4 research outputs found
Mapping the Basicity of Selected 3d and 4d Metal Nitrides: A DFT Study
Nitride complexes have been invoked
as catalysts and
intermediates
in a wide variety of transformations and are noted for their tunable
acid/base properties. A density functional theory study is reported
herein that maps the basicity of 3d and 4d transition metals that
routinely form nitride complexes: V, Cr, Mn, Nb, Mo, Tc, and Ru. Complexes
were gathered from the Cambridge Structural Database, and from the
free energy of protonation, the pKb(N)
of the nitride group was calculated to quantify the impact of metal
identity, oxidation state, coordination number, and supporting ligand
type upon metal-nitride basicity. In general, the basicity of transition
metal nitrides decreases from left to right across the 3d and 4d rows
and increases from 3d metals to their 4d congeners. Metal identity
and oxidation state primarily determine basicity trends; however,
supporting ligand types have a substantial impact on the basicity
range for a given metal. Synergism of these factors in determining
the overall pKb(N) values is discussed,
as are the implications for the catalytic reactivity of metal nitrides
Three Component Cascade Reaction of Cyclohexanones, Aryl Amines, and Benzoylmethylene Malonates: Cooperative Enamine-Brønsted Acid Approach to Tetrahydroindoles
A three-component
cascade reaction comprising cyclic ketones, arylamines,
and benzoylmethylene malonates has been developed to access 4,5,6,7-tetrahydro-1H-indoles. The reaction was achieved through cooperative
enamine-Brønsted catalysis in high yields with wide substrate
scopes. Mechanistic studies identified the role of the Brønsted
acid catalyst and revealed the formation of an imine intermediate,
which was confirmed by X-ray crystallography
Three Component Cascade Reaction of Cyclohexanones, Aryl Amines, and Benzoylmethylene Malonates: Cooperative Enamine-Brønsted Acid Approach to Tetrahydroindoles
A three-component
cascade reaction comprising cyclic ketones, arylamines,
and benzoylmethylene malonates has been developed to access 4,5,6,7-tetrahydro-1H-indoles. The reaction was achieved through cooperative
enamine-Brønsted catalysis in high yields with wide substrate
scopes. Mechanistic studies identified the role of the Brønsted
acid catalyst and revealed the formation of an imine intermediate,
which was confirmed by X-ray crystallography
Three Component Cascade Reaction of Cyclohexanones, Aryl Amines, and Benzoylmethylene Malonates: Cooperative Enamine-Brønsted Acid Approach to Tetrahydroindoles
A three-component
cascade reaction comprising cyclic ketones, arylamines,
and benzoylmethylene malonates has been developed to access 4,5,6,7-tetrahydro-1H-indoles. The reaction was achieved through cooperative
enamine-Brønsted catalysis in high yields with wide substrate
scopes. Mechanistic studies identified the role of the Brønsted
acid catalyst and revealed the formation of an imine intermediate,
which was confirmed by X-ray crystallography