Manipulation of reaction pathways in redox transmetallation-ligand exchange syntheses of lanthanoid(ii)/(iii) aryloxide complexes

Article abstract of DOI:10.1039/b511609k

Redox transmetallation/ligand exchange reactions of lanthanoid metals (Ln), Hg(C₆F₅)₂ and HOAr^OMe (Ar ^OMe = C₆H₂-2,6-Bu^t-4-OMe), in thf (tetrahydrofuran) gave, for Ln = Yb, Yb(OAr^OMe)₂(thf) ₃, and for Ln = Sm, a mixture of Sm^II(OAr ^OMe)₂(thf)₃ and mainly Sm^III(Ar ^OMe)₃(thf)·thf. X-Ray structure determinations show the divalent complexes to have distorted square-pyramidal stereochemistry with transoid thf and OAr^OMe ligands in the basal plane. Treatment of Yb(OAr^OMe)₂(thf)₃ with diethyl ether or PhMe at room temperature gave Yb(OAr^OMe)₂ or Yb(OAr ^OMe)₂·0.5PhMe. For lanthanoids Ln = Nd, Er or Y, the reactions with Hg(C₆F₅)₂ and HOAr ^OMe yielded complex product mixtures, from one of which the novel erbium aryloxide fluoride cage Er₃(OAr^OMe) ₄(μ₂-F)₃(μ₃-F) ₂(thf)₄·thf·0.5C₆H₁₄ was isolated. The cage core consists of a triangle of Er atoms joined to two μ₃-fluoride ligands and three further μ₂-fluorides bridge adjacent Er atoms. One of the Er atoms is six-coordinate with additionally two OAr^OMe ligands whilst the other two have one OAr^OMe and two thf ligands and are seven coordinate. Substitution of Hg(C₆F₅)₂ by Hg(CCPh)₂ in the redox transmetallation/ligand exchange reactions gave the new derivatives Ln(OAr ^OMe)₃(thf)·thf (Ln = La, Pr, Nd, Sm, Gd, Ho) in good yields whilst Ln = Yb gave Yb(OAr^OMe)₂(thf) ₃. Recrystallisation of Sm(OAr^OMe)₃(thf) ·thf from dme (1,2-dimethoxyethane) yielded Sm(OAr^OMe) ₃(dme). Structural characterisation of Ln(OAr^OMe) ₃(thf)·thf (Ln = Nd, Ho) and Sm(OAr^OMe) ₃(dme) showed monomeric four-coordinate distorted tetrahedral and five-coordinate distorted square-pyramidal complexes respectively. For the smaller lanthanoids Ln = Y, Er or Lu, reactions with Hg(CCPh)₂ and HOAr^OMe gave the mixed aryloxide/alkynide complexes Ln(OAr ^OMe)₂(CCPh)(thf)₂. Oxidation of the divalent ytterbium aryloxide Yb(OAr^OMe)₂(thf)₃ by Hg(CCPh)₂ in thf gave the analogous Yb(OAr^OMe) ₂(CCPh)(thf)₂. The erbium alkynide Er(OAr ^OMe)₂(CCPh)(thf)₂·0.25C ₆H₁₄ has distorted square-pyramidal stereochemistry with transoid OAr^OMe and thf ligands in the basal plane and a rare (for Ln) terminal alkynide ligand in the apical position. The reactive Lu-C bond in the Lu(OAr^OMe)₂(CCPh)(thf)₂ complexes could be slowly cleaved by free HOAr^OMe in hydrocarbon solvents, yielding Lu(OAr^OMe)₃ species and fortuitous partial hydrolysis of Er(Ar^OMe)₂(CCPh)(thf)₂ gave the dimeric Er(OAr^OMe)₂(μ-OH)₂₂. The Royal Society of Chemistry 2006.

Full text of DOI:10.1039/b511609k

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Manipulation of reaction pathways in redox transmetallation–ligand
exchange syntheses of lanthanoid(II)/(III) aryloxide complexes†
Glen B. Deacon,*a Gary D. Fallon,a Craig M. Forsyth,a Stuart C. Harris,a Peter C. Junk,a Brian W. Skeltonb
and Allan H. Whiteb
Received 15th August 2005, Accepted 5th October 2005
First published as an Advance Article on the web 28th October 2005
DOI: 10.1039/b511609k
Redox transmetallation/ligand exchange reactions of lanthanoid metals (Ln), Hg(C6F5)2 and HOArOMe
(ArOMe = C6H2-2,6-But-4-OMe), in thf (tetrahydrofuran) gave, for Ln = Yb, [Yb(OArOMe)2(thf)3], and
for Ln = Sm, a mixture of [SmII(OArOMe)2(thf)3] and mainly [SmIII(ArOMe)3(thf)]·thf. X-Ray structure
determinations show the divalent complexes to have distorted square-pyramidal stereochemistry with
transoid thf and OArOMe ligands in the basal plane. Treatment of [Yb(OArOMe)2(thf)3] with diethyl ether
or PhMe at room temperature gave [Yb(OArOMe)2] or [Yb(OArOMe)2]·0.5PhMe. For lanthanoids Ln =
Nd, Er or Y, the reactions with Hg(C6F5)2 and HOArOMe yielded complex product mixtures, from one of
which the novel erbium aryloxide fluoride cage [Er3(OArOMe)4(l2-F)3(l3-F)2(thf)4]·thf·0.5C6H14 was
isolated. The cage core consists of a triangle of Er atoms joined to two l3-fluoride ligands and three
further l2-fluorides bridge adjacent Er atoms. One of the Er atoms is six-coordinate with additionally
two OArOMe ligands whilst the other two have one OArOMe and two thf ligands and are seven coordinate.
Substitution of Hg(C6F5)2 by Hg(CCPh)2 in the redox transmetallation/ligand exchange reactions gave
the new derivatives [Ln(OArOMe)3(thf)]·thf (Ln = La, Pr, Nd, Sm, Gd, Ho) in good yields whilst Ln =
Yb gave [Yb(OArOMe)2(thf)3]. Recrystallisation of [Sm(OArOMe)3(thf)]·thf from dme
(1,2-dimethoxyethane) yielded [Sm(OArOMe)3(dme)]. Structural characterisation of
[Ln(OArOMe)3(thf)]·thf (Ln = Nd, Ho) and [Sm(OArOMe)3(dme)] showed monomeric four-coordinate
distorted tetrahedral and five-coordinate distorted square-pyramidal complexes respectively. For the
smaller lanthanoids Ln = Y, Er or Lu, reactions with Hg(CCPh)2 and HOArOMe gave the mixed
aryloxide/alkynide complexes [Ln(OArOMe)2(CCPh)(thf)2]. Oxidation of the divalent ytterbium
aryloxide [Yb(OArOMe)2(thf)3] by Hg(CCPh)2 in thf gave the analogous [Yb(OArOMe)2(CCPh)(thf)2]. The
erbium alkynide [Er(OArOMe)2(CCPh)(thf)2]·0.25C6H14 has distorted square-pyramidal stereochemistry
with transoid OArOMe and thf ligands in the basal plane and a rare (for Ln) terminal alkynide ligand in
the apical position. The reactive Lu–C bond in the [Lu(OArOMe)2(CCPh)(thf)2] complexes could be
slowly cleaved by free HOArOMe in hydrocarbon solvents, yielding Lu(OArOMe)3 species and fortuitous
partial hydrolysis of [Er(ArOMe)2(CCPh)(thf)2] gave the dimeric [Er(OArOMe)2(l-OH)2]2.
Such ligands are also attractive alternatives to cyclopentadienyls
Introduction
as supports for homogeneous lanthanoid catalysts,2f ,4 for soluble
one-electron reducing agents (including N2 reduction5c),5 and for
use in MOCVD and sol–gel precursors.1
Contrasting the predominant use of metathesis reactions for
the synthesis of lanthanoid metal–organic complexes,1 redox
transmetallation/ligand exchange reactions (eqn (1) and (2)) are
a competitive route to these species.6
The preparation of low coordination number (≤6) lanthanoid
complexes has been, and remains, significant synthetic
a
challenge.1,2 Aryloxide ligands that incorporate bulky substituents
proximal to the ligating oxygen atom have made a major
contribution in achieving these targets. For example, 2,6-di-tert-
butylphenolates have yielded key representatives of three- to
five-coordinate lanthanoid complexes, both in the trivalent and
divalent oxidation states (e.g. [Ln(OAr)3], [Ln(OAr)(l-OAr)]2,
(1)
Ln + HgR2 + 2 LH → LnL2 + Hg + 2 RH
[Ln(OAr)3(thf)], [Ln(OAr)2(thf)2], [Ln(OAr)2(thf)3]; OAr
=
(2)
2 Ln + 3 HgR2 + 6 LH → 2 LnL3 + 3 Hg + 6 RH
OC6H2-2,6-But2-4-R, R = H, Me, But, thf = tetrahydrofuran).3
Not only do the bulky But groups inhibit the coordination of neu-
tral donors but they also enhance the solubility in hydrocarbons.
These syntheses employ simply prepared, air-stable diorganomer-
cury(II) reagents, for example Hg(C6F5)2, and are presumed to
involve the initial formation of Ln–R species. This has been
demonstrated for divalent derivatives, since [Ln(C6F5)2(thf)n]
(Ln = Yb, n = 4; Ln = Eu, n = 5) can be isolated from
aSchool of Chemistry, Monash University, Clayton, 3800, Australia. E-mail:
glen.deacon@sci.monash.edu.au; Fax: +613 9905 4597; Tel: +613 9905
4568
7
reactions of Ln with Hg(C6F5)2 and give Ln(OAr)2 complexes
with phenols.3f On the other hand, reaction (2) is successful even
though the corresponding Ln(C6F5)3 complexes are unobtainable
from Ln metal and Hg(C6F5)2. A major isolable product is LnF3,8
bDepartment of Chemistry, University of Western Australia, Crawley, 6009,
Australia
† Dedicated to the memory of Professor Ian Rothwell, 1955–2004.
