Isolation of Stable Borepin Radicals and Anions. (5th April 2022)

• Record Type: Journal Article
• Authors: Hollister, Kimberly K.; Yang, Wenlong; Mondol, Ranajit; Wentz, Kelsie E.; Molino, Andrew; Kaur, Aishvaryadeep; Dickie, Diane A.; Frenking, Gernot; Pan, Sudip; Wilson, David J. D.; Gilliard, Robert J.
• Is Part Of: Angewandte Chemie. Volume 134:Number 23(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-04-05
• Subjects: Anions -- Borepin -- Boron -- Carbenes -- Radicals; Chemistry -- Periodicals; 540
• DOI: 10.1002/ange.202202516
• Languages: English
• ISSNs: 0044-8249

Abstract

Abstract: Borepin, a 7‐membered boron‐containing heterocycle, has become an emerging molecular platform for the development of new materials and optoelectronics. While electron‐deficient borepins are well‐established, reduced electron‐rich species have remained elusive. Herein we report the first isolable, crystalline borepin radical (2 a, 2 b ) and anion (3 a, 3 b ) complexes, which have been synthesized by potassium graphite (KC8 ) reduction of cyclic(alkyl)(amino) carbene‐dibenzo[b, d]borepin precursors. Borepin radicals and anions have been characterized by EPR or NMR, elemental analysis, X‐ray crystallography, and cyclic voltammetry. In addition, the bonding features have been investigated computationally using density functional theory. Abstract : The first examples of reduced borepins have been structurally characterized and offer new platforms for chemical reactivity.