Federmann Patrick, Wagner Hannah K, Antoni Patrick W, Mörsdorf Jean-Marc, Pérez Lustres José Luis, Wadepohl Hubert, Motzkus Marcus, Ballmann Joachim
Anorganisch-Chemisches Institut , Universität Heidelberg , Im Neuenheimer Feld 276 , D-69120 Heidelberg , Germany.
Physikalisch-Chemisches Institut , Universität Heidelberg , Im Neuenheimer Feld 229 , D-69120 Heidelberg , Germany.
Org Lett. 2019 Apr 5;21(7):2033-2038. doi: 10.1021/acs.orglett.9b00161. Epub 2019 Mar 21.
The previously elusive diphosphadibenzo[ a, e]pentalene core skeleton was assembled via a surprisingly straightforward cyclization pathway starting from RP-substituted 2,2'-diphosphinotolanes (R = Ph, Pr). The resulting P-protected diylidic compounds 4 (R = Ph, Pr) were converted to the corresponding P-bridged ladder stilbenes via two consecutive oxidation steps: upon selective one-electron oxidation, the persistent radical monocations 5 (R = Ph, Pr) were obtained and further oxidized to afford the respective fluorescent and air-stable dications 6 (R = Ph, Pr).
