Reduction using RedAl

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). 

He made both starting materials from esters of the corresponding aryl acetic acids 53 and 56 by reduction and substitution (in the case of the phosphonium salt). This gave added flexibility as either component can be used as the phosphonium salt 55 or the aldehyde 54. He used the unusual reducing agent REDAL [NaAlH2(0CH2CH20Me)2] instead of DIB AL to make the aldehyde 54. 

---