Diastereoselective Ullmann coupling to bishelicenes by surface topochemistry

0497883 - FZÚ 2019 RIV US eng J - Článek v odborném periodiku
Mairena, A. - Wackerlin, C. - Wienke, M. - Grenader, K. - Terfort, A. - Ernst, Karl-Heinz
Diastereoselective Ullmann coupling to bishelicenes by surface topochemistry.
Journal of the American Chemical Society. Roč. 140, č. 45 (2018), s. 15186-15189. ISSN 0002-7863. E-ISSN 1520-5126
Institucionální podpora: RVO:68378271
Klíčová slova: STM * on surface chemistry * Ullman coupling
Obor OECD: Physical chemistry
Impakt faktor: 14.695, rok: 2018

The comparison of the self-assembly 9,9′- bisheptahelicene on the Au(111) surface, studied with scanning tunneling microscopy, with the self-assembly of the same species obtained by on-surface synthesis via Ullmann coupling from 9-bromoheptahelicene reveals a diastereomeric excess for the (M,P)-meso-form of 50%. The stereoselectivity is explained by a topochemical effect, in which the surface-alignment of the starting material and the organometallic intermediate sterically favor the (M,P)-transition state over the homochiral transition states.
Trvalý link: http://hdl.handle.net/11104/0290351