Organoamido- and aryloxo-lanthanoids, 19. Synthesis and structures of cisoid and transoid bis(1,2-dimethoxyethane)bis(η2- pyrazolato)lanthanoid(II) complexes

Article abstract of DOI:10.1002/(sici)1099-0682(199905)1999:5<751::aid-ejic751>3.0.co;2-5

The complexes [Yb(bind)₂(DME)₂], [Yb(MePhpz)₂(DME)₂], [Yb(azin)₂(DME)₂], and [Eu(Ph₂pz)₂(DME)₂] (bindH = 4,5-dihydro-2H- benz[g]indazole; MePhpzH = 3-methyl-5-phenylpyrazole; azinH = 7-azaindole; Ph₂pzH = 3,5-diphenylpyrazole; DME = 1,2-dimethoxyethane) have been prepared by redox transmetallation between ytterbium or europium metal and the corresponding thallium(I) pyrazolate in tetrahydrofuran (THF) in the presence of mercury metal, followed by work up with DME. The thallium reagents were obtained by treatment of the appropriate pyrazole with thallium(I) ethoxide. Both [Yb(Ph₂pz)₂(DME)₂] and [Sm(Ph₂pz)₂(DME)₂] have been prepared by metathesis from LnI₂(THF)₂ and K(Ph₂pz) in THF, whilst the former has also been obtained by redox transmetallation from [Hg(Ph₂pz)₂] and ytterbium metal and by reaction of 3,5-diphenylpyrazole with Yb(C₆F₅)₂, and the latter from protolysis of [Sm{N(SiMe₃)₂}2(THF)₂] with Ph₂pzH, followed in each case by crystallisation of the crude product from DME. Europium(II) 3,5-di-tert-butylpyrazolate was synthesised by a redox transmetallation/ligand exchange reaction between europium metal chunks, diphenylmercury(II), and 3,5-di-tert-butylpyrazole (tBu₂pzH) in the presence of mercury metal in THE and [Eu(tBu₂pz)₂(DME)₂] was isolated on crystallisation of the crude product from DME. The X-ray crystal structures of [Ln(L)₂(DME)₂] (Ln =Yb, L = bind or azin; Ln = Eu or Sm, L = Ph₂pz; Ln = Eu, L = tBu₂pz), each of a different crystallographic form, reveal eight- coordinate lanthanoid complexes with two η²-pyrazolate and two chelating DME ligands, but the structures differ in the relationship (cisoid or transoid) between the pyrazolate ligands. Thus cen-Ln-cen (cen = centre of the N-N bond) angles of 106.7°[Yb(bind)₂(DME)₂] (3a), 141.4°[Yb(azin)₂(DME)₂] (3c), 142.2°[EU(Ph₂pz)₂(DME)₂] (4a), 107.4°[Eu(tBu₂pz)₂(DME)₂] (4b), and 102.1°[Sm(Ph₂pz)₂(DME)₂] (5) are observed.

Full text of DOI:10.1002/(sici)1099-0682(199905)1999:5<751::aid-ejic751>3.0.co;2-5

FULL PAPER
Organoamido- and Aryloxo-Lanthanoids, 19[°]
Synthesis and Structures of cisoid and transoid
Bis(1,2-dimethoxyethane)bis(η2-pyrazolato)lanthanoid(II) Complexes
Glen B. Deacon,*[a] Ewan E. Delbridge,[a] Brian W. Skelton,[b] and Allan H. White[b]
Keywords: Lanthanide(II) complexes / Ytterbium / Europium / Samarium / Redox transmetallation / Thallium /
Diphenylmercury
The complexes [Yb(bind)2(DME)2], [Yb(MePhpz)2(DME)2],
[Yb(azin)2(DME)2], and [Eu(Ph2pz)2(DME)2] (bindH = 4,5-
Europium(II) 3,5-di-tert-butylpyrazolate was synthesised by
a redox transmetallation/ligand exchange reaction between
europium metal chunks, diphenylmercury(II), and 3,5-di-
dihydro-2H-benz[g]indazole; MePhpzH
phenylpyrazole; azinH 7-azaindole; Ph2pzH
diphenylpyrazole; DME = 1,2-dimethoxyethane) have been metal in THF, and [Eu(tBu2pz)2(DME)2] was isolated on
=
3-methyl-5-
=
= 3,5- tert-butylpyrazole (tBu2pzH) in the presence of mercury
prepared by redox transmetallation between ytterbium or
europium metal and the corresponding thallium(I) pyrazolate
in tetrahydrofuran (THF) in the presence of mercury metal,
followed by work up with DME. The thallium reagents were
obtained by treatment of the appropriate pyrazole with
crystallisation of the crude product from DME. The X-ray
crystal structures of [Ln(L)2(DME)2] (Ln =Yb, L = bind or azin;
Ln = Eu or Sm, L = Ph2pz; Ln = Eu, L = tBu2pz), each of a
different crystallographic form, reveal eight-coordinate
lanthanoid complexes with two η2-pyrazolate and two
chelating DME ligands, but the structures differ in the
relationship (cisoid or transoid) between the pyrazolate
ligands. Thus cen–Ln–cen (cen = centre of the N–N bond)
angles of 106.7° [Yb(bind)2(DME)2] (3a), 141.4° [Yb(azin)2-
(DME)2] (3c), 142.2° [Eu(Ph2pz)2(DME)2] (4a), 107.4°
[Eu(tBu2pz)2(DME)2] (4b), and 102.1° [Sm(Ph2pz)2(DME)2] (5)
are observed.
thallium(I) ethoxide.
Both [Yb(Ph2pz)2(DME)2] and
[Sm(Ph2pz)2(DME)2] have been prepared by metathesis from
LnI2(THF)2 and K(Ph2pz) in THF, whilst the former has also
been obtained by redox transmetallation from [Hg(Ph2pz)2]
and ytterbium metal and by reaction of 3,5-diphenylpyrazole
with Yb(C6F5)2, and the latter from protolysis of
[Sm{N(SiMe3)2}2(THF)2] with Ph2pzH, followed in each case
by crystallisation of the crude product from DME.
(DME), or Ph3PO; n ϭ 1Ϫ3) are monomeric with exclu-
sively η2-bonding.[6][7] Moreover, the preferred arrange-
ments of the three η2-pyrazolate ligands, can induce unex-
pected coordination modes of the co-ligands, e.g. bridging
DME ligands in [Nd(tBu2pz)3(DME)]ϱ, and novel unident-
ate DME in [Er(Ph2pz)3(DME)2].[7] Lanthanoid(II) pyrazo-
lates appear less favoured since the redox transmetallation/
ligand exchange reaction between Yb metal, Hg(C6F5)2,
and 3,5-di-tert-butylpyrazole yields [Yb(tBu2pz)3(THF)2]
even when an excess of the highly reducing metal is
used.[6a,6c] However, recently we have prepared the first lan-
thanoid(II) pyrazolate complex [Yb(Ph2pz)2(DME)2] by re-
dox transmetallation between Yb metal and thallium(I) 3,5-
diphenylpyrazolate, and also by redox transmetallation/li-
gand exchange between the lanthanoid element, HgPh2,
and 3,5-diphenylpyrazole.[8] Subsequently, use of 3,5-di-
tert-butylpyrazole in the latter synthetic method and crys-
tallisation of the product from petroleum ether gave
[Yb(tBu2pz)2(THF)]2, which contained the first example of
a µ-η2:η2-bonded pyrazolate.[3e] We now report a detailed
study of the synthesis and structures of a range of bis(1,2-
dimethoxyethane)bis(pyrazolato)lanthanoid(II) complexes,
as well as the preparation and structure of the closely re-
lated [Yb(azin)2(DME)2] (azinH ϭ 7-azaindole).
