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From tosylhydrazones and methyllithium

Olefins, conversion to alcohols, 53, 94 from tosylhydrazones and methyllithium, 51, 69 hydroboration-oxidation of,... [Pg.62]

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]

The dry tosylhydrazone (20 g, 45.5 mmol) is dissolved in 750 ml of 1,2-dimethoxyethane (freshly distilled from lithium aluminum hydride) in a flame-dried 1 liter round bottom flask fitted with a 240 ml addition funnel, a drierite tube and a magnetic stirrer. A 2.05 M ether solution of methyllithium (130 ml, Alfa Inorganics, Inc.—Caution to avoid the mineral oil impurity the methyllithium solution is decanted from a cold solution which contains a precipitate) is placed in the dropping funnel and added over a 60 min period. The temperature of the reaction mixture increases to ca. 35° during the addition however, no cooling precautions are required. The highly colored reaction mixture is stirred for 7 hr and then poured into 1.5 liters of ice water. The flocculent precipitate is digested for 12 hr at room temperature to speed the filtration. After filtration the filter cake is washed with 500 ml water and dried under vacuum at 50° for several hr. The androsta-5,16-dien-3l5-ol is obtained in ca. 70% yield after recrystallization from methanol mp 138-139°. [Pg.33]

The 1,2-carbonyl transposition takes place through the enJo-epoxide 18 easily prepared through the tosylhydrazone 16, followed by regioselective cleavage to the less substituted double bond (17) with 2 equivalents of methyllithium [4] and epoxidation with MCPBA in chloroform from the more accesible convex face of the decalin system. [Pg.357]


See other pages where From tosylhydrazones and methyllithium is mentioned: [Pg.75]    [Pg.354]    [Pg.356]    [Pg.186]    [Pg.187]    [Pg.346]    [Pg.198]    [Pg.195]   
See also in sourсe #XX -- [ Pg.51 , Pg.69 ]




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