methylamine M... 

Lawson KH, Nkosi B. Production of MIBKfrom acetone and hydrogen using catalytic distillation technology. U.S. Patent 6,008,416, Catalytic Distillation Technologies, 1999. 

We expected that the conformation of the acetonated derivatives 26 and 27 would be much more rigid than 24 to keep the half-chair form having the quasi-axidl amino group. Mild catalytic hydrogenation of 26 gave quantitatively die corresponding amino compound 27. 

One of the earliest reported preparations of the requisite glycosidation precursor 5-deoxy-l,2,3-tri-0-acetyl-p-D-ribofuranoside (17) was published by Kissman and Baker in 1957.23 D-Ribose was heated at reflux in a methanol/acetone mixture in the presence of concentrated HCI to provide methyl 2,3-O-isopropylidene-D-ribofuranosidc (21), which was in turn converted to the corresponding 5-O-mesyl ribofuranoside 22 with methanesulfonyl chloride in pyridine in 63% yield. The sulfonate moiety of 22 was then displaced with sodium iodide in refluxing DMF to provide 5-deoxy-5-iodo derivative 23 in 76% yield on a multigram scale. Reductive dehalogenation of 23 was accomplished under heterogeneous catalytic hydrogenation conditions to provide the reduced 2,3-0-protected intermediate 24 in 56% yield, which was subjected to hydrolysis conditions in... 

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