Reduction by Metal Alkoxyaluminum Hydrides. Part II. Carboxylic Acids and Derivatives, Nitrogen Compounds, and Sulfur Compounds

Málek, Jaroslav


In continuation of the previous review on reductions by metal alkoxyaluminum hydrides, this chapter is devoted to reductions of carboxylic acids and their derivatives, open-chain and heterocyclic nitrogen compounds, and open-chain and heterocyclic sulfur compounds by alkoxyaluminum hydrides, metal alkoxyaluminum hydrides, and chiral metal alkoxyaluminohydride complexes. Emphasis is placed on the scope, limitations, and the synthetic utility of metal alkoxyaluminum hydrides. Accepted views on reaction mechanisms are mentioned briefly. Discussion of alternative methods of reduction, particularly those using other metal hydrides or complex metal hydrides, is limited to examples of the most important transformations of functional groups; reducing properties of these hydrides and hydride reagents such as borane–dimethyl sulfide, amine boranes, haloboranes, organoboranes, sodium borohydride–pyridine, sodium borohydride–triphenyl borate, sodium borohydride—transition-metal complexes, potassium triisopropoxyborohydride, and sodium triacyloxyborohydrides have been reported in several papers and reviews. Monographs and reviews summarize reductions with metal alkoxyaluminum hydrides and asymmetric reductions with chiral lithium alkoxyaluminum hydrides and chiral boron reagents.