Reduction of aldehydes catalyzed by oxo-rhenium(V) complexes containing heterocyclic ligands. Issue 2 (8th January 2015)

• Record Type: Journal Article
• Authors: Bernando, Joana R.; Florindo, Pedro R.; Wolff, Mariusz; Machura, Barbara; Fernandes, Ana C.
• Is Part Of: Tetrahedron letters. Volume 56:Issue 2(2015)
• Page Start: 414
• Page End: 418
• Publication Date: 2015-01-08
• Subjects: Oxo-rhenium complexes -- Reduction -- Aldehydes -- Silanes; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tetlet.2014.11.119
• Languages: English
• ISSNs: 0040-4039

Abstract

Graphical abstract: Abstract: This work describes the catalytic activity of several oxo-rhenium complexes containing the heterocyclic ligands 2-(2-hydroxy-5-methylphenyl)benzotriazole (Hhmpbta), 2-(2-hydroxyphenyl)benzothiazole (Hhpbt), 2-(2-hydroxyphenyl)benzoxazole (Hhpbo), 2-(2-hydroxyphenyl)-1 H -benzimidazole (Hhpbi), isoquinoline-1-carboxylic acid (iqcH), and 4-methoxy-2-quinolinecarboxylic acid (mqcH) in the reduction of 4-nitrobenzaldehyde using phenylsilane as reducing agent. In general, all of the catalysts tested gave good to excellent yields of the 4-nitrobenzyl alcohol. Although, the best result was obtained with the catalytic system PhSiH3 /[ReOBr2 (hmpbta)(PPh3 )] (5 mol %). This system was also applied to the reduction of a large variety of aldehydes, producing the corresponding primary alcohols in good to excellent yields and good chemoselectivity.