Introduction
Pyrazolate ligands have had an extensive role as bridging
ligands particularily between d-block metals, and as chelat-
ing ligands, particularily to f-block metals.[2] This chemistry
is now being enlivened by a range of new features, such as
the first homoleptic η2-pyrazolates,[3a] the first η2-d
block[3a,3b] and main-group[3c] pyrazolates, the use of pyra-
zolates in semiconductor doping,[3d] and new modes of pyr-
azolate coordination (µ-η2:η2[3e] and combined η2 and µ-
η1:η1[3f]). Recent investigations have provided synthetic
routes to a range of lanthanoid(III) pyrazolates.[4Ϫ7] Struc-
tures of initially prepared compounds revealed cages and
dimers with both bridging (µ-η1:η1) and chelating (η2) li-
gands.[4][5] However, lanthanoid(III) complexes of bulky
3,5-disubstituted pyrazolates [Ln(R2pz)3(L)n] (R ϭ tBu or
Ph; L ϭ tetrahydrofuran (THF), 1,2-dimethoxyethane
[a]
Chemistry Department, Monash University,
Clayton, Victoria 3168, Australia
Fax: (internat.) ϩ 61-3/9905-4597
E-mail: Glen.Deacon@sci.monash.edu.au
[b]
The Department of Chemistry, The University of Western
Australia,
Nedlands, Western Australia, 6907, Australia
Fax: (internat.) ϩ 61-8/9380-1005
Eur. J. Inorg. Chem. 1999, 751Ϫ761
WILEY-VCH Verlag GmbH, D-69451 Weinheim, 1999
1434Ϫ1948/99/0505Ϫ0751 $ 17.50ϩ.50/0
751

G. B. Deacon, E. E. Delbridge, B. W. Skelton, A. H. White
FULL PAPER
lation/ligand exchange from Yb metal, Hg(C6F5)2, and 3,5-
diphenylpyrazole. Because of the failure to prepare
Tl(tBu2pz), an alternative to Equation 4 was needed for
Eu(tBu2pz)2, and this was achieved by redox transmetall-
ation/ligand exchange between europium metal, di-
phenylmercury, and 3,5-di-tert-butylpyrazole (Equation 8),
Results and Discussion
Synthesis
A key step in the route to lanthanoid(II) pyrazolates was
the synthesis of the thallium(I) pyrazolates, Tl(bind) (1a)
(bindH ϭ 4,5-dihydro-2H-benz[g]indazole), Tl(MePhpz)
(1b) (MePhpzH ϭ 3-methyl-5-phenylpyrazole), Tl(azin)
(1c), Tl(Ph2pz)[8] (1d), and Tl(MePh2pz) (1e) (MePh2pzH ϭ
4-methyl-3,5-diphenylpyrazole).
Eu ϩ HgPh2 ϩ 2 tBu2pzH Ǟ Eu(tBu2pz)2 ϩ 2 PhH ϩ Hgȇ (8)
followed by isolation as [Eu(tBu2pz)2(DME)2] (4b). This
synthetic method has previously been used for
[Yb(Ph2pz)2(DME)2] (3d)[8] and [Yb(tBu2pz)2(THF)]2.[3e]
Since an attempt to prepare Sm(Ph2pz)2 by Equation 4
yielded instead Sm(Ph2pz)3 (Equation 9),[8]
Tl(OEt) ϩ R2RЈpzH Ǟ Tl(R2RЈpz) ϩ EtOH
(1)
However, Tl(tBu2pz) could not be prepared by this
method and appeared thermally unstable. Consistent with
pyrazolate formation, no ν(NH) absorption was observed
in the infrared spectra of the complexes, which were ad-
ditionally characterized by parent ions in their mass spectra
Sm ϩ 3 Tl(Ph2pz) Ǟ Sm(Ph2pz)3 ϩ 3 Tlȇ
(9)
two alternative approaches were used to give the divalent
target compound, viz metathesis (Equation 5) (Ln ϭ Sm),
and protolysis of bis[bis(trimethylsilyl)amido]samarium(II)
by 3,5-diphenylpyrazole.
1
and/or satisfactory H-NMR spectra. Another possible re-
dox transmetallation reagent, mercury(II) 3,5-diphenylpyr-
azolate (2a), was prepared both by metathesis (Equation 2),
HgCl2 ϩ 2 K(Ph2pz) Ǟ 2 KCl ϩ Hg(Ph2pz)2
(2)
Sm[N(SiMe3)2]2 ϩ 2 Ph2pzH Ǟ Sm(Ph2pz)2 ϩ 2 HN(SiMe3)2
(10)
and by mercuration of diphenylpyrazole under alkaline
conditions.
After workup with DME a much higher yield of
[Sm(Ph2pz)2(DME)2] (5) was obtained by the former
method.
HgBr42Ϫ ϩ 2 OHϪ ϩ 2 Ph2pzH Ǟ Hg(Ph2pz)2 ϩ 4 BrϪ ϩ 2 H2O (3)
Equation 4 opens the use of thallium-based redox trans-
metallation as a route to lanthanoid organoamides. Redox
transmetallation with thallium(I) reagents was a source of
only cyclopentadienyls[9] and phenolates,[10] prior to our
preliminary report.[8] Mercury-based redox transmet-
allation (e.g. Equation 6) has previously been used for lan-
thanoid amides,[9c,11] whilst use of diphenylmercury in re-
dox transmetallation/ligand exchange (e.g. Equation 8), is a
recent development[11] by contrast with the extensive use
of Hg(C6F5)2.[9aϪ9c]
The complex could not be obtained analytically pure, but
the identity was clear from an MHϩ ion in the electrospray
mass spectrum and the product was a viable source of
Yb(Ph2pz)2 (below).
Several thallium(I) pyrazolates and Tl(azin) were found
to undergo redox transmetallation with ytterbium and eu-
ropium in tetrahydrofuran to give the corresponding di-
valent pyrazolates.
The different outcomes of the reactions of ytterbium and
samarium with thallium 3,5-diphenylpyrazolate (Equation
Ln ϩ 2 Tl(R2pz) Ǟ Ln(R2pz)2 ϩ 2 Tlȇ
(4)
Crystallisation of the crude products from DME gave the 4; Ln ϭ Yb; R ϭ Ph and Equation 9) are explicable by the
complexes [Yb(bind)2(DME)2] (3a), [Yb(MePhpz)2- observation (Experimental Section) that samarium metal
(DME)2] (3b), [Yb(azin)2(DME)2] (3c), and [Eu(Ph2pz)2- does not reduce Sm(Ph2pz)3 whereas ytterbium metal re-
(DME)2] (4a). The reported [Yb(Ph2pz)2(DME)2], pre- duces Yb(Ph2pz)3.
viously prepared by Equation 4 and by redox transmetall-
2 Yb(Ph2pz)3 ϩ Yb Ǟ 3 Yb(Ph2pz)2
(11)
ation/ligand exchange from Yb metal, HgPh2, and
Ph2pzH,[8] was prepared in modest to good yields by three
further methods, viz. metathesis from ytterbium diiodide
(Equation 5, Ln ϭ Yb), redox transmetallation from im-
pure Hg(Ph2pz)2 (Equation 6), and protolysis of bis(pen-
tafluorophenyl)ytterbium(II) (Equation 7).
Formation of Yb(Ph2pz)2, rather than a trivalent com-
plex from redox transmetallation/ligand exchange between
ytterbium metal, diphenylmercury, and 3,5-diphenylpyr-
azole,[8] is guaranteed both by reduction (Equation 11), and
also by the current finding that Yb(Ph2pz)2 does not un-
dergo oxidation/ligand exchange with diphenylmercury
and Ph2pzH.
LnI2 ϩ 2 K(Ph2pz) Ǟ Ln(Ph2pz)2 ϩ 2 KI
Yb ϩ Hg(Ph2pz)2 Ǟ Yb(Ph2pz)2 ϩ Hgȇ
Yb(C6F5)2 ϩ 2 Ph2pzH Ǟ Yb(Ph2pz)2 ϩ 2 C6F5H
(5)
(6)
(7)
Ǟ
2 Yb(Ph2pz)2 ϩ HgPh2 ϩ 2 Ph2pzH ᎏ//
2 Yb(Ph2pz)3 ϩ 2 PhH ϩ Hg
Only, a short reaction time was needed for successful iso-
lation of Yb(Ph2pz)2 from Equation 7, otherwise a black
This further illuminates the contrasting formation of
[6a,6c]
unidentified solid was obtained, similar to the unsuccessful Yb(tBu2pz)3 from synthesis with Hg(C6F5)2
but Yb(t-
outcome of an attempted synthesis by redox transmetal- Bu2pz)2 with HgPh2.[3e] Synthetic consequences of the dif-
752
Eur. J. Inorg. Chem. 1999, 751Ϫ761

Organoamido- and Aryloxo-Lanthanoids, 19
FULL PAPER
fering oxidising capacity of these mercurials have been pre- eochemical types. Thus, the cenϪLnϪcen angles (cen ϭ
viously observed in that YbCp2 is converted by Hg(C6F5)2 centre of NϪN bonds or, for azin, the centre of the N···N
into YbCp2(C6F5), but is inert to diphenylmercury,[12a] and distance) (Table 3) are either in the range 101Ϫ108° (3a,
electrochemical reduction is more facile for Hg(C6F5)2 than 3d, 4b, 5; Figures 1Ϫ4) giving a cisoid disposition of the
for HgPh2.[12b,12c]
pyrazolate ligands, or 141Ϫ143° (3c, 4a; Figure 5, 6) giving
Despite the high air and moisture sensitivity of a transoid array of Ph2pz or azin ligands. A similar relation-
[Ln(R2pz)2(DME)2] complexes and [Yb(azin)2(DME)2], all ship is shown by the cenЈϪLnϪcenЈ angles (cenЈ ϭ mid-
complexes were obtained with acceptable C, H, N, and Ln point of the O···O distance) (Table 3), with 3a, 4b, 5, and
analyses. No ν(NH) absorptions were observed in the spec- 3d having values of 85Ϫ98° and a cisoid disposition of
tra, consistent with the formation of pyrazolatolanthanoid DME ligands. By contrast 3c and 4a have values of
1
complexes. The H-NMR spectra of the diamagnetic YbII 138Ϫ143° respectively, arising from transoid DME ligands,
complexes and of [Sm(Ph2pz)2(DME)2] were consistent where the four oxygen donor atoms are nearly coplanar.
with the proposed compositions, except for 3a where the All single crystals were obtained from concentrated DME
bind integrations were approximately half the expected solutions, hence the difference in arrangement seen in the
intensity, and where all resonances, especially those of bind, Ph2pz complexes 3d, 4a, and 5, and especially between the
were surprisingly broadened. This may be the source of the complexes of the adjacent metals Ln ϭ Eu or Sm, is strik-
low integrations. A spectrum of a cooled solution showed ing.
the same features. No YbIII impurities could be detected
by electronic spectroscopy (Experimental Section), and the
oxidation state is clear from spectroscopy, analysis and the
X-ray crystallography. Not only was the 1H-NMR spectrum
of the paramagnetic SmII complex 5 clearly resolved and
assigned (Experimental Section), but it was clearly dis-
tinguishable from that of the SmIII analogue,
[Sm(Ph2pz)3(DME)2].[8] The 171Yb resonance of the azin
complex 3c (Experimental Section) was very close to that
(δ ϭ 480) of [Yb(Ph2pz)2(DME)2],[8] consistent with our
view of the azin ligand as a pseudo-pyrazolate. It is also at
lower frequencies than the 171Yb chemical shift of seven-
coordinate [Yb(tBu2pz)2(THF)]2 (δ ϭ 536).[3e] There is
some evidence that a higher frequency shift accompanies a
decrease in coordination number in complexes with similar
ligands,[11][13] as in these examples, but 3c and 3d necessarily
were examined in DME and [Yb(tBu2pz)2(THF)]2 in PhMe.
