CONCERNING THE EFFECTS OF ADDED SALTS ON THE STEREOSELECTIVITY AND RATE OF ORGANOMETALLIC COMPOUND ADDITION TO KETONES

The addition of CH3Li to 4-tert-butylcyclohexanone in the presence of LiC104 increased the formation of the axial alcohol from 65 to 92% compared to the reaction in the absence of LiC104. This result was attributed to complexation of the ketone by LiC104 followed by the addition of CH3Li to the carbonyl group rather than by addition of a CH3Li-LiC104 complex directly to the uncomplexed ketone. To complete a more detailed investigation of this unusual result, other organometallic compounds, ketones, and salts were studied in a similar manner. In addition to CH3Li, t-BuLi, PhLi, (CH3)2Mg, and (CH3)3A1 were also allowed to react with 4-tert-butylcyclohexanone, 2-methylcyclohexanone 3, 3, 5-trimethylcyclohexanone, and norcamphor in the presence of equalmolar ratios of ten different salts in order to study their effect on the stereochemistry of the alcohol products. In addition to stereochemical effects, a major result of the reactions with RLi and R2Mg in the presence of LiC104 was a dramatic increase in the rate of reaction. © 1979, American Chemical Society. All rights reserved.