CHELATION ISOMERISM IN (ALLYLAMINO)CARBENE COMPLEXES AND ITS IMPACT ON STEREOSELECTION - A STUDY OF COORDINATION EQUILIBRIUM BY DYNAMIC HPLC

Authors
SCHICK U JORDI L RICART S VECIANA J DOTZ KH MORETO JM
Citation
U. Schick et al., CHELATION ISOMERISM IN (ALLYLAMINO)CARBENE COMPLEXES AND ITS IMPACT ON STEREOSELECTION - A STUDY OF COORDINATION EQUILIBRIUM BY DYNAMIC HPLC, Journal of the American Chemical Society, 120(10), 1998, pp. 2283-2289
Citations number
45
Categorie Soggetti
Chemistry
Journal title
Journal of the American Chemical Society → ACNP
ISSN journal
00027863
Volume
120
Issue
10
Year of publication
1998
Pages
2283 - 2289
Database
ISI
SICI code
0002-7863(1998)120:10<2283:CII(CA>2.0.ZU;2-Q
Abstract
A study related to isomerism brought about by the two different chelat ion modes of the residual double bond resulting from the intramolecula r Pauson-Khand reaction in [(diallylamino) alkynylcarbene] tungsten co mplexes was undertaken. The presence of a stereogenic center on the ca rbene ligand in the cycloadduct caused a clear difference in energy be tween the two diastereomeric forms resulting from alkene chelation. Th e energy barrier involved in their interconversion was determined by m eans of dynamic HPLC (D-HPLC) experiments, and its relative high value was related to the difficulty of the inversion at the nitrogen center due to structural rigidity.