Lewis base catalyzed trialkylsilylcyanide additions to cyclic 2-fluoroketones: nucleophile directed access to both cis- and trans-stereoisomers. Issue 20 (18th May 2016)

• Record Type: Journal Article
• Authors: Brawley, Kayla K.; Davis, Todd A.
• Is Part Of: Tetrahedron letters. Volume 57:Issue 20(2016)
• Page Start: 2161
• Page End: 2164
• Publication Date: 2016-05-18
• Subjects: Fluorine -- Lewis base catalysis -- Stereoselective synthesis; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tetlet.2016.03.112
• Languages: English
• ISSNs: 0040-4039

Abstract

Graphical abstract: Highlights: Lewis base catalyzed nucleophilic organosilane addition to fluorinated carbonyls. Nucleophilic organosilane (TBSCN or TMSCN) directs stereochemical outcome. Stereoselective nucleophilic additions to fluorinated carbonyls. Abstract: An efficient method for the Lewis base-catalyzed addition of trialkylorganosilanes (TMSCN & TBSCN) to cyclic 2-fluoroketones has been developed producing the TMS- or TBS-protected cyanohydrins in good yields and diastereoselectivity. The Lewis base, solvent, and trialkylorganosilane have a dramatic effect on the reaction time and stereoselectivity for these reactions. TMSCN reacted the fastest using DIPEA as the Lewis base, and favored the cis product (up to 22:1), whereas methoxide-catalyzed reactions with TBSCN yielded the trans stereoisomer (up to 18:1).