Pinacol couplings of a series of aldehydes and ketones with SmI2/Sm/Me3SiCl in DME. Issue 33 (19th August 2015)

• Record Type: Journal Article
• Authors: Yoshimura, Aya; Saeki, Tomokazu; Nomoto, Akihiro; Ogawa, Akiya
• Is Part Of: Tetrahedron. Volume 71:Issue 33(2015)
• Page Start: 5347
• Page End: 5355
• Publication Date: 2015-08-19
• Subjects: Pinacol coupling -- Samarium diiodide -- Carbonyl compound -- Trimethylchlorosilane -- 1, 2-Dimethoxyethane; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tet.2015.06.007
• Languages: English
• ISSNs: 0040-4020

Abstract

Abstract: The pinacol coupling is one of the most significant methods to synthesize vic -diols. The combination of samarium diiodide (SmI2 ) and samarium metal successfully induces the selective pinacol couplings of not only aromatic aldehydes and ketones but also aliphatic ones in the presence of trimethylchlorosilane (Me3 SiCl) in 1, 2-dimethoxyethane (DME). DME is the most suitable solvent for the reduction system using SmI2 and Me3 SiCl. Me3 SiCl, a widely available additive, prevents the decomposition of the formed vic -diols, i.e., meso -isomers, and controls their stereochemistry. In particular, the pinacol couplings of sterically hindered aliphatic aldehydes and ketones proceed with excellent diastereoselectivities to afford dl -isomers in good yields. Graphical abstract: