TY - JOUR

T1 - Theoretical study of the reactivity of Rh(I) and Rh(III) Bis(isonitrile) complexes in cycloaddition reactions with nitrones

AU - Novikov, A. S.

AU - Dement'Ev, A. I.

AU - Medvedev, Yu N.

PY - 2013/1/1

Y1 - 2013/1/1

N2 - The mechanism of 1,3-dipolar cycloaddition of nitrone (CH 2=N(Me)O) to methylisonitrile coordinated to Rh(I) and Rh(III) in the [RhCl(PH3)(CNMe)2] and [RhCl3(PH 3)(CNMe)2] complexes has been studied by quantum-chemical methods. The molecular and electronic structures of the cycloaddition products, the nature of transition states, the mechanism of reactions, their kinetic and thermodynamic parameters, and the solvent effect have been described. The reactions occur via the concerted strongly asynchronous mechanism involving the formation of a five-membered cyclic transition state. The use of rhodium complexes as reagents leads to a noticeable decrease in the activation barriers of the processes under consideration and an increase in the magnitudes of energy effects of the reactions. It has been demonstrated that the Rh(III) complexes are better activators of the cycloaddition of nitrone to isonitrile than the Rh(I) complex. The calculations predict that in the case of the Rh(I) complexes, only one isonitrile ligand can be involved in cycloaddition of nitrone, whereas the use of the Rh(III) complexes enables the participation of both ligands. The solvation effects inhibit the reactions.

AB - The mechanism of 1,3-dipolar cycloaddition of nitrone (CH 2=N(Me)O) to methylisonitrile coordinated to Rh(I) and Rh(III) in the [RhCl(PH3)(CNMe)2] and [RhCl3(PH 3)(CNMe)2] complexes has been studied by quantum-chemical methods. The molecular and electronic structures of the cycloaddition products, the nature of transition states, the mechanism of reactions, their kinetic and thermodynamic parameters, and the solvent effect have been described. The reactions occur via the concerted strongly asynchronous mechanism involving the formation of a five-membered cyclic transition state. The use of rhodium complexes as reagents leads to a noticeable decrease in the activation barriers of the processes under consideration and an increase in the magnitudes of energy effects of the reactions. It has been demonstrated that the Rh(III) complexes are better activators of the cycloaddition of nitrone to isonitrile than the Rh(I) complex. The calculations predict that in the case of the Rh(I) complexes, only one isonitrile ligand can be involved in cycloaddition of nitrone, whereas the use of the Rh(III) complexes enables the participation of both ligands. The solvation effects inhibit the reactions.

UR - http://www.scopus.com/inward/record.url?scp=84879636676&partnerID=8YFLogxK

U2 - 10.1134/S003602361303011X

DO - 10.1134/S003602361303011X

M3 - Article

AN - SCOPUS:84879636676

VL - 58

SP - 320

EP - 330

JO - Russian Journal of Inorganic Chemistry

JF - Russian Journal of Inorganic Chemistry

SN - 0036-0236

IS - 3

ER -