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Cyclohexanone tosylhydrazone

Methylcyclohexene, from 2-methyl-cyclohexanone tosylhydrazone and methyllithium, 51,69 Methylenecyclopropanes, 50,30 Methyl iodide, with triphenyl phosphite and cyclohexanol, 51,45 with triphenyl phosphite and neopentyl alcohol, 51,44 METHYL ftrans-2-IODO-l-TETRA-LIN)CARBAMATE, 51,112 Methyl (frans-2-iodo-l-tetralin)carba-mate, with potassium hydroxide to give 1,2,3,4-tetrahydronaph-thalene(l,2)imine, 51,53 Methyllithium, with camphor tosylhydrazone to give 2-bomene, 51, 66... [Pg.79]

This procedure appears to be general for the preparation, without rearrangement, of lesser substituted olefins. 2-Methyl-cyclohexanone tosylhydrazone gives 3-methylcyclohexene (98% yield by gas chromatography analysis).8 Cholestan-6-one tosylhydrazone gives A6-cholestene (95% isolated yield), androstan-... [Pg.119]

A soln. of cyclohexanone tosylhydrazone in acetone heated 24 hrs. at 65° in a sealed glass tube cyclohexanone. Y 78%. F. e., also cleavage of phenyl-, 2,4-dinitrophenyl-hydrazones, and oximes, and a-perdeuteriated ketones with acetone d(j, s. S. R. Maynez, L. Pelavin, and G. Erker, J. Org. Chem. 40, 3302 (1975). [Pg.385]

Cyclohexanone tosylhydrazone treated 48 hrs. at room temp, with KCN in 2 10 acetic acid-methanol followed by addition of cold 2 N KOH 1-cyano-l-/ -... [Pg.34]

Another approach to (R)-(-)-phoracantholide I (245) used a ring enlargement of cyclohexanone (255) which had been alkylated with chiral synthon 256 (Scheme 14) [206]. Thus, compound 257 was prepared in 35% yield on a 7-g scale by alkylation of cyclohexanone with chiral 256. Cyclization with Am-berlyst A-15 provided enol ether 258 that was directly submitted to ruthenium tetroxide oxidation to give oxolactone 259 in a 47% yield. Reduction of the latter with catecholborane via its tosylhydrazone afforded (R)-(-)-phoracan-tholide I (245) in 31% yield. [Pg.227]

Cyclohexanone (202) was converted to compound (203) whose transformation to cyclohexanone (204) was accomplished in three steps. It underwent cyclialkylation with boron trifluoride etherate affording the cyclized product (205) (R=R,=OMe) in 64% yield along with naphthalene (206) (R=Ri= H,H). Compound (205) on heating under reflux with DDQ in benzene produced ketone (207) whose tosylhydrazone on treatment with sodium cyanoborohydride afforded reduced product (208). Deprotection of the aryl methyl ethers and oxidation with ceric ammonium nitrate led to the formation of miltirone (197). [Pg.215]

A two-step method to reduce a 0=0 to a CH2 group involves the conversion of a carbonyl group to a tosylhydrazone, followed by reduction with NaBH4. Draw a mechanism for the conversion of cyclohexanone to its tosylhydrazone, which is illustrated in the following equation. [Pg.820]

Ketones - Nitriles/ Ketones can be converted into nitriles by way of the tosyl-hydrazones. Thus the tosylhydrazone of cyclohexanone (I) on treatment with potassium cyanide in methanol acetic acid at room temperature followed by addition o( 2N... [Pg.512]

Nickon investigated the 1,2-hydrogen shifts in thermal and photic Bamford-Stevens reactions of cyclohexanones. Under eonditions known to favor the Shapiro reaction, tosylhydrazone 18a afforded the two expected alkenes 19 and 20 as well as an unexpected product (identified as 21) in a ratio of 15 60 25. Under conditions known to favor the Bamford-Stevens reaction, lithium salt 18b was subjected to thermolysis (neat, 170 °C) and also to photolysis (pentane suspension, -70 °C). Under both sets of conditions the three products 19, 20 and 21 were formed in approximately the same ratio (84 4 12 and 83 6 11), thus demonstrating the switching of major alkene product from 19 to 20 on moving from the Shapiro reaction to the Bamford-Stevens reaction. [Pg.645]

Six-membered Rings.—Cyclohexanones. Conversion of an alicyclic ketone into its corresponding methylene derivative is often necessary, but existing methods tend to require vigorous conditions. A mild method has been reported in which the ketone tosylhydrazone is treated with catechol borane in chloroform at 263 K and the reduction product decomposed with sodium acetate. Yields of 40—90% are claimed. [Pg.206]

Regeneration of the parent carbonyl compound from tosylhydrazones and 2,4-dinitrophenylhydrazones can be carried out in high yield using sodium nitrite in trifluoroacetic acid. Deprotection of tosylhydrazones using thallium triacetate in acetic add is also elficient. Oximes yield the carbonyl product on treatment with bromine in aqueous sodium bicarbonate, and the same conditions can be used to hydrolyse tosylhydrazones if HMPA is present. Aqueous nitric acid was found to be superior to both sulphuric and hydrochloric adds for the cleavage of the hydrazones (90) to the corresponding cyclohexanones. ... [Pg.74]


See other pages where Cyclohexanone tosylhydrazone is mentioned: [Pg.75]    [Pg.75]    [Pg.158]    [Pg.116]    [Pg.2806]    [Pg.715]   
See also in sourсe #XX -- [ Pg.820 ]




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