ic960683c_si_001.pdf (1.21 MB)
Heteroleptic Lanthanide Complexes with Aryloxide Ligands. Synthesis and Structural Characterization of Divalent and Trivalent Samarium Aryloxide/Halide and Aryloxide/Cyclopentadienide Complexes
journal contribution
posted on 1996-12-04, 00:00 authored by Zhaomin Hou, Akira Fujita, Takashi Yoshimura, Aldo Jesorka, Yugen Zhang, Hiroshi Yamazaki, Yasuo WakatsukiSynthesis of a new class of heteroleptic samarium
aryloxide complexes has been achieved by the use of
homoleptic
samarium(II) bis(aryloxide)
Sm(OAr)2(THF)3 (1, Ar =
C6H2But2-2,6-Me-4)
as a starting material, which is easily
obtained by reaction of
Sm(N(SiMe3)2)2(THF)2
with 2 equiv of ArOH in THF. 1 reacts with 1 equiv of
SmI2 in
THF to give Sm(II) mixed aryloxide/iodide
[(ArO)Sm(μ-I)(THF)3]2
(2), which adopts a dimeric structure
via
very weak Sm···I (3.534(2) Å) interactions. Reaction
of 2 with C5Me5K in THF/HMPA
affords the corresponding
Sm(II) aryloxide/cyclopentadienide
(C5Me5)Sm(OAr)(HMPA)2
(3). Oxidation of 1 with 0.5 equiv of
I2 in THF
gives monomeric samarium(III) aryloxide/iodide
(ArO)2SmI(THF)2 (4), while
the similar reaction of 1 with
ClCH2CH2Cl or tBuCl in THF affords dimeric
samarium(III) aryloxide/chloride
[(ArO)2Sm(μ-Cl)(THF)]2
(5). Crystal
data for 1: monoclinic, space group
P21, a = 9.903(3) Å,
b = 16.718(5) Å, c = 13.267(2) Å,
β = 95.17(2)°, V
= 2187(2) Å3, Z = 2,
Dc = 1.223 g cm-3,
R = 0.0634. Crystal data for 2·2THF:
monoclinic, space group
P21/a,
a = 18.330(6) Å, b = 14.320(4) Å,
c = 13.949(3) Å, β = 103.16(2)°,
V = 3563(2) Å3, Z = 2,
Dc = 1.46 g
cm-3,
R = 0.0606. Crystal data for 3:
triclinic, space group P1̄, a =
10.528(1) Å, b = 12.335(2) Å, c =
19.260(2) Å,
α = 101.33(1)°, β = 95.230(9)°, γ =
108.54(1)°, V = 2293.1(5) Å3,
Z = 2, Dc = 1.25 g
cm-3, R = 0.0358.
Crystal data for 4: monoclinic, space group
C2/c, a = 17.191(7) Å,
b = 10.737(6) Å, c = 21.773(7) Å,
β =
98.80(3)°, V = 3971(3) Å3,
Z = 4, Dc = 1.44 g
cm-3, R = 0.0467. Crystal
data for 5: monoclinic, space group
P21/n, a =
13.750(3) Å, b = 17.231(3) Å, c =
14.973(6) Å, β = 95.81(2)°, V =
3529(2) Å3, Z = 2,
Dc = 1.31
g cm-3, R = 0.0557.