Synthesis, isolation and characterization of cationic gold(<scp>i</scp>) N-heterocyclic carbene (NHC) complexes
作者:Pierre de Frémont、Edwin D. Stevens、Manuel R. Fructos、M. Mar Díaz-Requejo、Pedro J. Pérez、Steven P. Nolan
DOI:10.1039/b601547f
日期:——
A number of cationic gold(I) complexes have been synthesized and found to be stabilized by the use of N-heterocyclic carbene ligands. These species are often employed as in situ-generated reactive intermediates in gold catalyzed organic transformations. An isolated, well-defined species was tested in gold-mediated carbene transfer reactions from ethyl diazoacetate.
Expedient Syntheses of Neutral and Cationic Au(I)–NHC Complexes
作者:Richard M. P. Veenboer、Danila Gasperini、Fady Nahra、David B. Cordes、Alexandra M. Z. Slawin、Catherine S. J. Cazin、Steven P. Nolan
DOI:10.1021/acs.organomet.7b00622
日期:2017.9.25
The synthesis and isolation of gold(I) precatalysts often requires the generation of several isolable intermediates as well as numerous purification steps. New protocols for the expedient synthesis of neutral [Au(OH)(NHC)] and [Au(CH2COCH3)(NHC)] species from [AuCl(NHC)] or [AuCl(DMS)] precursors bearing a variety of N-heterocyclic carbene (NHC) ligands are presented. These methods can be employed
Chiral Au<sup>I</sup>
- and Au<sup>III</sup>
-Isothiourea Complexes: Synthesis, Characterization and Application
作者:Danila Gasperini、Mark D. Greenhalgh、Rehan Imad、Shezaib Siddiqui、Anum Malik、Fizza Arshad、Muhammad Iqbal Choudhary、Abdullah M. Al-Majid、David B. Cordes、Alexandra M. Z. Slawin、Steven P. Nolan、Andrew D. Smith
DOI:10.1002/chem.201804653
日期:2019.1.18
organocatalysis and goldcatalysis, the formation of gold‐isothiourea complexes was observed. These novel gold complexes were formed in high yield and were found to be air‐ and moisture stable. A series of neutral and cationic chiral gold(I) and gold(III) complexes bearing enantiopure isothiourea ligands was therefore synthesized and fully characterized. The steric and electronicproperties of the isothiourea
Rational Design of a Gold Carbene Precursor Complex for a Catalytic Cyclopropanation Reaction
作者:David H. Ringger、Peter Chen
DOI:10.1002/anie.201209569
日期:2013.4.22
solution‐phase chemistry: A gold(I) carbeneprecursorcomplex has been developed and investigated for catalyticcyclopropanation. Formation of the carbene intermediate was first probed by mass spectrometry, followed by cyclopropanation of p‐methoxystyrene in solution. The imidazolylidene leaving group serves as a base generated in situ that is necessary in the putative catalytic cycle.
Highly active gold-based catalyst for the reaction of benzaldehyde with ethyl diazoacetate
作者:Manuel R. Fructos、M. Mar Díaz-Requejo、Pedro J. Pérez
DOI:10.1039/b908233f
日期:——
The gold complex [IPrAu(NCMe)]BF(4) catalyzes the reaction of ethyldiazoacetate with benzaldehyde to give mixtures of ethyl 3-oxo-3-phenylpropanoate and ethyl 3-hydroxy-2-phenylacrylate in the first example of a group 11 metal-based catalyst for this transformation; the catalyst activity is improved by a factor of 2500 compared to those of previously reported iron-based catalysts.