0000000000042920
AUTHOR
Stephan Hartmann
showing 2 related works from this author
Aminoallenylidene complexes of ruthenium(II) from the regioselective addition of secondary amines to butatrienylidene intermediates: a combined exper…
2003
Aminoallenylidene complexes trans-[Cl(dppm)2RuC3(NRR )(CH3)] are obtained from the regioselective addition of secondary amines to trans-[Cl(dppm)2Ru C C C CH2] . Unsymmetrically substituted amines give rise to Z/E isomeric mixtures. Dynamic 31P NMR spectroscopy gave an energy barrier of about 85 kJ mol 1 for rotation around the CN-bond pointing to a large contribution of the iminium alkynyl resonance form trans-[Cl(dppm)2Ru–C C– C( NRR )(CH3)] . This is also indicated by the pronounced bond length alternation within the RuC3N-chain as is revealed by X-ray structure analysis of the Z isomer of the (benzylmethyl)methylamine derivative 2d. The issue of NR2 rotation was also addressed by DFT ca…
Five-Membered 2-Methylene-2,3-dihydro Heterocycles from Ruthenium Butatrienylidene Intermediates and 2-(Dimethylamino)methyl-Substituted Furans, Thio…
2003
Trapping of the primary butatrienylidene intermediate trans-[Cl(dppm) 2 Ru=C=C=C=CH 2 ] + with five-membered 2-(dimethylamino)methyl-substituted heterocycles provides an easy and efficient route to aminoallenylidene complexes with appended 2-methylene-2,3-dihydrofuran, -thiophene, or -selenophene moieties. Upon warming or acid catalysis isomerization to the aromatic 2-methylated isomers is observed.