The visible/near-IR spectra of the complexes show moder-
ately intense (for Ln complexes) features attributable to
LnǞL charge transfer (Experimental Section). More no-
tably near-infrared absorptions characteristic[14] of YbIII
and SmIII were absent from the spectra of the YbII and
SmII compounds.
X-ray Structure Determinations
Figure 1. Molecular projection of [Yb(bind)2(DME)2] (3a) down
the quasi-2 axis; no disorder is present
Single-crystal X-ray structure determinations have been
carried out for 3a, 3c, 4a, 4b, and 5. No complexes, includ-
Amongst the cis complexes, 4b, 5, and 3d differ from 3a
ing the analogous 3d of the preliminary report,[8] are iso- in that the Ln(R2pz)2 arrays have potential mm symmetry,
structural, and all show crystallographically independent one m bisecting the ligand and relating the two substituents.
forms. These are displayed in Figures 1Ϫ6, attention being By contrast, the Yb(bind)2 array in 3a is disposed as ap-
drawn to crystallographically significant features in the Fig- proaching 2 symmetry. In the transoid complexes, 3c and
ure captions and in the Experimental Section. Selected 4a, the Ph2pz and azin ligand pairs are closely coplanar
bond lengths and angles are in Tables 1 and 2. All with each other and with the metal atom. In the diphenyl-
[Ln(R2pz)2(DME)2] complexes have eight-coordinate pyrazolate complexes 4a, 5, and 3d, each pyrazolate ring is
monomeric structures with two chelating DME and two almost coplanar with its phenyl substituents, regardless of
chelating (η2)-pyrazolate or azin ligands. In each case the whether the Ph2pz groups are cisoid or transoid.
two nitrogen atoms bind nearly symmetrically to the metal
In 3a, one molecule devoid of crystallographic symmetry,
centre such that the metal is approximately coplanar with and of any complicating factors such as different bind li-
the ligand plane (Figures 1Ϫ6). There are two different ster- gand orientations (possible by reversal of the inequivalent
Eur. J. Inorg. Chem. 1999, 751Ϫ761
753

G. B. Deacon, E. E. Delbridge, B. W. Skelton, A. H. White
˚
FULL PAPER
Table 1. Metal atom environments in cisoid 5, 4b (molecules 1 and 2), 3d, 3a; connectivity to (r [A]) or via the metal centre (angles [°]);
* values are for the disordered/symmetry-related O component
Atom*
r
5 N(11Ј)
N(21)
N(21Ј)
N(122)
N(222)
N(22)
O(102)
O(1102)
O(2102)
O(102)
O(102)
O(105)
O(1105)
O(2105)
O(105)
O(105)
O(202)
O(1202)
O(2202)
O(202)
O(202)
O(205)
O(1205)
O(2205)
O(205)
O(205)
4b(1) N(112) N(121)
