Synthesis of
<i>N</i>
‐Heterocyclic Carbenes and Their Complexes by Chloronium Ion Abstraction from 2‐Chloroazolium Salts Using Electron‐Rich Phosphines
作者:Matthias D. Böhme、Tobias Eder、Maike B. Röthel、Patrick D. Dutschke、Lukas F. B. Wilm、F. Ekkehardt Hahn、Fabian Dielmann
DOI:10.1002/anie.202202190
日期:2022.7.11
Chloronium ion abstraction from 2-chloroimidazolium salts using tris(1,3-tert-butylimidazolin-2-ylidenamino)phosphine 1 rapidly affords the free N-heterocyclic carbenes (NHCs) and chlorophosphonium ions (1-Cl)+. The dechlorination can be used for the site-selective metallation of unsymmetric 2-chloroazole/2-chloroazolium bis-NHC precursors by phosphine-mediated chloronium ion abstraction followed by
Terminal methylene phosphonium ions: precursors for transient monosubstituted phosphinocarbenes
作者:Pawel Löwe、Marius A. Wünsche、Felix R. S. Purtscher、Jakob Gamper、Thomas S. Hofer、Lukas F. B. Wilm、Maike B. Röthel、Fabian Dielmann
DOI:10.1039/d3sc02899b
日期:——
Isolable singlet carbenes are among the most important tools in chemistry, but generally require the interaction of two substituents with the electron deficient carbon atom. We herein report a synthetic approach to monosubstituted phosphinocarbenes via deprotonation of hitherto unknown diprotic terminal methylene phosphonium ions. Two methylene phosphonium salts bearing bulky N-heterocyclic imine substituents