Redal hydride

In the fine chemical industry, reduction of carbonyl groups mainly relies on the use of complex metal hydrides sodium dihydrobis-(2-methoxyethoxy)-aluminate, commercialized as RedAl or Vitride is one of the most used (4). 

The effect of the catalyst chemical nature is demonstrated using two catalysts, sodium hydride, NaH, and sodium )is(2-metoxy-ethoxy)aluminium hydride, RedAl , which react with L6 giving rise to two lactamate anions with different nucleophilicity. The... 

Sodium bis(2-methoxyethoxy(aluminum hydride)) (Redal-H) is an excellent reagent for reducing propargylic alcohols to allylic alcohols. Reviews (a) Seyden-Penne, J. Reductions by the Alumino- and Borohydrides in organic Synthesis Wiley-VCH NewYork, 1997, 2" edition, (b) Mdlek, J. Org. React. 1985, 34, 1-317. 

DEAD Diethyl azodicarboxylate RedAl Sodium bis(2-methoxyethoxy)aluminum hydride... 

The mechanism of the aluminium hydride reductions with LiAlff4 or RedAl involve a tram hydroalumination helped by coordination of A1 to the triple bond and external nucleophilic attack. The regioselectivity of the hydroalumination is again determined by silicon the electrophilic A1 attacks the alkyne on the carbon bearing the silyl group (the ipso carbon). 

Unique properties of solubility and reactivity are encountered when certain functionalized alcohols interact with lithium aluminum hydride. Sodium bis(2-methoxyethoxy)aluminum hydride ( Redal ), for example, is soluble in benzene even at —70°. It is possible to reduce esters to aldehydes with this reagent ... 

Reduction with Redal (bismethoxyethoxyaluminum hydride) at 4° of tbe lactone 16 supplied the hemiacetal 17 which was 0-methylated and subjected again to Redal reduction, this time at 20°. The product was the secondary amine 18 which was A -methylated to the trans-fused rhoeadine analog 19 ° ... 

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