title: A highly diastereoselective pinacol coupling reaction of aldehydes and ketones using low-valence niobium generated from Nb(V).
abstract: A simple method for the diastereoselective synthesis of racemic 1,2-diol mediated by low-valence niobium generated in situ is described. A 1,4-dioxane-toluene solvent system was found to be essential to achieve higher selectivities and to prevent other reactions of pinacols, such as deoxygenation and acetal formation. Aromatic aldehydes and ketones were converted to the corresponding pinacols with up to 97 and 85% de, respectively.
authors.affiliation: Graduate School of Pharmaceutical Sciences, Chiba University, Chiba, Japan. arai@p.chiba-u.ac.jp
authors.forename: Shigeru
authors.initials: S
authors.lastname: Arai
authors.forename: Yukinori
authors.initials: Y
authors.lastname: Sudo
authors.forename: Atsushi
authors.initials: A
authors.lastname: Nishida
mesh_terms: D000447:Aldehydes / Q000737:chemistry*; D006841:Hydrocarbons, Aromatic / Q000737:chemistry*; D007659:Ketones / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D009556:Niobium / Q000737:chemistry*; D013237:Stereoisomerism
chemical_list: D000447:Aldehydes; D006841:Hydrocarbons, Aromatic; D007659:Ketones; D009556:Niobium