Dialkylaluminum amides

EPOXIDES Alumina. r-Butyldimethyl-iodosilane. n-Butyllithium-Magnesium bromide. Cyclohexylisopropylamino-magnesium bromide. Dialkylaluminum amides. lodotrimethylsilane. Lithium l-a,a -dimethyldibenzylamide. Nafion-H. Organoaluminum compounds. Pyri-dinium chloride. Raney nickel. Tti-fluoroacetyl chloride, lrimethylsilyl-acctonitrile. Tris(phenylscleno)borane. Zinc iodide. 

AM1N0 ALCOHOLS AlkyUithium reagents. Dialkylaluminum amides. 

Asymmetric enolates of meso-ketones.1 The ketal 1, formed from 4-ethyl-cyclohexanone and (2R,4R)-2,4-pentanediol, when treated with triisobutylalu-minum in CH2C12 at -78° gives the enol ethers (S)-2 and (R)-2 in the ratio 6 1. Somewhat superior selectivity obtains by use of a dialkylaluminum amide such as 3.8... 

Chromium(III) chloride-Lithium aluminum hydride, 84 Dialkylaluminum amides, 206 Diazomethane-Alumina, 14 Dibromoalane, 237... 

The work on the AlR3-aeid amide catalyst system has its origin in the studies on the AlR3-ketone catalyst system (35). In the course of studies on the latter catalyst, we speculated that the dialkylaluminum monoenolate [X] might be superior to dialkylaluminum monoalcoholate [XI] as a stereospecific polymerization catalyst (35). Although the speculation on the active species of the AlR3-ketone catalyst system was disproved later by our more detailed studies, fortunately we could find out about the AlR3-acid amide catalyst system (35). 

The dialkylboranes and dialkylaluminums are also of value when partial reduction of an ester or amide is desired. The intermediates formed by the first hydride transfer are stable under the conditions of the reduction. Subsequent hydrolysis then provides the carbonyl compound at the aldehyde reduction stage. This method using diisobutylaluminum hydride has been particularly useful for reduction of esters to... 

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