802 | Dalton Trans., 2006, 802–812
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presumably derived from decomposition of LnIII–C6F5 species (cf .
stable LnPh3(thf)3 from Ln and HgPh2).9
◦
˚
Table 1 Bond distances (A) and angles ( ) in [Ln(OAr)2(thf)3]·thf (Ln =
Sm, Yb)
The potential of redox transmetallation/ligand exchange as a
route to 2,6-di-tert-butyl phenolates has not been fully realised,
as it has not been examined for the wide range of possible
trivalent complexes Ln(OAr)3. Moreover, whilst the reactions
(1) and (2) are seemingly straightforward for the synthesis of
complexes of the type [Ln(L)3(S)n] (S = solvent), there is potential,
especially through steric control, to induce formation of mixed-
ligand derivatives (see e.g. use of bulky formamidinates10). This
capability has now been realised for 2,6-di-tert-butyl phenolates
and we now report a detailed study of reactions of lanthanoid
metals, mercurials HgR2 (R = C6F5, CCPh) and the phenol
HOArOMe (ArOMe = C6H2-2,6-But-4-OMe). Not only do these give
classical Ln(OAr)2 or Ln(OAr)3 complexes but also a novel lan-
thanoid aryloxide/fluoride cage and rare examples of lanthanoid
aryloxide/alkynide derivatives. This specific phenolate has not
previously been examined as a ligand for lanthanoids, and has
the possibility of eliminating donor-solvent–Ln coordination by
forming intermolecular Ln–OMe bonds.
Sm
Yb
Ln–O(OAr)
Ln–O(thf)
2.299(7)
2.305(7)
2.548(8)
2.580(8)
2.584(8)
2.229(5)
2.232(5)
2.418(6)
2.449(6)
2.462(6)
O(OAr)–Ln–O(OAr)
O(OAr)–Ln–O(thf)ax
146.4(2)
108.1(2)
105.5(3)
88.9(2)
90.1(2)
89.4(3)
90.5(2)
178.0(3)
90.2(3)
91.8(3)
147.0(2)
106.7(2)
106.3(2)
88.7(2)
90.3(2)
88.3(2)
89.8(2)
174.9(2)
90.6(2)
94.5(2)
O(OAr)–Ln–O(thf)eq
O(thf)–Ln–O(thf)
as indicated by the near linear O(thf)–Ln–O(thf) angle (Table 1).
The samarium derivative (Fig. 1) generally has longer Ln–O
distances (Table 1) consistent with the larger ionic radius of
Sm2+ than Yb2+.13 However, for Ln–OAr the difference is less
Results and discussion
˚
than expected (approximately 0.14 A) suggesting greater steric
Reaction of Hg(C6F5)2, HOArOMe and an excess of ytterbium in
thf gave, after crystallisation from thf, the yellow ytterbium(II)
complex [Yb(OArOMe)2(thf)3] (eqn (1), R = C6F5, L = OArOMe) in
good yield. This parallels established syntheses of ytterbium(II)
aryloxides with closely related ligands (e.g. OC6H2-2,6-But-4-R,
R = H, Me, But),3f and contrasts OC6H3-2,6-Ph2 (Odpp) which
gave only a Yb(Odpp)3 complex.6 The analogous reaction of
Hg(C6F5)2, HOArOMe and samarium, which also has an accessible
LnII state, gave only a very low yield of [SmII(OArOMe)2(thf)3] with
the major product, [Sm(OArOMe)3(thf)]·thf, in the LnIII oxidation
state. The contrasting outcomes for ytterbium and samarium can
be related to the greater reducing ability11 of SmII which facili-
tates oxidation of the divalent species by unreacted Hg(C6F5)2.
Subsequent protolysis by HOArOMe of a Sm(OArOMe)2(C6F5)
intermediate would give the observed SmIII product. Evidence for
formation of Sm(OArOMe)2(C6F5) was obtained from oxidation of
Sm(OArOMe)2 by Hg(C6F5)2 (eqn (3)) on an NMR tube scale in
C6D6–thf.
crowding in the ytterbium complex. The structures are comparable
with those of closely related derivatives [Yb(OArMe)2(thf)3]3d and
[Sm(OArMe)2(thf)3]14 (ArMe = C6H2-2,6-But2-4-Me) and show that
the methoxy substitution in the current aryloxide ligand has little
structural influence in the presence of thf co-ligands. However,
[Yb(OArOMe)2(thf)3] differs completely from [Yb(OArMe)2(thf)3] on
treatment with diethyl ether or toluene. The present complex is
converted by both into a homoleptic species [Yb(OArOMe)2] as a
pyrophoric red powder, either containing a trace of ether from
the former treatment or as a toluene solvate from the latter. Cor-
responding reactions of the 4-Me substituted [Yb(OArMe)2(thf)3]
yield either [Yb(OArMe)2(OEt2)2] or [Yb(OArMe)2(thf)2],3d,f ,h both
highly soluble. It is possible that dissociative loss of thf enables
the methoxy groups of [Yb(OArOMe)2] to compete in coordination
to ytterbium, forming a MeO–Yb linked polymer, as suggested by
the low solubility. Single crystals could not be obtained.
The reactions of Hg(C6F5)2 and HOArOMe with the lanthanoid
metals Nd, Er, Y were also attempted, targeting [Ln(OArOMe)3]
2 Sm(OArOMe)2 + Hg(C6F5)2 → 2 Sm(OArOMe)2(C6F5) + Hg (3)
The brown divalent complex rapidly changed to a yellow SmIII
colour and Hg metal deposited. Broad 19F NMR resonances
at −124.6, −158.3 and −164.8 ppm were consistent with the
formation of a SmIII–C6F5 species. By comparison, values for
[SmCp*2(C6F5)]2 (Cp* = C5Me5) are reported at −146.8, o-F;
−152.0, p-F; −161.4, m-F; ppm, but the position of the o-F
resonance is perturbed by a Sm–F interaction.12 The much greater
yield of [Sm(OArOMe)3(thf)]·thf than [Sm(OArOMe)2(thf)3] contrasts
the high yield of [Sm(pin)2(thf)4] from an analogous reaction of
Sm, Hg(C6F5)2 and 2-phenylindole (pinH).6
The compositions of the divalent complexes were supported by
elemental and spectroscopic analyses and their structures were
determined by single-crystal X-ray studies of thf solvates. Both
complexes are monomeric (one molecule in the asymmetric unit)
and five coordinate with transoid aryloxide ligands and square-
based pyramidal geometry, distorted toward trigonal bipyramidal
Fig. 1 Molecular structure of [Sm(OArOMe)2(thf)3]·thf showing 30%
thermal ellipsoids. Lattice solvent and hydrogen atoms have been omitted
for clarity.
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complexes. (These elements generally do not exhibit the +2
oxidation states in solution although recent exciting new diva-
lent complexes of La, Nd, Dy and Tm15 clearly demonstrate
that these states can exist.) However, crystalline products of a
complex nature and with metal contents higher than expected
for simple [Ln(OArOMe)3(thf)] species were obtained. Their IR
spectra indicated the presence of OArOMe and thf. No m(OH)
absorptions were detected eliminating accidental hydrolysis. The
NMR spectra of the Nd and Y products exhibited multi-
ple aryloxide environments, and for Nd, one set of signals
matched those of authentic [Nd(OArOMe)3(thf)]·thf (see below).
Subsequently, a single-crystal X-ray study of the pink Er prod-
uct showed this to be an aryloxo-fluoro-erbium(III) complex
[Er3(OArOMe)4(l2-F)3(l3-F)2(thf)4]·thf·0.5C6H14. Repeat reactions
gave the same product in similar low yields. The presence
of fluoride presumably results from formation of Er–F bonds
during decomposition of an unstable Er–C6F5 species (Scheme 1)
through processes similar to those proposed for other M–C6F5
species.7a,8,12,16,17 This proposal was supported by the detection
of polyfluorobiphenyls in the evaporated reaction residue. The
synthetic results for the larger Nd, and the smaller Er and Y
elements contrast the good yield of [Sm(OArOMe)3(thf)3]·thf from
Sm/Hg(C6F5)2/HOArOMe (above) suggesting moderate stability
of the intermediate Sm(OArOMe)2(C6F5) complex. Re-examination
of the 19F NMR spectrum of the Sm(OArOMe)2(C6F5) solution
from reaction (3) after 11 days showed a decrease in the
intensity of the original peaks (∼50%) and the appearance
of several new fluorine containing species, including tetrafluo-
robenzobicyclo[2.2.2]octatriene, the Diels–Alder coupling prod-
uct of tetrafluorobenzyne and C6D6 (as also observed in the
decomposition of [CeCpꢀ2(C6F5)]).17 Thus, although susceptible to
fluoride elimination, the Sm(OArOMe)2(C6F5) intermediate appears
sufficiently stable to be cleaved by HOArOMe. Consistent with this,
[SmCp*2(C6F5)]2 is reported to be stable for up to a week at room
temperature,12 whereas [CeCpꢀ2(C6F5)] (Cpꢀ = C5H2-1,3,5-But3)
is thermally unstable, decomposing into tetrafluorobenzyne and
CeCpꢀ2F.17
The molecular structure of [Er3(OArOMe)4(l2-F)3(l3-
F)2(thf)4]·thf·0.5C6H14 is shown in Fig. 2, with selected bond
distances and angles listed in Table 2. The complex has a triangular
array of erbium atoms with each edge bridged by a l2-fluoride
and both faces of the Er3 triangle capped by a l3-fluoride.
Scheme 1 Proposed pathway for the formation of Ln(OAr)xFy species in
the Ln/Hg(C6F5)2/HOAr reactions.
Fig. 2 Structure of [Er3(OArOMe)4(l2-F)3(l3-F)2(thf)4]·thf·0.5C6H14.
