Simple activation by acid of latent Ru-NHC-based metathesis initiators bearing 8-quinolinolate co-ligands

• Julia Wappel,
• Roland C. Fischer,
• Luigi Cavallo,
• Christian Slugovc and
• Albert Poater

Beilstein J. Org. Chem. 2016, 12, 154–165, doi:10.3762/bjoc.12.17

• pressure [10]. Such kind of regulation of the catalysts activity does not only comprise a switching on of a particular feature but also the switching off of this feature upon another (different) stimulus. A simpler but related concept is to turn a latent catalyst [11] or initiator (i.e., ideally a

New aryloxybenzylidene ruthenium chelates – synthesis, reactivity and catalytic performance in ROMP

• Patrycja Żak,
• Szymon Rogalski,
• Mariusz Majchrzak,
• Maciej Kubicki and
• Cezary Pietraszuk

Beilstein J. Org. Chem. 2015, 11, 1910–1916, doi:10.3762/bjoc.11.206

• Grubbs catalysts bearing a triphenylphosphine ligand (or its para-substituted analogues) by metathesis exchange with substituted 2-vinylphenols. The complexes behave like a latent catalyst and are characterized by an improved catalytic behaviour as compared to that of the known analogues, i.e., they

• . Coordination motif of latent catalyst of olefin metathesis in which alkylidene ligand is bound to the heteroatom X, acting as an anionic ligand. Known latent catalysts of olefin metathesis in which alkylidene ligands are bound to a heteroatom, acting as an anionic ligand. Selected, known aryloxybenzylidene

Latent ruthenium–indenylidene catalysts bearing a N-heterocyclic carbene and a bidentate picolinate ligand

• Thibault E. Schmid,
• Florian Modicom,
• Adrien Dumas,
• Etienne Borré,
• Loic Toupet,
• Olivier Baslé and
• Marc Mauduit

Beilstein J. Org. Chem. 2015, 11, 1541–1546, doi:10.3762/bjoc.11.169

• . Keywords: latent catalyst; olefin metathesis; picolinate ligand; ruthenium indenylidene; Introduction Olefin metathesis has witnessed tremendous development in the last decades and has emerged as a powerful tool with dramatic impact on both organic chemistry and materials science [1][2]. Intensive

• handle and to operate (Figure 2). Consistent with its stability in solution, the latent catalyst 4a appeared totally inactive at room temperature (<1% conversion after 24 h at 297 K), while catalytic activity was observed in the RCM of diethyl diallylmalonate (DEDAM) after addition of TFA. Several acid

Advancements in the mechanistic understanding of the copper-catalyzed azide–alkyne cycloaddition

• Regina Berg and
• Bernd F. Straub

Beilstein J. Org. Chem. 2013, 9, 2715–2750, doi:10.3762/bjoc.9.308

• room temperature. However, in organic solvents such as THF, dichloromethane or tert-butanol, only poor conversions were observed with these [(NHC)CuX] catalysts. Nolan et al. also report on the possibility of using [(SIPr)CuCl] as a latent catalyst [148]. With DMSO as solvent, complex [(SIPr)CuCl] (2

• mol %) does not facilitate the cycloaddition reaction of benzyl azide and phenylacetylene within one week. However, the latent catalyst could be activated by adding water and heating the reaction mixture to 60 °C for one hour, whereupon 99% conversion was observed. In 2009, Gautier et al. reported

The catalytic performance of Ru–NHC alkylidene complexes: PCy₃ versus pyridine as the dissociating ligand

• Stefan Krehl,
• Diana Geißler,
• Sylvia Hauke,
• Oliver Kunz,
• Lucia Staude and
• Bernd Schmidt

Beilstein J. Org. Chem. 2010, 6, 1188–1198, doi:10.3762/bjoc.6.136

• activity of these pyridine-NHC complexes. They were found to initiate ring opening metathesis polymerization reactions very rapidly [30][31] and show a certain preference for cross metathesis [32][33][34][35]. If the pyridine ring is attached to the alkylidene ligand [36], a latent catalyst results which