TY - JOUR
T1 - Complexation equilibria and structures of dimethyltin(IV) complexes with N-methyliminodiacetate, pyridine-2,6-dicarboxylate, ethylenediamine-N,N′-diacetate and ethylenediamine-N,N,N′,N′-tetraacetate
AU - Aizawa, Sen Ichi
AU - Natsume, Takayuki
AU - Hatano, Keiichiro
AU - Funahashi, Shigenobu
N1 - Funding Information:
This work was partly supported by Grants-in-Aid for Scientific Research (Nos. 06640779, 07454199 and 07504003) from the Ministry of Education, Science and Culture of Japan. S.A. gratefully acknowledges financial support by a grant from the Kurata Foundation.
PY - 1996/7/15
Y1 - 1996/7/15
N2 - The complexation equilibria of the dimethyltin(IV) ion with N-methyliminodiacetate (mida), pyridine-2,6-dicarboxylate (pdc), ethylenediamine-N,N′-diacetate (edda) and ethylenediamine-N,N,N′,N′-tetraacetate (edta) have been investigated in aqueous solution at 25.0 °C and I = 0.1 mol dm-3 ((H, Na)NO3) by potentiometric measurements. The overall stability constants βpqr for [(SnMe2)pHqLr](2p+q-nr)+ (n = 2 for L = mida, pdc, edda; n = 4 for L = edta) defined as [[(SnMe2)pHqLr] (2p+q-nr)+] [SnMe22+]-p[H+]-q[L n-]-r are evaluated as follows: log β1-11 = 2.53(3), log β101 = 9.625(4) and log β112 = 20.73(4) for L = mida; log β101 = 10.533(6), log β111 = 12.65(5) and log β112 = 17.69(3) for L = pdc; log β101 = 12.412(8), log β111 = 15.75(3), log β112 = 24.12(4) and log β122 = 30.87(4) for L = edda; log β2-21 = 4.75(1), log β2-11 = 10.44(2) and log β201 = 15.41(2) for L = edta. The crystal structures of [SnMe2(mida) (H2O)]·H2O, [SnMe2(pdc) (H2O)] · H2O, [SnMe2(edda)] and [(SnMe2)2(edta) (H2O)2] · H2O have been determined by X-ray crystal structure analyses. The mida and pdc complexes have a dimeric structure which consists of distorted pentagonal-bipyramidal tin units with two methyl groups in the axial position. The edda complex has a distorted octahedral monomer structure with two methyl groups in the cis position. The edta complex consists of a polymer structure with spanning edta ligands in which each tin unit has a geometry quite analogous to those of the mida and pdc complexes. The preference in geometry of the dimethyltin(IV) complexes is discussed in terms of the effects of the bound ligands. The dimethyltin(IV) complexes formed in aqueous solution have been characterized on the basis of the molecular structures in the crystals and the values of the stability constants and pKa.
AB - The complexation equilibria of the dimethyltin(IV) ion with N-methyliminodiacetate (mida), pyridine-2,6-dicarboxylate (pdc), ethylenediamine-N,N′-diacetate (edda) and ethylenediamine-N,N,N′,N′-tetraacetate (edta) have been investigated in aqueous solution at 25.0 °C and I = 0.1 mol dm-3 ((H, Na)NO3) by potentiometric measurements. The overall stability constants βpqr for [(SnMe2)pHqLr](2p+q-nr)+ (n = 2 for L = mida, pdc, edda; n = 4 for L = edta) defined as [[(SnMe2)pHqLr] (2p+q-nr)+] [SnMe22+]-p[H+]-q[L n-]-r are evaluated as follows: log β1-11 = 2.53(3), log β101 = 9.625(4) and log β112 = 20.73(4) for L = mida; log β101 = 10.533(6), log β111 = 12.65(5) and log β112 = 17.69(3) for L = pdc; log β101 = 12.412(8), log β111 = 15.75(3), log β112 = 24.12(4) and log β122 = 30.87(4) for L = edda; log β2-21 = 4.75(1), log β2-11 = 10.44(2) and log β201 = 15.41(2) for L = edta. The crystal structures of [SnMe2(mida) (H2O)]·H2O, [SnMe2(pdc) (H2O)] · H2O, [SnMe2(edda)] and [(SnMe2)2(edta) (H2O)2] · H2O have been determined by X-ray crystal structure analyses. The mida and pdc complexes have a dimeric structure which consists of distorted pentagonal-bipyramidal tin units with two methyl groups in the axial position. The edda complex has a distorted octahedral monomer structure with two methyl groups in the cis position. The edta complex consists of a polymer structure with spanning edta ligands in which each tin unit has a geometry quite analogous to those of the mida and pdc complexes. The preference in geometry of the dimethyltin(IV) complexes is discussed in terms of the effects of the bound ligands. The dimethyltin(IV) complexes formed in aqueous solution have been characterized on the basis of the molecular structures in the crystals and the values of the stability constants and pKa.
KW - Alkyl complexes
KW - Aminopolycarboxylate complexes
KW - Complexation equilibrium
KW - Crystal structures
KW - Tin complexes
UR - http://www.scopus.com/inward/record.url?scp=0000088534&partnerID=8YFLogxK
U2 - 10.1016/0020-1693(95)05011-6
DO - 10.1016/0020-1693(95)05011-6
M3 - 学術論文
AN - SCOPUS:0000088534
SN - 0020-1693
VL - 248
SP - 215
EP - 224
JO - Inorganica Chimica Acta
JF - Inorganica Chimica Acta
IS - 2
ER -