◦
Table 2 Bond distances (A) and angles ( ) in [Er3(OArOMe)4(l2-F)3(l3-F)2(thf)4]·thf·0.5C6H14
˚
Er(1)
Er(2)
Er(3)
Er(1)
Er(2)
Er(3)
Er–O(OAr)
2.083(8)
2.086(8)
2.185(7)
2.194(6)
2.085(8)
2.094(8)
Er–l3-F
2.386(6)
2.406(6)
2.294(6)
2.415(7)
2.380(9)
2.420(9)
2.280(6)
2.449(7)
2.355(8)
2.456(9)
Er–l2-F
2.204(7)
2.209(7)
2.188(7)
2.207(6)
Er–O(thf)
O(OAr)–Er–O(OAr)
l3 − F–Er–l3 − F
l3 − F–Er–l2 − F
105.3(3)
61.7(2)
69.5(2)
69.8(2)
70.1(2)
70.8(2)
133.2(2)
99.8(3)
154.9(3)
93.2(3)
161.5(3)
103.3(3)
104.1(3)
102.7(3)
105.6(3)
O(thf)–Ln–l3-F
O(thf)–Ln–l2-F
78.0(3)
124.8(3)
138.0(3)
138.8(3)
74.7(3)
110.7(3)
81.7(3)
149.0(3)
82.3(3)
116.2(3)
76.1(3)
76.7(2)
128.9(2)
137.8(3)
136.2(3)
75.8(3)
111.1(3)
81.6(3)
149.2(3)
83.3(3)
104.5(3)
78.1(3)
62.9(2)
69.7(2)
70.4(2)
71.3(2)
71.3(2)
134.3(2)
95.0(3)
152.6(3)
62.5(2)
68.6(2)
68.6(2)
71.6(2)
72.6(2)
133.2(3)
97.1(3)
151.5(3)
l2 − F–Er–l2 − F
O(OAr)–Er–l3-F
O(OAr)–Er–O(thf)
O(thf)–Er–O(thf)
O(OAr)–Er–l2-F
88.6(3)
120.0(3)
87.0(3)
126.4(3)
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In addition, six-coordinate Er(1) has two terminal aryloxides,
whilst Er(2) and Er(3) are seven-coordinate each with one
aryloxide and two thf ligands. The M3(l2-X)3(l3-X)2 core of
the current structure has been observed in trimetallic chlo-
ride bridged complexes, e.g. [{Gd(Cp*)(thf)}2(l2-Cl)3(l3-Cl)2-
Na(thf)]2,18a [{Er(C5H4C5H9)(thf)}2(l2-Cl)3(l3-Cl)2Na(thf)]2,18b
[Nd(C5H4But)(thf)}2(l2-Cl)3(l3-Cl)2Na(thf)]n,18c and in the
recently described cation [{YbCp(thf)}3(l2-Cl)3(l3-Cl)2]+.18d There
are related Ln3F5 or LnM2F5 substructure units in [Yb5(Cp*)6-
(l2-F)6(l3-F)2(l4-F)],19a and in the Ln-Ti-fluoride [La{(Ti(C5-
Me4Et)F)2(l2-F)3(l3-F)2}3].19b,c An aryloxide cage with similar
[Ln(OArOMe)3(thf)]·thf, Ln = Nd, Ho and [Sm(OArOMe)3(dme)],
one molecule comprising the asymmetric unit in each case.
The molecular structure of monomeric [Ho(OArOMe)3(thf)]·thf
is depicted in Fig. 3. [Nd(OArOMe)3(thf)]·thf is isomorphous
with the Ho complex and both are four-coordinate with a
highly distorted geometry as indicated by large variations of
the interligand angles from regular tetrahedral (Table 3). The
Ln–O bond distances are consistent with those for the known,
and structurally similar, [Ln(OArMe)3(thf)] (Ln = Nd, Sm)23 and
[Yb(OArBu)3(thf)]3e (ArBu = C6H2-2,4,6-But3) after accounting for
differences in ionic radii.13 Five-coordinate [Sm(OArOMe)3(dme)]
(Fig. 4) has an approximately square-pyramidal geometry with an
OArOMe ligand (O(31)) in the apical position. The basal plane is
highly distorted as shown by the narrow bite of the chelating dme
ligand (Table 3) and the large inter aryloxide angle O(11)–Sm–
O(21) 126.0(2)◦. Interestingly, the arrangement of the three OAr
ligands in [Sm(OArOMe)3(dme)] is very similar to that observed in
[Ln(OArOMe)3(thf)]·thf complexes as shown by the O(OAr)–Ln–
O(OAr) angles and the variation in Ln–OAr distances is in line
connectivity is [Nd3(thf)4(OAr)4(l2-OAr)3(l3-OAr)2] (Ar
=
C6H3-3,5-But2),20 whereas dimeric aryloxo-ytterbium(III) fluorides
[Yb(OAr)2(l2-F)(thf)]2 (Ar = C6H2-2,6-But2-4-R, R = H, Me, But)
have been isolated from oxidation reactions of Yb(OAr)2(thf)n by
fluorocarbon substrates.5b
The six-membered Er3(l2-F)3 ring in [Er3(OArOMe)4(l2-F)3(l3-
˚
F)2(thf)4]·thf·0.5C6H14 is almost planar (average deviation 0.06 A)
with symmetrical l2-F bridging. The range of Er–l2-F distances
˚
˚
(2.185(7)-2.209(7) A) is less than the 0.055 A difference in the
ionic radii of six- and seven-coordinate Er3+.13 The l3-fluorides,
F(1) and F(2), lie above and below the six-membered ring with
longer Er–F bonds than for Er–l2-F. Further, the Er3(l3-F)2
bonding at seven coordinate Er(2) and Er(3) is asymmetric with
the longest Er–F distances associated with a transoid disposition
to negatively charged oxygen atoms (e.g. Er(2)–F(1) 2.415(7)
◦
˚
˚
A; F(1)–Er(2)–O(5) 152.6(3) , cf. Er(2)–F(2) 2.294(6) A; F(2)–
◦
˚
Er(2)–O◦(5) 95.0(3) and Er(3)–F(2) 2.449(7) A; F(2)–Er(3)–O(7)
◦
˚
151.5(3) , cf. Er(2)–F(1) 2.280(6) A; F(1)–Er(3)–O(7) 97.1(3) ).
trans-Influences in lanthanoid complexes, including by aryloxide
ligands, are well established.21 At Er(1), both Er–l3-F are long as
both are transoid to an OArOMe ligand (Table 2). The aryloxide
ligands are strongly bound as indicated by the relatively short
Er–O(OArOMe) distances which are comparable with those of five-
coordinate [Er(OArMe)2Cl(thf)2]·PhMe 2.097(5) A, despite the
14c
˚
higher coordination numbers in the current structure.
The unsatisfactory performance of Hg(C6F5)2 in the preparation
of lanthanoid(III) complexes, Ln(OArOMe)3, by reaction (2) is
attributable to steric inhibition of protolysis of intermediate
Ln(OArOMe)2C6F5 species by the bulky HOArOMe. Accordingly de-
composition of the intermediate (Scheme 1) precedes substitution
of C6F5 by OArOMe. This contrasts the successful use of Hg(C6F5)2
in the syntheses of Ln(Odpp)3 complexes from the less bulky
2,6-diphenylphenol.6,21c Consequently, to avoid the formation
of lanthanoid-fluoride species, the use of Hg(CCPh)2 in these
reactions was investigated. The choice was based on comparable
reactivity to Hg(C6F5)2 with ytterbium.22 Thus, reaction of a
range of lanthanoids with Hg(CCPh)2 and HOArOMe gave pure
[Ln(OArOMe)3(thf)]·thf (Ln = La, Pr, Sm, Gd and Ho) complexes
in good yield (reaction (2), R = CCPh, L = OArOMe). For Ln =
Yb, the reaction with excess metal gave the divalent derivative
[Yb(OArOMe)2(thf)3] (reaction (1), R = CCPh, L = OArOMe) but for
Ln = Sm there was no evidence of formation of the corresponding
SmII complex, in contrast to the reaction using Hg(C6F5)2 as the
reagent (see above). Recrystallisation of [Sm(OArOMe)3(thf)]·thf
from dme (1,2-dimethoxyethane) afforded [Sm(OArOMe)3(dme)]
in which bidentate dme has replaced a monodentate thf. All
the isolated complexes gave satisfactory analytical and spectro-
scopic data and single-crystal X-ray structures were obtained for
Fig. 3 Molecular structure of [Ho(OArOMe)3(thf)]·thf.
◦
Table 3 Bond distances (A) and angles ( ) in [Ln(OArOMe)3(thf)]·thf (Ln =
˚
Nd, Ho) and [Sm(OArOMe)3(dme)]
Nd
Ho
Sm
Ln–O(OAr)
2.113(6)
2.140(5)
2.173(5)
2.502(6)
2.044(7)
2.054(7)
2.105(7)
2.370(7)
2.135(7)
2.179(6)
2.201(6)
2.512(8)
2.599(9)
Ln–O(thf/dme)
O(OAr)–Ln–O(OAr)
O(OAr)–Ln–O(thf/dme)
105.2(2)
109.4(2)
123.5(2)
85.6(2)
111.8(2)
121.7(2)
106.8(3)
110.6(3)
122.2(3)
86.9(3)
109.7(3)
120.7(3)
100.8(3)
110.6(2)
126.1(2)
77.1(3)
81.9(3)
94.3(3)
116.2(3)
122.6(2)
139.0(3)
62.7(2)
O(dme)–Ln–O(dme)
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reactive four-coordinate Lu(OArOMe)2(CCPh)(thf) species. That
the initial [Ln(OArOMe)2(CCPh)(thf)2] complexes are reactive with
smaller substrates was evident by the isolation of [Er(OArOMe)2(l-
OH)2(thf)2] during an attempted crystallisation of the correspond-
ing alkynyl and is presumably formed by adventitious hydrolysis
(eqn (7)).
