KINETIC AND THERMODYNAMIC PRODUCTS IN THE REACTION OF [RUCL2(CO)2]N WITH PYRIDINECARBALDIMINE LIGANDS AND THE CRYSTAL-STRUCTURE OF PYRID-2-YLMETHOXYMETHYL)(3-ISOPROPOXYPROPYL)AMINE)
B. Deklerkengels et al., KINETIC AND THERMODYNAMIC PRODUCTS IN THE REACTION OF [RUCL2(CO)2]N WITH PYRIDINECARBALDIMINE LIGANDS AND THE CRYSTAL-STRUCTURE OF PYRID-2-YLMETHOXYMETHYL)(3-ISOPROPOXYPROPYL)AMINE), Inorganic chemistry, 32(24), 1993, pp. 5528-5535
The reaction of pyridinecarbaldehyde with the appropriate amines H2NR
(R = CH2CH2OCH3, CH2CH2CH2OCH(CH3)2) yielded the new pyridinecarbaldim
ine ligands CH3OCH2CH2-Pyca (b) and iPrOCH2CH2CH2-Pyca (c), respective
ly. The reaction of n equiv of R-Pyca ligand (iPr-Pyca = a) with the p
olymer [RuCl2(CO)2]n led to the formation of monomeric ruthenium(II) c
omplexes of composition Ru(CO)2Cl2(R-Pyca). The stereochemistry of the
se complexes could be controlled by altering the reaction conditions;
i.e., in dichloromethane at ambient temperature the kinetic product tr
ans-Cl2Ru(CO)2(R-Pyca) (1) is formed in 75-95% yield. Heating the kine
tic product for 80 h in xylene or starting the reaction of the ligand
with [RuCl2(CO)2]n in toluene at reflux temperature gave the thermodyn
amic cis-product (2) in high yields (90-95%). In the reaction of [RuI2
(CO)2]n with the corresponding ligands only one isomer was formed: tra
ns-12Ru(CO)2(R-Pyca) (3). If the reaction of c with the polymer was ca
rried out in methanol at room temperature, pyrid-2-ylmethoxymethyl)(3-
isopropoxypropyl)amine) (4c) was obtained, in which a methanol molecul
e has added to the imine function of the ligand. The X-ray structure d
etermination of the yellow crystals of 4c(Cl5H22N2O4CI2Ru) was carried
out. Crystal data for 4c: monoclinic, space group P2(1)/c (No. 14) wi
th a = 8.213(1) angstrom, b = 12.952(4) angstrom, c = 18.009(4) angstr
om, beta =95.80(1)-degrees, V = 1905.8(8) angstrom3, and Z = 4. A spec
ial feature of the complex is the intramolecular N-H...O bridge, forme
d between the amine hydrogen and the ether oxygen of the ligand. The m
ethanolysis is acid catalyzed. The reaction of a or b with [RuCl2(CO)2
]n in methanol led to new, unidentified products, whose NMR and IR dat
a showed that no methanolysis had taken place.