4b(2) N(212) N(221)
˚
[A]
3d N(12)
3a N(12)
N(21)
N(21)
N(22)
5 N(11)
2.556(3)
2.53(1)
31.07(8)
32.2(3)
31.6(3)
32.7(2)
32.6(1)
105.47(8)
112.8(3)
110.7(3)
107.3(2)
101.5(1)
97.10(8)
99.9(3)
98.3(3)
95.5(2)
112.7(1)
91.1(1)
92.3(3)
94.9(3)
87.7(2)
91.80(9)
76.0(1)
79.8(3)
78.7(3)
91.2(2)
76.91(9)
118.7(1)
123.4(3)
124.1(4)
116.7(2)
112.9(1)
155.24(9)
162.5(4)
166.0(3)
174.7(2)
156.7(1)
4b(1) N(111)
4b(2) N(211)
3d N(11)
2.51(1)
2.426(7)
2.465(3)
3a N(11)
5 N(11Ј)
(2.556(3))
2.527(9)
2.54(1)
2.414(7)
2.440(3)
(97.10(8))
103.5(3)
101.9(3)
96.4(2)
(105.47(8))
108.3(3)
107.4(3)
102.8(2)
117.2(1)
121.4(1)*
122.0(3)
123.3(3)
119.7(2)
123.5(1)
87.6(1)*
85.6(3)
83.8(3)
97.9(2)
85.2(1)
89.8(1)*
96.3(3)
97.5(4)
86.8(2)
83.7(1)
(155.24(9))
158.4(3)
158.8(3)
150.9(2)
147.1(1)
4b(1) N(112)
4b(2) N(212)
3d N(12)
3a N(12)
90.6(1)
5 N(21)
2.538(3)
2.54(1)
2.533(9)
2.430(7)
2.399(3)
30.99(1)
31.4(3)
32.3(3)
32.5(2)
33.1(1)
112.9(1)
118.7(3)
120.7(3)
116.8(2)
118.77(9)
173.0(1)
167.1(3)
169.6(3)
161.2(2)
174.3(1)
92.2(1)
96.7(3)
98.0(3)
91.0(2)
95.3(1)
97.1(1)
81.1(3)
79.5(3)
77.3(2)
101.8(1)
4b(1) N(121)
4b(2) N(221)
3d N(21)
3a N(21)
5 N(21Ј)
(2.538(3))
2.517(9)
2.511(9)
2.424(7)
2.459(3)
83.5(1)*
92.2(3)
93.8(3)
86.7(2)
86.7(1)
142.5(1)*
153.5(3)
154.0(3)
151.2(2)
152.6(1)
121.4(2)*
125.6(4)
127.2(4)
122.8(2)
115.8(1)
(97.1(1))
86.7(3)
85.3(3)
87.1(2)
87.1(1)
4b(1) N(122)
4b(2) N(222)
3d N(22)
3a N(22)
5 O(102)
2.720(7)
2.667(8)
2.693(8)
2.576(7)
2.519(3)
60.2(2)
61.4(3)
61.1(3)
65.6(2)
66.84(9)
134.8(2)
114.8(3)
110.4(3)
136.6(2)
133.26(9)
70.5(1)
71.2(4)
71.2(3)
87.9(2)
76.67(9)
4b(1) O(1102)
4b(2) O(2102)
3d O(102)
3a O(102)
5 O(105)
2.708(5)
2.724(9)
2.767(8)
2.484(6)
2.551(3)
93.0(2)
72.9(3)
72.4(3)
77.8(2)
80.5(1)
80.4(1)
87.1(3)
92.0(3)
84.4(2)
79.95(9)
4b(1) O(1105)
4b(2) O(2105)
3d O(105)
3a O(105)
5 O(202)
2.627(7)
2.69(1)
69.5(1)
62.2(4)
61.5(4)
65.2(2)
65.1(1)
4b(1) O(1202)
4b(2) O(2202)
3d O(202)
2.68(1)
2.502(6)
2.508(3)
3a O(202)
5 O(205)
2.551(4)
2.71(1)
4b(1) O(1205)
4b(2) O(2205)
3d O(205)
2.73(1)
2.558(7)
2.577(3)
3a O(205)
N donor atoms), comprises the asymmetric unit. However, highly symmetrical Ph2pz coordination, but different con-
in 3c, isomeric diversity arising from alternative azin orien- formations of the (non-disordered) DME ligands. Further,
tations is manifested as disorder, although one of the four no unusual asymmetry in the DME coordination is found
possible combinations is dominant, as is displayed in Fig- in complexes of the unsymmetrical ligands bind and azin.
ure 3a.