Lu(OAr)2(CCPh) + HOAr → Lu(OAr)2(OAr) + HCCPh (6)
Er(OAr)2(CCPh) + H2O → Er(OAr)2(OH) + HCCPh
(7)
The structure of [Er(OArOMe)2(CCPh)(thf)2]·0.25C6H14 is shown
in Fig. 5 and that of centrosymmetric [Er(OArOMe)2(l-OH)(thf)]2
is shown in Fig. 6 with selected bond distances and angles in
Table 4. It is illustrative to consider these structures together since
both are five-coordinate ErL2X species and both have distorted
square-pyramidal coordination geometry. The alkynyl complex is
monomeric with a terminal CCPh ligand (apical), two transoid
Fig. 4 Molecular structure of [Sm(OArOMe)3(dme)].
with the differences in ionic radii.13 Therefore it would appear that
the dme ligand simply replaces the thf ligand in the coordination
sphere of the starting complex. However, the coordinated dme
has one longer Sm–O(dme) distance (Table 3), as observed in
24
˚
[Nd(Odpp)3(dme)]·thf (Nd–O(dme) 2.502(6) and 2.546(5) A).
The greater asymmetry of dme binding in the Sm complex may
be a result of the higher steric demands of the 2,6-di-tert-butyl
substituted aryloxide. The sum of steric coordination numbers25
for the two ligand sets is 7.48 (Odpp) and 9.01 (OArOMe), the latter
one of the largest observed for lanthanoid aryloxides (cf. 9.64 for
[Nd(OArMe)4][Na(thf)6].23a
An intriguing aspect of the reactions of lanthanoid metals with
Hg(CCPh)2 and HOArOMe emerged with the smaller lanthanoid
elements Y, Er and Lu. These also gave clean reactions and single
products but spectroscopic data clearly indicated retention of one
CCPh ligand per metal centre. Thus weak m(C≡C) absorption
bands were observed in the range 2074–2082 cm−1 which are
1
typical values for terminally bound Ln–CCPh moieties26 and H
NMR spectra of diamagnetic Y and Lu derivatives indicated a
2 : 1 : 2 aryloxide–alkynyl–thf ratio. Subsequently the identity of
one member was confirmed by a single-crystal X-ray structure
determination (see below) of [Er(OArOMe)2(CCPh)(thf)2] formed
by reaction (4). Since reaction of excess Yb with Hg(CCPh)2 and
HOArOMe gave divalent [Yb(OArOMe)2(thf)3], the missing member
of the alkynyl series was prepared by oxidation with Hg(CCPh)2
(eqn (5)).
Fig. 5 Molecular structure of [Er(OArOMe)2(CCPh)(thf)2]·0.25C6H14
2 Ln + 3 Hg(CCPh)2 + 4 HOAr
→ 2 Ln(OAr)2(CCPh) + 4 HCCPh + 3 Hg
(4)
(5)
2 Yb(OAr)2 + Hg(CCPh)2 → 2 Yb(OAr)2(CCPh) + Hg
The isolation of these mixed-ligand complexes only for the
smaller lanthanoids, despite sufficient HOArOMe to effect com-
plete protolysis, clearly suggests steric inhibition of the cleavage
of the final Ln–CCPh group. No reaction of HOArOMe with
isolated [Lu(OArOMe)2(CCPh)(thf)2] could be induced in D8-thf,
however, in C6D6, slow protolysis was observed to give the as
yet unisolated Lu(OArOMe
room temperature) (eqn (6)). Presumably, in a non-coordinating
solvent, prior dissociation of thf may occur giving a more
) (50% conversion after 3 days at
3
Fig. 6 Molecular structure of [Er(OArOMe)2(l-OH)(thf)]2. A: Atom
generated by symmetry operator: −x, −y, −z.
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◦
Table 4 Selected bond distances (A) and angles ( ) in [Er(OArOMe)2-
˚
respect to fluoride elimination, the LnL2CCPh derivatives were
readily isolable. These are important synthetic targets, having a
potentially reactive Ln–C residue, which can now be prepared in a
simple one-pot procedure from readily available or easily prepared
reagents.
(CCPh)(thf)2]·0.25C6H14 and [Er(OArOMe)2(OH)(thf)]2
X =
CCPh
OH
Ln–O(OAr)
Ln–C/O(X)
Ln–O(thf)
2.102(9)
2.172(8)
2.31(1)
2.056(4)
2.108(4)
2.213(5)
2.259(5)
2.365(5)
Experimental
2.302(9)
2.382(10)
General information
O(OAr)–Ln–O(OAr)
O(OAr)–Ln–C/O(X)
144.1(3)
104.8(4)
111.1(5)
106.5(2)
All products were air-sensitive and required use of Schlenk
and vacuum line techniques and manipulation in an inert
atmosphere. Solvents were dried by distillation over sodium
benzophenone. Elemental analyses (C, H, N) were performed by
the Campbell Microanalytical Laboratory, University of Otago,
Dunedin, New Zealand. Metal analyses were by EDTA titrations
with Xylenol Orange indicator, following acid digestion and
buffering. All bulk samples were dried for 3 h under vacuum
leading to loss of lattice solvent for [Ln(OArOMe)2(thf)3]·thf and
[Er(OArOMe)2(CCPh)(thf)2]·0.25C6H14. IR spectra were obtained
as Nujol mulls with a Perkin Elmer 1600 FTIR instrument. 1H and
19F NMR spectra were recorded on a Bruker AM300 spectrometer.
Vis/near IR spectra were obtained for solutions in a 1 mm quartz
cell using a Carey 17 spectrophotometer. Mass spectra of solid
samples were obtained using a VG-TRIO instrument with an
electron impact ion source and a locally modified probe for air-
sensitive materials. Listed m/z values for metal containing species
refer to the highest intensity peak of a cluster with the appropriate
isotope pattern (including 13C contributions). Lanthanoid metal
powders were obtained from Rhone Poulenc and stored under
nitrogen. 2,6-Di-tert-butyl-4-methoxyphenol was used as received
from Aldrich. Hg(C6F5)222 and Hg(CCPh)228 were prepared by the
literature methods.
101.2(2), 107.6(2)
103.1(2), 152.3(2)
68.7(2)
89.0(2)
110.9(2)
80.2(2)
134.1(2)
O(OH)–Ln–O(OH)
O(OAr)–Ln–O(thf)
86.5(4), 87.5(4)
88.4(4), 89.4(4)
95.5(6)
97.7(6)
166.5(4)
C/O(X)–Ln–O(thf)
O(thf)–Ln–O(thf)
aryloxides (O–Er–O 144.1(3)◦) and two transoid thf ligands and
is similar to the structure of [Ln(OArOMe)2(thf)3]·thf (Ln = Sm
(Fig. 1) or Yb) with CCPh replacing the apical thf. In contrast,
the hydroxyl complex is dimeric with bridging OH ligands and
two aryloxides in a cisoid disposition (O–Er–O 106.7(3)◦) and
one coordinated thf ligand. An OArOMe group occupies the
apical position. Since both complexes were crystallised from
thf–hexanes, the differing structures presumably reflect the high
stability of Ln–(l-OH)–Ln moieties in lanthanoid chemistry. A
bis(aryloxo)erbium chloride analogue of the current complexes,
[Er(OArMe)2Cl(thf)2]·PhMe14c has a monomeric structure closely
related to that of the alkynyl. A noteworthy feature of the
[Er(OArOMe)2(CCPh)(thf)2]·0.25C6H14 structure is the orientation
of the aryl rings of the two OArOMe ligands approximately perpen-
dicular to the basal plane, such that two of the But groups occupy
the vacant coordination space trans to the CCPh ligand. Fur-
thermore, the remaining two But groups protrude above the ErO4
plane and cradle the Er–C≡C linkage of the alkynyl ligand limiting
access to the Ln–C bond. The Er–C≡CPh linkage is near linear
175(1)◦, and the molecule has pseudo-C2 symmetry about the Er–
C vector. The Er–C distance is comparable to those of other ter-
minal lanthanoid alkynide complexes e.g. [Sm(Cp*)2(CCPh)(thf)]
(a) Reactions of lanthanoid metals with Hg(C6F5)2 and HOArOMe
[Yb(OArOMe)2(thf)3]. Ytterbium metal (1.38 g, 8.0 mmol),
Hg(C6F5)2 (1.01 g, 2.0 mmol) and HOArOMe (0.95 g, 4.0 mmol) were
stirred in thf (35 ml) for 4 d at room temperature. The reaction
mixture was filtered and the yellow filtrate was concentrated to
10 ml yielding bright yellow microcrystalline [Yb(OArOMe)2(thf)3]
(yield 1.10 g, 65%) (Found: C, 58.79; H, 8.67; Yb 19.31.
C42H70O7Yb (860.04) requires: C, 58.65; H, 8.20; Yb 20.12%).
IR (m/cm−1) 1598m, 1408vs, 1348s, 1274vs, 1253s, 1215vs, 1192s,
1172m, 1068vs, 1027s, 933w, 916w, 889m, 863m, 842w, 819m, 796s,
781m. 1H NMR (D8-thf, 298 K): d 6.59, s, 4H, H3,5; 3.60, s, 6H,
OCH3; 1.47, s, 36H, But. (CD3CN, 298 K): 6.57, s, 4H, H3,5;
3.64, br m, 12H, thf; 3.62, s, 6H, OCH3; 1.80, br m, 12H, thf;
1.40, s, 36H, But. Vis/near IR (thf: kmax/nm (e/dm3 mol−1 cm−1):
350 (799).
26a
26b
˚
˚
(2.50(1) A),
[Sm(HB(Me2pz)3(CCPh)] (2.494(9) A),
and
[La(L)(CCPh)(l-CCPh)]2 (L = Me2TACN(CH2)2NBut; 2.655(2),
26c
˚
2.674(2) A) after accounting for coordination number and
ionic radii differences.13 Similarly the Er–O(OH) distances are
marginally longer than those of [Yb(OArBu)2(l-OH)(thf)2]3e as
expected for the larger Er3+.13 The Er–O(OArOMe) distances
show a slight elongation for the alkynyl complex whereas those
of the hydroxyl complex span Er–O(OAr) for five coordinate
[Er(OArMe)2Cl(thf)2]·PhMe (2.097(5) A) and [Er(OAr)3(thf)2]
14c
˚
i
27
˚
(Ar = C6H3-2,6-Pr 2; 2.072(10)–2.090(10) A).
