Preparation and reactions of 4-iodobutyl pinacolborate. Synthesis of substituted alkyl and aryl pinacolboronates via 4-iodobutyl pinacolborate utilizing tetrahydrofuran as the leaving group. Issue 23 (3rd June 2015)

• Record Type: Journal Article
• Authors: Murphy, Chris L.; Hall, Aaron; Roberts, Emily J.; Ryan, Matthew D.; Clary, Jacob W.; Singaram, Bakthan
• Is Part Of: Tetrahedron letters. Volume 56:Issue 23(2015)
• Page Start: 3032
• Page End: 3033
• Publication Date: 2015-06-03
• Subjects: Borate -- Boronate -- Grignard -- Barbier -- Ether cleavage; Chemistry, Organic -- Periodicals; 547.005
• DOI: 10.1016/j.tetlet.2014.12.033
• Languages: English
• ISSNs: 0040-4039

Abstract

Graphical abstract: Abstract: Iodine reacts with 4, 4, 5, 5-tetramethyl-1, 3, 2-dioxaborolane (HBpin), under ambient reaction conditions in THF, to form the iodoalkylborate species 2-(4-iodobutoxy)-4, 4, 5, 5-tetramethyl-1, 3, 2-dioxaborolane (4-IboxBpin). Apparently, one-half equivalent of I2 reacts with HBpin to form IBpin in pentanes, which in turn cleaves THF to form the 4-IboxBpin. Alkyl and aryl Grignard reagents, prepared under Barbier conditions, then react with 4-IboxBpin to form the corresponding alkyl and aryl pinacolboronates while reforming and liberating THF as the leaving group.