Synthesis, Characterization, and Functionalization of 1‐Boraphenalenes. Issue 27 (6th June 2018)

• Record Type: Journal Article
• Authors: Kahan, Rachel J.; Crossley, Daniel L.; Cid, Jessica; Radcliffe, James E.; Ingleson, Michael J.
• Is Part Of: Angewandte Chemie international edition. Volume 57:Issue 27(2018)
• Page Start: 8084
• Page End: 8088
• Publication Date: 2018-06-06
• Subjects: aromaticity -- boron -- borylation -- phenalenyl -- polycyclic aromatic hydrocarbons; Chemistry -- Periodicals; 540
• DOI: 10.1002/anie.201803180
• Languages: English
• ISSNs: 1433-7851

Abstract

Abstract: 1‐Boraphenalenes have been synthesized by reaction of BBr3 with 1‐(aryl‐ethynyl)naphthalenes, 1‐ethynylnaphthalene, and 1‐(pent‐1‐yn‐1‐yl)naphthalene and they can be selectively functionalized at boron or carbon to form bench‐stable products. All of these 1‐boraphenalenes have LUMOs localized on the planar C12 B core that are closely comparable in character to isoelectronic phenalenyl cations. In contrast to the comparable LUMOs, the aromatic stabilization of the C5 B ring in 1‐boraphenalenes is dramatically lower than the C6 rings in phenalenyl cations. This is due to the occupied orbitals of π symmetry being less delocalised in the 1‐boraphenalenes. Abstract : Boron only : Naphthyl alkynes react with BBr3 to form phenalenes doped only with boron. All of the studied 1‐boraphenalenes have LUMOs localized on the C12 B core that are comparable to the isoelectronic phenalenyl cations.