[Sm(OArOMe)2(thf)3]. Samarium metal (4.5 g, 30.0 mmol),
Hg(C6F5)2 (3.21 g, 6.0 mmol) and HOArOMe (2.84 g, 12.0 mmol)
were stirred in thf (100 ml) for 2 d at room temperature. The
reaction mixture was filtered and the brown filtrate was evaporated
to dryness. Treatment of the residue with diethyl ether (60 ml)
gave a dark solid and a yellow solution. The dark solid was
recrystallised from thf–hexanes (1 : 2, 15 ml) yielding dark brown
rods of [Sm(OArOMe)2(thf)3] (yield 0.41 g, 8%) (Found: C, 60.24;
H, 8.40; Sm 17.58. C42H70O7Sm (837.36) requires: C, 60.24; H,
Conclusions
We have shown that the use of sterically hindered aryloxide ligands
in redox transmetallation-ligand exchange syntheses of lanthanoid
complexes can influence the outcomes of these reactions. Thus, for
very crowded systems, mixed-ligand complexes such as LnL2R can
be the end point rather than progression through to LnL3 species.
Whilst the products with R = C6F5 proved to be unstable with
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8.43; Sm 17.96%). IR (m/cm−1): 1597m, 1408vs, 1345m, 1275vs,
1252m, 1214s, 1193m, 1173m, 1068s, 1033s, 933w, 919w, 892w,
863m, 842w, 819m, 794s, 782m. 1H NMR (D8-thf, 298 K): d 0.25, s,
6H, OCH3; −0.41, br s, 36H, But, −1.21, s, 4H, H3,5. Vis/near IR
(thf: kmax/nm (e/dm3 mol−1 cm−1)): 518 (200), 428 (420).
clear green–yellow solution that deposited a pale blue crystalline
solid on standing (yield 0.10 g). IR (m/cm−1) 1600w, 1407s, 1256s,
1
1245s, 1213s, 1170w, 1154w, 1114w, 1068s, 825s, 800s, 772w. H
NMR (CD3CN, 298 K): d 14.0*, s, H3,5; 12.0, br m; 6.70*, s,
OCH3; 6.0, br m; 3.60* br s, thf; 1.80*, br s, thf; −0.1*, br s, But;
−2.5, br m (* peaks matching [Nd(OArOMe)3(thf)]·thf, see below).
[Sm(OArOMe)3(thf)]·thf. The yellow filtrate from above was
evaporated to dryness and the residue was recrystallised from
thf–hexanes (100 ml, 1 : 3) and afforded bright yellow crystals
of [Sm(OArOMe)3(thf)]·thf (yield 2.55 g, 64%) (Found: Sm 14.67.
Attempted reaction with Er. Erbium metal (0.50 g, 3.0 mmol),
Hg(C6F5)2 (0.80 g, 1.5 mmol) and HOArOMe (0.71 g, 3.0 mmol)
were stirred in thf (30 ml) for 5 d at room temperature. The
solution was filtered and the filtrate was concentrated to 5 ml.
Addition of hexanes (20 ml) and filtration gave a clear pink
solution that deposited large pink crystals of [Er3(OArOMe)4(l2-
F)3(l3-F)2(thf)4]·thf·0.5C6H14 (yield 0.19 g, 10%) (Found: C, 52.72;
H, 7.21; Er 24.90. C83H139Er3F5O13 (1941.78) requires: C, 51.34;
H, 7.33; Er, 24.90%). IR (m/cm−1) 1600w, 1411vs, 1299w, 1266s,
1215vs, 1176w, 1154w, 1114w, 1068s, 1019m, 923w, 891w, 863w,
832s, 804m, 773w. The filtrate after isolation of the erbium
complex was evaporated to dryness and examined by mass
spectroscopy which showed the presence of HOArOMe (m/z
236) and fluorocarbon compounds, e.g. m/z 334 (C12F10+), 315
1
C53H85O8Sm (1000.60) requires: Sm 15.03%). IR, H NMR and
Vis/near IR spectra were identical with those of the product from
(b), see below.
Reaction of [Sm(OArOMe)2(thf)3] with Hg(C6F5)2. A mixture of
[Sm(OArOMe)2(thf)3] (0.08 g, 0.1 mmol) and Hg(C6F5)2 (0.03 g,
0.06 mmol) was dissolved in C6D6 (0.5 ml) and thf (0.1 ml).
The initially brown solution rapidly turned yellow and Hg was
deposited. 19F NMR: d −124.6, br m, 2F, o-F; −158.3, br m, 1F,
p-F; −164.8, br m, 2F, m-F ppm (Sm(OArOMe)2(C6F5)(thf)n), in
addition to minor peaks attributable to Hg(C6F5)2 and C6F5H
(trace). After 11 days at room temperature, the resonances of
Sm(OArOMe)2(C6F5)(thf)n had reduced in intensity by 50% (relative
to the Hg(C6F5)2) and new peaks were observed at −150.8, 2F,
F3,6; −163.8, 2F, F4,5; ppm (tetrafluorobicyclo[2.2.2]octatriene)17
in addition to other minor unidentified products (d −145.5, q;
−149.5, m; −151.3, m; −153.7, m; −154.6, m; −159.2, t; −163.0,
m; −164.0, m; ppm).
[Yb(OArOMe)2]. [Yb(OArOMe)2(thf)3] (1.18 g, 1.4 mmol), was
stirred in Et2O (50 ml) for 5 h with gentle warming. The resulting
suspended red solid was collected by filtration, washed with Et2O
anddried under vacuumfor 3h yieldingbright red microcrystalline
[Yb(OArOMe)2] (yield 0.76 g, 86%) (Found: C, 55.03; H, 7.13;
Yb 26.73. C30H46O4Yb (643.73) requires: C, 55.97; H, 7.20; Yb
26.88%). IR (m/cm−1) 1594w, 1410vs, 1350s, 1303vs, 1277s, 1245s,
1202s, 1174s, 1068w, 1024vs, 1008vs, 923m, 890m, 872m, 826vs,
798vs. 1H NMR (CD3CN, 298 K): d 6.59, s, 4H, H3,5; 3.63, s, 6H,
OCH3; 1.47, s, 36H, But (resonances attributable to trace amounts
(<5%) of Et2O were also observed in the NMR spectra of several
samples despite extended drying under vacuum).
(C12F9 ), 296 (C12F8 ), 168 (C6F5H+).
+
+
Attempted reaction with Y. Yttrium metal (0.27 g, 3.0 mmol),
Hg(C6F5)2 (0.80 g, 1.5 mmol) and HOArOMe (0.71 g, 3.0 mmol) were
stirred in thf (30 ml) for 14 d at room temperature. The solution
was filtered and the yellow filtrate was concentrated. Addition
of hexanes (40 ml) and filtration gave a clear yellow solution
that deposited a pale colourless crystalline solid on standing
(yield 0.23 g) (Found: Y, 13.24. C45H69O6Y ([Y(OArOMe)3] (794.95)
requires: Y 11.18%). IR (m/cm−1) 1600w, 1411vs, 1299w, 1266s,
1215vs, 1176w, 1154w, 1068vs, 1019m, 923w, 891w, 863w, 832w,
1
804m, 773w. H NMR (C6D6, 298 K): d 7.13, s; 7.07, s; 3.79, s;
3.59, s; 3.50, s; 1.76, s; 1.56, s; 1.36, s.
(b) Reactions of lanthanoid metals with Hg(CCPh)2 and HOArOMe
[Yb(OArOMe)2(thf)3]. Ytterbium metal (0.52 g, 3.0 mmol),
Hg(CCPh)2 (0.40 g, 1.0 mmol) and HOArOMe (0.47 g, 2.0 mmol)
were stirred in thf (20 ml) for 5 d at room temperature. The reaction
mixture was treated as in (a) above yielding the title complex (yield
0.46 g, 56%). 1H NMR and Vis/near IR spectra were identical with
those reported in (a), see above.
[Yb(OArOMe)2]·0.5PhMe. [Yb(OArOMe)2(thf)3]
(0.78
g,
0.90 mmol), was stirred in PhMe (30 ml) for 2 h at room
temperature. The resulting suspended red–orange solid was
collected by filtration, washed twice with PhMe and dried under
vacuum for 3 h yielding red–orange [Yb(OArOMe)2]·0.5PhMe
(yield 0.60 g, 92%) (Found: Yb 25.50. C33.5H50O4Yb (689.79)
requires: Yb 25.09%). IR (m/cm−1) 1603w, 1407vs, 1350s, 1301vs,
1277s, 1244s, 1204s, 1173s, 1068w, 1023vs, 1007vs, 922m, 891m,
[La(OArOMe)3(thf)]·thf. Lanthanum metal (0.83 g, 6.0 mmol),
Hg(CCPh)2 (1.21 g, 3.0 mmol) and HOArOMe (1.42 g, 6.0 mmol)
were stirred in thf (30 ml) for 12 days at room temperature.
The solution was filtered and the filtrate was concentrated to
5 ml. Addition of hexanes (30 ml) gave colourless needles of
[La(OArOMe)3(thf)]·thf on standing (yield 1.51 g, 76%) (Found: C,
64.31; H, 8.96; La 13.50. C53H85O8La (989.14) requires: C, 64.36;
H, 8.66; La 14.04%). IR (m/cm−1) 1602m, 1569w, 1404vs, 1354m,
1295w, 1256s, 1234s, 1202vs, 1114w, 1069vs, 1017s, 933w, 866s,
1
872m, 825vs, 798vs, 789m, 694w. H NMR (CD3CN, 298 K): d
7.35–7.05, m, 4H, PhMe; 6.58, s, 4H, H3,5; 3.62, s, 6H, OCH3;
2.32, s, 2.4H, PhMe; 1.40, s, 36H, But (integration of the PhMe
resonances indicated the composition [Yb(OArOMe)2]·0.8PhMe
for the NMR sample).
