Aldiminium and 1,2,3-triazolium dithiocarboxylate zwitterions derived from cyclic (alkyl)(amino) and mesoionic carbenes

• Nedra Touj,
• François Mazars,
• Guillermo Zaragoza and
• Lionel Delaude

Beilstein J. Org. Chem. 2023, 19, 1947–1956, doi:10.3762/bjoc.19.145

• variety of small molecules and to bind strongly to metal centers, thereby affording very robust catalysts [9][10][11][12]. Another category of stable carbenes that has emerged in the new millennium is made of mesoionic compounds, for which no reasonable canonical resonance form can be drawn in the absence

NHC-catalysed highly selective aerobic oxidation of nonactivated aldehydes

• Lennart Möhlmann,
• Stefan Ludwig and
• Siegfried Blechert

Beilstein J. Org. Chem. 2013, 9, 602–607, doi:10.3762/bjoc.9.65

• , which is known to yield highly stable carbenes [19]. Using acetonitrile as solvent, 2 equivalents of water as a nucleophile, 2 mol % A, 1.1 equivalents of DBU and 20 mg/mmol mpg-C3N4, we obtained after 1 h under an O2 atmosphere, 85% conversion to the wanted acid. Next we tested different NHC-salts B–E

CAAC Boranes. Synthesis and characterization of cyclic (alkyl) (amino) carbene borane complexes from BF₃ and BH₃

• Julien Monot,
• Louis Fensterbank,
• Max Malacria,
• Emmanuel Lacôte,
• Steven J. Geib and
• Dennis P. Curran

Beilstein J. Org. Chem. 2010, 6, 709–712, doi:10.3762/bjoc.6.82

• carbenes; stable carbenes; Introduction Lewis acid/Lewis base complexes of N-heterocyclic carbenes and boranes (NHC–boranes) are readily prepared from NHC’s and boranes by direct complexation [1][2][3][4]. Unlike many other classes of Lewis base complexes of boranes with neutral molecules (ethers