Description

• Title:
  A photo-Smiles rearrangement: Mechanistic investigation of the formation of Blatter radical helicenes
• Creator:
  Kaszynski, Piotr
• Contributor:
  piotr.kaszynski@chemia.uni.lodz.pl;
  Kaszynski, Piotr
• Description:
  Photocyclization of 8-aryloxy-3-phenylbenzo[e]- [1,2,4]triazines leads to helicene radicals. Structural analysis of radicals leuco forms by two-dimensional correlation nuclear magnetic resonance methods demonstrated that the photo- cyclization involves a Smiles rearrangement and exclusive formation of a single rearranged product for all substrates. Density functional theory investigations indicate that the mechanism requires the T1 state with (n, π*) character localized on the benzo[e][1,2,4]triazine (BT) fragment and at least one occupied π molecular orbital (MO) localized on the aryloxy fragment with an energy that is higher than that of the n MO. This electronic structure is favorable for aryl-to-BT single-electron transfer and formation of a zwitterion, which undergoes an intramolecular polar cyclization followed by ring opening of the resulting spirooxazole. The proposed mechanism represents a new variation of photo-Smiles rearrangement and appears to be general for the photochemical formation of planar Blatter radicals.;
  Support for this project has been provided by National Science Center Grant 2020/38/A/ST4/00597.
• Object availability:
  free access
• Rights:
  ACS;
  Uznanie autorstwa 4.0 Międzynarodowe;
  http://creativecommons.org/licenses/by/4.0
• Date:
  2025.03.10;
  2025.01.10
• Type:
  Article
• Language:
  English
• Format:
  application/pdf
• Publisher:
  ACS
• Relation:
  The Journal of Organic Chemistry;;
  90
• Subject:
  Organic chemistry;
  synthesis;
  mechanism
• Identifier:
  0022-3263;
  http://hdl.handle.net/11089/54937 ;
  1520-6904;
  10.1039/JR9310003264
• Data provider:
  Repozytorium Uniwersytetu Łódzkiego
• Can I use it?:
  seek permission
• Type:
  image