1
844m, 820s, 791vs, 775 (sh) s. H NMR (D8-PhMe, 298 K): d
6.94, s, 6H, H3,5; 3.65, m, 8H, a-thf; 3.56, s, 9H, OCH3; 1.54, s,
54H, But; 1.36, m, 8H, b-thf. 13C NMR (D8-PhMe, 298 K): d
157.3, C1; 150.8, C4; 137.5, C2,6; 111.1, C3,5; 69.2, a-thf; 55.2,
OCH3; 35.2, CMe3; 32.1, CH3; 25.6, b-thf. MS(EI): m/z 845 [0.6%,
La(OArOMe)2(HOArOMe)+]; 610 [3, La(OArOMe)(HOArOMe)+]; 594
Attempted reaction with Nd. Neodymium metal (0.58 g,
4.0 mmol), Hg(C6F5)2 (0.80 g, 1.5 mmol) and HOArOMe (0.71 g,
3.0 mmol) were stirred in thf (30 ml) for 14 d at room temperature.
The solution was filtered and the brown–yellow filtrate was
concentrated. Addition of hexanes (40 ml) and filtration gave a
+
+
[0.4, La(OArOMe)2 − CH3 ]; 577 [0.4, La(OArOMe)2 − 2CH4 ]; 422
808 | Dalton Trans., 2006, 802–812
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[0.2, La(OArOMe
)
2+]; 374 [0.1, La(OArOMe)+]; 236 [63, HOArOMe+];
60%) (Found: C, 62.02; H, 8.41; Sm, 15.69. C49H79O8Sm (946.51)
requires: C, 62.18; H, 8.41; Sm, 15.89%). IR (m/cm−1): 1600s,
1562w, 1405vs, 1355s, 1294m, 1253s, 1210vs, 1113m, 1094m,
1067s, 1040s, 1016w, 996w, 936w, 890mw, 861s, 820s, 793vs, 774s.
1H NMR (CD3CN, 298 K): d 7.44, s, 6H, H3,5; 4.07, s, 9H, OCH3;
3.44, s, 4H, CH2(dme); 3.27, s, 6H, CH3(dme); 1.03, s, 54H, But;
(C6D6, 298 K): d 7.98, s, 6H, H3,5; 5.23, br s, 6H, CH3(dme);
4.07, s, 9H, OCH3; 1.03, s, 54H, But; −5.55, br s, 4H, CH2(dme).
Vis/near IR (thf: kmax/nm (e/dm3 mol−1 cm−1)) 1441 (18), 1380 (4),
1343 (12), 1268 (4), 1209 (13), 1064 (8), 971 (2), 938 (1), 348 (809).
3
+
+
221 [96, HOArOMe − CH3 ]; 57 [100, C4H9 ].
[Pr(OArOMe)3(thf)]·thf. Following the procedure for La above,
praseodymium metal (0.85 g, 6.0 mmol), Hg(CCPh)2 (1.21 g,
3.0 mmol) and HOArOMe (1.42 g, 6.0 mmol) gave yellow–green
plates of [Pr(OArOMe)3(thf)]·thf (yield 1.47 g, 74%) (Found: C,
64.11; H, 8.71; Pr 13.91. C53H85O8Pr (991.14) requires: C, 64.23;
H, 8.64; Pr 14.22%). IR (m/cm−1) 1598m, 1570w, 1409vs, 1350m,
1299w, 1240vs, 1209vs, 1112w, 1064vs, 1043s, 1009m, 938w, 922w,
866m, 847m, 824s, 800vs, 773m. 1H NMR (CD3CN, 298 K):
d 16.91, s, 6H, H3,5; 8.10, s, 9H, OCH3; 3.62, m, 8H, a-thf;
1.79, m, 8H, b-thf; 1.01, s, 54H, But. MS(EI): m/z 847 [0.2%,
Pr(OAr)2(HOArOMe)+]; 612 [1.5, Pr(OArOMe)(HOArOMe)+]; 596 [0.1,
MS(EI): m/z 857 [10%, Sm(OArOMe)3 ]; 622 [19, Sm(OArOMe)2 ];
+
+
+
+
606 [2, Sm(OArOMe)2 − CH4 ]; 590 [2, Sm(OArOMe)2 − 2CH4 ];
387 [4, Sm(OArOMe)+]; 371 [12, Sm(OArOMe) − CH3 ]; 355 [3,
+
Sm(OArOMe) − 2CH4 ]; 236 [8, HOArOMe+]; 221 [10, HOArOMe
−
+
Pr(OArOMe)2 − CH3 ]; 580 [0.1, Pr(OArOMe)2 − C2H7 ]; 377 [0.1,
+
+
+
+
CH3 ]; 57 [100, C4H9 ].
Pr(OArOMe) + H+]; 361 [Pr(OArOMe) − CH3 ]; 236 [60, HOArOMe+];
+
221 [100, HOArOMe − CH3 ]; 57 [26, C4H9 ].
[Gd(OArOMe)3(thf)]·thf. Following the procedure for La above,
gadolinium metal (0.94 g, 6.0 mmol), Hg(CCPh)2 (1.21 g,
3.0 mmol) and HOArOMe (1.42 g, 6.0 mmol) gave colourless
crystals of [Gd(OArOMe)3(thf)]·thf (yield 1.45 g, 72%) (Found:
C, 63.08; H, 8.01; Gd 15.23. C53H85GdO8 (1007.49) requires: C,
63.18; H, 8.50; Gd 15.61%). IR (m/cm−1) 1599m, 1570w, 1409vs,
1348m, 1299w, 1240s, 1210vs, 1113w, 1064s, 1042w, 1002m, 938w,
923w, 893w, 867m, 827vs, 802s, 772m. MS(EI): m/z 863 [3%,
+
+
[Nd(OArOMe)3(thf)]·thf. Following the procedure for La above,
neodymium metal (0.87 g, 6.0 mmol), Hg(CCPh)2 (1.21 g,
3.0 mmol) and HOArOMe (1.42 g, 6.0 mmol) gave pale blue plates
of [Nd(OArOMe)3(thf)]·thf (yield 0.92 g, 46%) (Found: C, 64.26; H,
8.92; Nd 14.50. C53H85NdO8 (994.48) requires: C, 64.01; H, 8.62;
Nd 14.50%). IR (m/cm−1) 1598m, 1409vs, 1350m, 1298w, 1240s,
1210vs, 1112w, 1064s, 1008w, 922w, 893w, 867w, 825s, 800s, 772w.
1H NMR (CD3CN, 298 K): d 14.00, s, 6H, H3,5; 6.72, s, 9H, OCH3;
3.63, br s, 8H, a-thf; 1.81, br s, 8H, b-thf; −0.10, br s, 54H, But;
(C6D6, 298 K): d 15.09, s, 6H, H3,5; 6.90, s, 9H, OCH3; −1.25, s,
54H, But (signals due to thf were not located in the region 100
to −100 ppm). Vis/near IR (thf: kmax/nm (e/dm3 mol−1 cm−1))
896 (1), 873 (1), 862 (1), 811 (2), 798 (3), 764 (1), 603 (10), 584
(28), 580 (29), 526 (5), 519 (4), 396 (25). MS(EI): m/z 849 [4%,
Gd(OArOMe)3 ]; 628 [3, Gd(OArOMe)2 ]; 612 [2, Gd(OArOMe)2 −
+
+
CH4 ]; 596 [4, Gd(OArOMe)2 − 2CH4 ]; 580 [2, Gd(OArOMe)2 −
+
+
3CH4 ]; 564 [2, Gd(OArOMe)2 − 4CH4 ]; 393 [0.2, Gd(OArOMe)+];
+
+
236 [92, HOArOMe+]; 221 [100, HOArOMe − CH3 ]; 57 [76, C4H9 ].
+
+
[Ho(OArOMe)3(thf)]·thf. Following the procedure for La above,
holmium metal (0.99 g, 6.0 mmol), Hg(CCPh)2 (1.21 g, 3.0 mmol)
and HOArOMe (1.42 g, 6.0 mmol) gave pale yellow crystals of
[Ho(OArOMe)3(thf)]·thf (yield 1.30 g, 64%) (Found: Ho 16.73.
C53H85HoO8 (1015.17) requires: Ho 16.25%). IR (m/cm−1) 1598m,
1569w, 1410s, 1296w, 1245s, 1211vs, 1113w, 1063s, 1006m, 921w,
Nd(OArOMe)3 ]; 614 [9, Nd(OArOMe)2 ]; 598 [1, Nd(OArOMe)2 −
+
+
+
+
CH4 ]; 582 [2, Nd(OArOMe)2 − 2CH4 ]; 566, [0.4, Nd(OArOMe)2 −
3CH4 ]; 550 [0.2, Nd(OArOMe)2 − 4CH4 ]; 518 [0.2, Nd(OArOMe)2 −
+
+
6CH4 ]; 362 [0.4, Nd(OArOMe) − CH3 ]; 236 [50, HOArOMe+]; 221
861m, 827vs, 802s, 770m. MS(EI): m/z 870 [1%, Ho(OArOMe)3 ];
+
+
+
+
+
+
+
[66, HOArOMe − CH3 ]; 57 [100, C4H9 ].
635 [1, Ho(OArOMe)2 ]; 603 [0.2, Ho(OArOMe)2 − 2CH4 ]; 587 [0.2,
Ho(OArOMe)2 − 3CH4 ]; 571 [0.2, Ho(OArOMe)2 − 4CH4 ]; 236 [67,
+
+
[Sm(OArOMe)3(thf)]·thf. Following the procedure for La above,
samarium metal (0.38 g, 2.5 mmol), Hg(CCPh)2 (1.21 g, 3.0 mmol)
and HOArOMe (1.42 g, 6.0 mmol) gave yellow crystals of
[Sm(OArOMe)3(thf)]·thf (yield 1.26 g, 63%) (Found: C, 62.91; H,
8.42; Sm 14.61. C53H85O8Sm (1000.60) requires: C, 63.62; H,
8.56; Sm 15.03%). IR (m/cm−1) 1598m, 1570w, 1409vs, 1352m,
1298w, 1240s, 1210vs, 1112w, 1064s, 1043m, 1005m, 937w, 922w,
893w, 868m, 826s, 801s, 771m. 1H NMR (CD3CN, 298 K):
d 7.44, s, 6H, H3,5; 4.07, s, 9H, OCH3; 3.63, m, 8H, a-thf;
1.79, m, 8H, b-thf; 1.03, s, 54H, But. Vis/near IR (thf: kmax/nm
(e/dm3 mol−1 cm−1)) 1418 (23), 1321 (19), 1264 (1), 1198 (15), 1057
(3), 1042 (2), 971 (1), 928 (1), 346 (391). MS(EI): m/z 857 [3%,
HOArOMe+]; 221 [100, HOArOMe − CH3 ]; 57 [18, C4H9 ].
