The air-stable chiral diphosphine chelate ligand R,R-qinoxP (L; 2,3-bis(tert-butylmethylphosphino)quinoxaline) as developed by Imamoto et al. (2005). L was used to obtain the crystallog. characterized complexes (L)PtCl2 (1), (L)PdCl2 (2), and (L)Re(CO)3Cl (3). Coordination occurs via the P donor atoms, as indicated by crystal structures and NMR studies; the quinoxaline N donors do not participate in any coordination to the metals. The stereochem. arrangements obsd. illustrate the enantioselectivity reported for catalysis involving complexes of L. Electron acceptance by the quinoxaline heterocycle is responsible not only for the improved stability of L toward air but also for rather facile redn. of the complexes to the persistent radical anions 1·-and 3·- In contrast, the redn. to 2·- proceeds irreversibly even at 243 K in the absence of excess chloride. EPR, UV-vis, and IR spectroelectrochem. was used, when possible, to establish the spin location in the quinoxaline p system with rather small contributions from the metals or the P nuclei. on SciFinder(R)
%0 Journal Article
%1 Das.2008
%A Das, Atanu Kumar
%A Bulak, Ece
%A Sarkar, Biprajit
%A Lissner, Falk
%A Schleid, Thomas
%A Niemeyer, Mark
%A Fiedler, Jan
%A Kaim, Wolfgang.
%D 2008
%J Organometallics
%K carbonyl complex complex;electrooxidn complex;electroredn complex;palladium crystal diphosphinoquinoxaline group platinum prepn structure structure;platinum structure;rhenium
%N 2
%P 218--223
%R 10.1021/om700755y
%T Structures and redox properties of metal complexes of the electron-deficient diphosphine chelate ligand R,R-quinoxP
%V 27
%X The air-stable chiral diphosphine chelate ligand R,R-qinoxP (L; 2,3-bis(tert-butylmethylphosphino)quinoxaline) as developed by Imamoto et al. (2005). L was used to obtain the crystallog. characterized complexes (L)PtCl2 (1), (L)PdCl2 (2), and (L)Re(CO)3Cl (3). Coordination occurs via the P donor atoms, as indicated by crystal structures and NMR studies; the quinoxaline N donors do not participate in any coordination to the metals. The stereochem. arrangements obsd. illustrate the enantioselectivity reported for catalysis involving complexes of L. Electron acceptance by the quinoxaline heterocycle is responsible not only for the improved stability of L toward air but also for rather facile redn. of the complexes to the persistent radical anions 1·-and 3·- In contrast, the redn. to 2·- proceeds irreversibly even at 243 K in the absence of excess chloride. EPR, UV-vis, and IR spectroelectrochem. was used, when possible, to establish the spin location in the quinoxaline p system with rather small contributions from the metals or the P nuclei. on SciFinder(R)
@article{Das.2008,
abstract = {The air-stable chiral diphosphine chelate ligand R,R-qinoxP (L; 2,3-bis(tert-butylmethylphosphino)quinoxaline) as developed by Imamoto et al. (2005). L was used to obtain the crystallog. characterized complexes (L)PtCl2 (1), (L)PdCl2 (2), and (L)Re(CO)3Cl (3). Coordination occurs via the P donor atoms, as indicated by crystal structures and NMR studies; the quinoxaline N donors do not participate in any coordination to the metals. The stereochem. arrangements obsd. illustrate the enantioselectivity reported for catalysis involving complexes of L. Electron acceptance by the quinoxaline heterocycle is responsible not only for the improved stability of L toward air but also for rather facile redn. of the complexes to the persistent radical anions 1·-and 3·- In contrast, the redn. to 2·- proceeds irreversibly even at 243 K in the absence of excess chloride. EPR, UV-vis, and IR spectroelectrochem. was used, when possible, to establish the spin location in the quinoxaline \textgreek{p} system with rather small contributions from the metals or the P nuclei. [on SciFinder(R)]},
added-at = {2019-07-15T13:41:23.000+0200},
author = {Das, Atanu Kumar and Bulak, Ece and Sarkar, Biprajit and Lissner, Falk and Schleid, Thomas and Niemeyer, Mark and Fiedler, Jan and Kaim, Wolfgang.},
biburl = {https://puma.ub.uni-stuttgart.de/bibtex/279cdb9a98a8b1b6241ccb64026794c8b/b_schwederski},
doi = {10.1021/om700755y},
interhash = {9917f8ec8515ccfa875cb20958263a80},
intrahash = {79cdb9a98a8b1b6241ccb64026794c8b},
issn = {0276-7333},
journal = {Organometallics},
keywords = {carbonyl complex complex;electrooxidn complex;electroredn complex;palladium crystal diphosphinoquinoxaline group platinum prepn structure structure;platinum structure;rhenium},
number = 2,
pages = {218--223},
timestamp = {2019-07-15T11:42:10.000+0200},
title = {Structures and redox properties of metal complexes of the electron-deficient diphosphine chelate ligand R,R-quinoxP},
volume = 27,
year = 2008
}