+
+
[Er(OArOMe)2(CCPh)(thf)2]. A mixture of erbium metal (1.0 g,
6.0 mmol), Hg(CCPh)2 (1.21 g, 3.0 mmol) and HOArOMe (1.42 g,
6.0 mmol) was stirred in thf (30 ml) for 10 d at room temperature.
The solution was filtered and the filtrate was concentrated to
10 ml. Addition of hexanes (30 ml) gave fine pink needles of
[Er(OArOMe)2(CCPh)(thf)2] on standing (yield 0.89 g, 50%) (Found:
C, 61.95; H, 8.24; Er 18.60. C46H67ErO6 (883.28) requires: C, 62.55;
H; 7.65; Er 18.94%). IR (m/cm−1) 2077w m(C≡C), 1596m, 1586w,
1483m, 1407s, 1296w, 1254s, 1245 s (sh), 1213vs, 1172w (sh), 1150w
(sh), 1115w, 1058s, 1011m, 943w, 892w, 864w, 825vs, 802vs, 781m,
775m, 760m, 694m. Vis/near IR (thf: kmax/nm (e/dm3 mol−1 cm−1))
513 (29), 486 (2), 399 (2), 379 (31), 365 (5), 356 (1).
Sm(OArOMe)3 ]; 622 [10, Sm(OArOMe)2 ]; 606 [1, Sm(OArOMe)2 −
+
+
CH4 ]; 590 [1, Sm(OArOMe)2 − 2CH4 ]; 387 [3, Sm(OArOMe)+]; 371
+
+
[10, Sm(OArOMe) − CH3 ]; 355 [3, Sm(OArOMe) − 2CH4 ]; 236 [70,
+
+
[Y(OArOMe)2(CCPh)(thf)2]. (a) A mixture of yttrium metal
(0.53 g, 6.0 mmol), Hg(CCPh)2 (1.21 g, 3.0 mmol) and HOArOMe
(1.42 g, 6.0 mmol) was stirred in thf (30 ml) for 5 d at room
temperature. The solution was filtered and the pale yellow filtrate
was concentrated to 10 ml. Addition of hexanes (15 ml) gave
colourless [Y(OArOMe)2(CCPh)(thf)2] on standing (yield 0.43 g,
27%) (Found: C, 68.01; H, 7.68; Y 10.50. C46H67O6Y (804.92)
requires: C, 68.64; H; 8.39; Y 11.04%). IR (m/cm−1) 2074w m(C≡C),
HOArOMe+]; 221 [100, HOArOMe − CH3 ]; 57 [97, C4H9 ].
+
+
[Sm(OArOMe)3(dme)]. [Sm(OArOMe)3(thf)]·thf
(1.50
g,
1.5 mmol) was dissolved in dme (40 ml) and stirred at
room temperature for 24 h. The solvent was removed and the
residue was recrystallised from hot 1 : 3 dme–hexanes (40 ml)
yielding yellow blocks of [Sm(OArOMe)3(dme)] which were washed
with hexanes and dried under vacuum for 3 h (yield 0.85 g,
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1596m, 1569w, 1483m, 1408vs, 1384s, 1297w, 1256s, 1243s (sh),
1213vs, 1198s (sh), 1173w (sh), 1151w (sh), 1115w, 1068s (sh),
1059vs, 1017m, 933w, 892w, 864s, 825vs, 802vs, 779m, 760m, 694m.
Reaction of [Lu(OArOMe)2(CCPh)(thf)2] with HOArOMe
.
A mix-
ture of [Lu(OArOMe)2(CCPh)(thf)2] (0.04 g, 0.04 mmol) and
HOArOMe (0.01 g, 0.04 mmol) was dissolved in C6D6 and the
reaction was monitored by 1H NMR spectroscopy. Over a period
of 30 days, resonances of the reactants decreased in intensity
and two new sets of peaks were observed. These corresponded
to Lu(OAr)3(thf) (d 7.04, s, 6H, H3,5; 3.55, s, 9H, OMe;
1.56, s, 54H, But; ppm in reasonable agreement with values for
[La(OArOMe)3(thf)]·thf (see above)) and PhCCH.
3
4
1H NMR (D8-thf, 298 K): d 7.35, dd, J = 8.1; J = 1.6 Hz,
2H, o-H(Ph); 7.25–7.00, m, 3H, m-,p-H(Ph); 6.64, s, 4H, H3,5;
3.61, s, 6H, OCH3; 1.53, s, 36H, But; (C6D6, 298 K): d 7.67, dd,
4
3J = 7.6; J = 1.6 Hz, 2H, o-H(Ph); 7.19, s, 4H, H3,5; 7.10–
6.85, m, 3H, m-,p-H(Ph); 3.86, s, 8H, a-thf; 3.60, s, 6H, OCH3;
1.74, s, 36H, But; 1.12, s, 8H, b-thf; 13C NMR (D8-thf, 298 K): d
157.5, ipso-C(OAr); 150.7, 4-C(OAr); 144.7, d, 1JYC = 80.7 Hz; a-
CCPh; 139.4, 2,6-C(OAr); 132.0, o-C(Ph); 128.6, m-C(Ph); 128.3,
Crystal and refinement data
2
ipso-C(Ph); 126.4, p-C(Ph); 111.1, 3,5-C(OAr); 103.4, d, JYC
=
For X-ray studies, representative single crystals for each complex
were mounted under argon in sealed Lindemann glass capillaries.
Single counter, four-circle diffractometer (Enraf Nonius CAD4
or Siemens/Nicolet R3m/V or Phillips PW1100) data sets were
15.4 Hz; b-CCPh; 55.4 OCH3; 36.2, C(CH3)3, 32.1 C(CH3)3. (b)
Following the procedure in (a), yttrium metal (0.53 g, 6.0 mmol),
Hg(CCPh)2 (1.21 g, 3.0 mmol) and HOArOMe (0.95 g, 4.0 mmol)
gave colourless needles of [Y(OArOMe)2(CCPh)(THF)2] (yield 1.0 g,
63%). Spectroscopic data were identical to those for the product
from (a).
˚
measured (MoKa k 0.71073 A, T as quoted) yielding N independent
reflections for each set. Data were corrected for absorption
and structures were refined by full-matrix least-squares with
anisotropic displacement parameters for the non-hydrogen atoms.
Hydrogen atoms were included in calculated positions unless
otherwise specified.
[Lu(OArOMe)2(CCPh)(thf)2]. A mixture of lutetium metal
(0.90 g, 4.5 mmol), Hg(CCPh)2 (1.21 g, 3.0 mmol) and HOArOMe
(0.95 g, 3.0 mmol) was stirred in thf (30 ml) for 25 d at room temper-
ature. The solution was filtered and the filtrate was concentrated
to 8 ml. Addition of hexanes (20 ml), followed by further concen-
tration gave colourless crystals of [Lu(OArOMe)2(CCPh)(thf)2] on
standing (yield 0.60 g, 34%) (Found: C, 60.55; H, 7.31; Lu 19.14.
C46H67LuO6 (890.99) requires: C, 62.01; H; 7.58; Lu 19.64%). IR
(m/cm−1) 2082w m(C≡C), 1596w, 1570w, 1483m, 1408vs, 1296w,
1255s, 1244 m (sh), 1213vs, 1173w (sh), 1153w (sh), 1115w, 1058s,
1010m, 935w, 892w, 864m, 826s, 803s, 782w, 774w, 756m, 693w.
1H NMR (D8-thf, 298 K): d 7.35, dd, 3J = 8.3; 4J = 1.3 Hz, 2H,
o-H(Ph); 7.17, t, 3J = 7.2 Hz, 2H, m-H(Ph); 7.09, tt, 3J = 7.3, 4J =
1.3 Hz, 1H, p-H(Ph); 6.67, s, 4H, H3,5; 3.61, s, 6H, OCH3; 1.54, s,
[Sm(OArOMe)2(thf)3]·thf. C46H78O8Sm, M = 909.5, monoclinic,
space group P21/n, a = 16.019(3), b = 15.340(3), c = 19.799(10)
◦
3
−3
˚
˚
A, b = 94.10(3) , V = 4853(3) A , Dc = 1.245 g cm , Z = 4, l =
1.26 mm−1; crystal: 0.13 × 0.23 × 0.35 mm; Tmin,max = 0.79, 0.85;
T ∼ 298 K, 2hmax = 50◦; N = 8407, No = 4127 (F > 4r(F)); R =
0.062, Rw = 0.078. Variata: Assignment of the oxygen of the lattice
thf was less secure than desired.
[Yb(OArOMe)2(thf)3]·thf. C46H78O8Yb, M = 932.2, monoclinic,
˚
space group P21/c, a = 9.827(5), b = 15.393(6), c = 31.677(8) A,
◦
3
−3
˚
b = 93.95(2) , V = 4780(3) A , Dc = 1.30 g cm , Z = 4, l =
1.99 mm−1; crystal: 0.22 × 0.28 × 0.17 mm; Tmin,max = 0.60, 0.72;
T ∼ 293 K, 2hmax = 56◦; N = 11499, No = 4874 (I > 3r(I)); R =
0.047, Rw = 0.045.
3
4
36H, But; (C6D6, 298 K): d 7.77, dd, J = 8.3; J = 1.3 Hz, 2H,
o-H(Ph); 7.22, s, 4H, H3,5; 7.12, t, 3J = 7.6 Hz, 2H, m-H(Ph); 6.98,
tt, 3J = 7.5, 4J = 1.3 Hz, 1H, p-H(Ph); 3.93, s, 8H, a-thf; 3.62, s,
6H, OCH3; 1.75, s, 36H, But; 1.12, s, 8H, b-thf; 13C NMR (D8-thf,
298 K): d 158.3, ipso-C(OAr); 153.8, a-CCPh; 150.5, 4-C(OAr);
139.5, 2,6-C(OAr); 132.0, o-C(Ph); 128.6, m-C(Ph); 128.0, ipso-
C(Ph); 126.6, p-C(Ph); 111.1, 3,5-C(OAr); 106.3, b-CCPh; 55.3
OCH3; 36.2, C(CH3)3, 32.2 C(CH3)3.
[Er3(OArOMe)4(l2-F)3(l3-F)2(thf)4]·thf·0.5C6H14.
C83H139Er3-
F5O13, M = 1941.7, monoclinic, space group P21/c, a = 15.049(2),
◦
3
˚
˚
b = 19.045(3), c = 32.230(6) A, b = 95.77(3) , V = 9191(3) A ,
Dc = 1.39 g cm−3, Z = 4, l = 2.778 mm−1; crystal: 0.06 × 0.12 ×
0.19 mm; Tmin,max = 0.50, 0.62; T ∼ 153 K, 2hmax = 50◦; N =
16170, No = 9509 (I > 2r(I)); R = 0.069, Rw = 0.146. Variata:
The thf ligand O(9), C(61)–C(64) and the But group C(57)–C(60)
were disordered over two positions, the minor components refined
with restrained geometry and isotropic displacement parameters.
Lattice thf and hexane, the latter with restrained geometry, were
refined with isotropic displacement parameters.
[Yb(OArOMe)2(CCPh)(thf)2]. A mixture of Hg(CCPh)2 (0.30 g,
0.75 mmol) and [Yb(OArOMe)2] (0.97 g, 1.5 mmol) was stirred in thf
(25 ml) for 28 days, during which time the solution changed from
yellow to orange and Hg was deposited. The reaction mixture was
filtered and the filtrate was reduced to 5 ml. Addition of hexanes
(25 ml) yielded an orange precipitate that was recrystallised from
thf giving orange needles of [Yb(OArOMe)2(CCPh)(thf)2] which
were washed with thf and dried under vacuum for 4 h (yield
0.64 g, 46%) (Found: C, 61.87; H, 7.69; Yb, 19.10. C46H67O6Yb
(865.43) requires: C, 62.14; H, 7.60; Yb, 19.46%). IR (m/cm−1):
2079w m(C≡C), 1598w, 1568w, 1407s, 1297w, 1255br s, 1213vs,
1173m, 1149m, 1115w, 1059s, 1011m, 933w, 892w, 864m, 826s,
802s, 780m, 758m, 724w, 693w. 1H NMR (D8-thf, 298 K): d 25.5, s,
2H, o-H(Ph); 14.7, s, 2H, m-H(Ph); 13.0, s, 1H, p-H(Ph); −6.6, br s,
36H, But; −9.5, s, 6H, OCH3; −20.7, s, 4H, H3,5. Vis/near IR (thf:
kmax/nm (e/dm3 mol−1 cm−1)) 1013 (2), 979 (6), 955 (5), 918 (14),
884(5) 396 (236).
[Nd(OArOMe)3(thf)]·thf. C53H85NdO8, M = 994.5, monoclinic,
˚
space group P21/c, a = 16.824(6), b = 16.409(9), c = 19.187(5) A,
◦
3
−3
˚
b = 90.97(2) , V = 5296(4) A , Dc = 1.247 g cm , Z = 4, l =
1.01 mm−1; crystal: 0.12 × 0.55 × 0.40 mm; T ∼ 298 K, 2hmax
=
50◦; N = 9299, No = 4463 (I > 3r(I)); R = 0.045, Rw = 0.045.
[Ho(OArOMe)3(thf)]·thf. C53H85HoO8, M = 1015.2, mono-
clinic, space group P21/c, a = 16.852(5), b = 16.437(6), c =
◦
3
−3
˚
˚
19.084(10) A, b = 90.94(4) , V = 5285(4) A , Dc = 1.276 g cm ,
Z = 4, l = 1.55 mm−1; crystal: 0.10 × 0.27 × 0.55 mm; Tmin,max
=
0.67, 0.91; T ∼ 298 K, 2hmax = 50◦; N = 9277, No = 4933
810 | Dalton Trans., 2006, 802–812
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©

View Article Online
(I > 3r(I)); R = 0.059, Rw = 0.056. Variata: The Nd and Ho
compounds are isomorphous; in both the But groups C(22n),
C(26n) were modelled as rotationally disordered over two sites
with constrained geometries. Assignment of the lattice thf oxygen
was less secure than desired.
Hitchcock, S. A. Holmes, M. F. Lappert, P. MacKinnon and R. H.
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Wiley-VCH, Germany, Weinheim, 2002, ch. 7, p. 139.
[Sm(OArOMe)3(dme)]. C49H79O8Sm, M = 946.5, monoclinic,
˚
space group P21/c, a = 17.111(5), b = 18.392(3), c = 17.722(8) A,
◦
3
−3
˚
b = 116.88(3) , V = 4974(3) A , Dc = 1.264 g cm , Z = 4, l =
1.23 mm−1; crystal: 0.42 × 0.30 × 0.40 mm; Tmin,max = 0.61, 0.74;
T ∼ 298 K, 2hmax = 50◦; N = 8740, No = 4483 (I > 3r(I)); R =
0.056, Rw = 0.069. Variata: The OMe group O(34), C(341) and
associated ring were modelled as disordered, the atoms refined
with isotropic thermal parameters and rigid body constraint.
[Er(OArOMe)2(CCPh)(thf)2]·0.25C6H14. C47.5H70.5ErO6,
M
=
˚
904.9, hexagonal, space group P61, a = 28.49(3), c = 10.21(1) A,
3
−3
−1
˚
V = 7177(17) A , Dc = 1.256 g cm , Z = 6, l = 1.80 mm ; crystal:
0.20 × 0.08 × 0.25 mm; Tmin,max = 0.68, 0.87; T ∼ 298 K, 2hmax
=
50◦; N = 3347, No = 2266 (I > 3r(I)); R = 0.048, Rw = 0.041
(space group P61 (preferred)). Solvent residues were modelled in
terms of a hexane molecule disposed about the symmetry axis.
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J. Organomet. Chem., 1979, 182, 121.
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Yanovsky and Y. T. Struchkov, Organometallics, 1995, 14, 2127.
10 M. L. Cole, G. B. Deacon, P. C. Junk and K. Konstas, Chem. Commun.,
2005, 1581.
11 (a) A. M. Bond, G. B. Deacon and R. H. Newnham, Organometallics,
1986, 5, 2312; (b) R. G. Finke, S. R. Keenan, D. A. Schiraldi and P. L.
Watson, Organometallics, 1986, 5, 598.
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13 R. D. Shannon, Acta Crystallogr., Sect. A, 1976, 32, 751.
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Chem., 1995, 34, 5; (b) Z. Hou, A. Fujita, T. Yoshimura, A. Jesorka, Y.
Zhang, H. Yamazaki and Y. Wakatsuki, Inorg. Chem., 1996, 35, 7190;
(c) Y. M. Yao, Q. Shen, Y. Zhang, M. Q. Que and J. Sun, Polyhedron,
2001, 20, 3201.
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J. W. Ziller, R. N. R. Broomhall-Dillard and W. J. Evans, Angew. Chem.,
Int. Ed., 1997, 36, 133; (b) W. J. Evans, N. T. Allen and J. W. Ziller, J. Am.
Chem. Soc., 2000, 122, 11749; (c) M. N. Bochkarev, I. L. Fedushkin,
S. Dechert, A. A. Fagin and H. Schumann, Angew. Chem., Int. Ed.,
2001, 40, 3176; (d) M. C. Cassani, Y. K. Gunko, P. B. Hitchcock,
M. F. Lappert and F. Laschi, Organometallics, 1999, 18, 5539; (e) M. C.
Cassani, D. J. Duncalf and M. F. Lappert, J. Am. Chem. Soc., 1998, 120,
12958.
16 S. C. Cohen and A. G. Massey, Adv. Fluorine Chem., 1970, 6, 83.
17 L. Maron, E. Werkeme, L. Perrin, O. Eisenstein and R. A. Andersen,
J. Am. Chem. Soc., 2005, 127, 279.
18 (a) Q. Shen, M. Qi and Y. Lin, J. Organomet. Chem., 1990, 399, 247;
(b) J. Jin, S. Jin and W. Chen, Polyhedron, 1992, 11, 2873; (c) Y. Cheng,
G. X. Jin, Q. Shen and Y. Lin, J. Organomet. Chem., 1992, 631, 94;
(d) W. P. Kretschmer, J. H. Teuben and S. I. Troyanov, Angew. Chem.,
Int. Ed., 1998, 37, 88.
[Er(OArOMe)2(OH)(thf)]2·2thf. C76H126Er2O14
M
= 1598.4,
monoclinic, space group P21/c, a = 9.894(2), b = 25.581(8), c =
◦
3
−3
˚
˚
15.606(8) A, b = 91.63(4) , V = 3948(3) A , Dc = 1.344 g cm ,
Z = 2 (dimers), l = 2.17 mm−1; crystal: 0.23 × 0.20 × 0.23 mm;
Tmin,max = 0.63, 0.69; T ∼ 298 K, 2hmax = 50◦; N = 6936, No =
4770 (I > 3r(I)); R = 0.037, Rw = 0.049. The hydroxyl H atom
was located and refined in (x, y, z, Uiso).
CCDC reference numbers 281263–281269 and 282031.
For crystallographic data in CIF or other electronic format see
DOI: 10.1039/b511609k
Acknowledgements
This research was supported by the Australian Research Council
and through an Australian Postgraduate Research Award to
S. C. H.
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