In 3a, the two DME ligands have different conformations
The pyrazolate and azin ligands are symmetrically coor- whilst in 3c they are the same. When appropriate allowance
˚
dinated with differences in LnϪN bond pairs Յ 0.06 A for is made for the differences in the ionic radii of eight coordi-
all ligands and Յ 0.03 A for all but two. Even the largest nate Eu2ϩ, Sm2ϩ, and Yb2ϩ[15], the <LnϪN> bond dis-
˚
differences, which, not surprisingly, are found for the un- tances of all complexes are very similar with sole exception
˚
symmetrical ligands bind and azin, are observed for only of 3c, where <YbϪN> is ca. 0.13 A longer than values for
one ligand in each of 3a and 3c, respectively. Moreover, the the other two YbII complexes, 3a and 3d. Given that the 7-
˚
maximum difference (0.06 A) is less than those (0.07Ϫ0.10 azindolate ligand is not a pyrazolate, it would be unwise at
III
A) in some Ln complexes with Ph2pz and tBu2pz.[6b,7a] this stage to attach too much significance to this difference,
˚
There is more asymmetry in the DME chelation with the but it can be argued that azin has more steric stress in the
˚
largest pair of differences (0.10, 0.06 A) in 3d which has immediate vicinity of the donor atoms than R2pz ligands
754
Eur. J. Inorg. Chem. 1999, 751Ϫ761

Organoamido- and Aryloxo-Lanthanoids, 19
FULL PAPER
Figure 2. Molecular projection of [Yb(Ph2pz)2(DME)2] (3d) down
the quasi-2 axis; no disorder is present
and the “bite” is also larger. Greater uniformity is seen in
ionic radius adjusted <LnϪO> values (despite greater indi-
vidual variation than for LnϪN), with a slight deviation in
˚
<EuϪO> of 4b, which is ca. 0.05 A longer than for other
complexes. This may be a consequence of the bulky tert-
butyl substituents of the tBu2pz ligand. For the azin com-
plex 3c, the YbϪO distances are similar to those of 3a and
3d, despite the longer YbϪN lengths. Comparison of bond
lengths in cisoid and transoid Ph2pz complexes 3d, 5, and
4a reveals no significant differences after allowance for
ionic radii differences. Subtraction of eight-coordinate Ln3ϩ
radii[15] from <LnϪN> values gives a residue of 1.28Ϫ1.32
˚
˚
A, for all complexes except for the anomalous 3c (1.42 A),
˚
and these are at the low end of the range, 1.26Ϫ1.38 A, for
[Ln(R2pz)3Ln] (L ϭ THF, n ϭ 2 or 3; L ϭ DME, n ϭ 1 or
2) complexes.[6,7a] The uniqueness of the azin coordination
is further illustrated by the subtraction value, which lies
outside the normal pyrazolatolanthanoid range. Similar
Figure 3. Molecular projections of [Sm(Ph2pz)2(DME)2] (5) (i)
down and (ii) normal to the quasi-2 axis; as modelled, the molecule
lies disposed to either side of a crystallographic mirror plane, pas-
sing through samarium and the mid-points of the NϪN bonds of
the pyrazolate ligands, i.e. normal to and vertical in the page in (i)
and in the plane of the page in (ii); the DME ligands are necessarily
disordered to either side of that plane, the two components having
different conformations, only one of each type being shown
˚
subtraction from <LnϪO> gives 1.38Ϫ1.40 A with the ex-
˚
ception of 1.45 A for the tBu2pz complex 4b. Values for
LnIII complexes [Ln(R2pz)3(THF)n] (n ϭ 2 or 3) cover the
[6]
˚
˚
range 1.35Ϫ1.38 A,
whilst [Er(Ph2pz)3(η2-DME)(η1-
kin Elmer 1600 FTIR spectrometer. Ϫ Mass spectra were obtained
with a VG Trio-1 GC mass spectrometer (Ln, Tl compounds) or a
1
˚
DME)] gives 1.35 A for the η -DME and 1.42 A for the
chelating DME.[7a] These subtraction residues suggest that Micromass Platform Electrospray mass spectrometer [Hg(Ph2pz)2].
Each listed m/z value for metal-containing ions (where the metal
has more than one isotope) is the most intense peak of a cluster
with an isotope pattern in good agreement with the calculated pat-
tern. Ϫ Room-temperature (20°C) NMR spectra were recorded
with a Bruker AC 200 MHz (1H, 13C) or AM 300 MHz (1H, 171Yb)
spectrometer. The chemical shift references were the residual sol-
the [Ln(R2pz)2(DME)2] structures are not greatly crowded,
especially given that analogous values for LnϪO(THF) in
crowded, bulky aryloxides lie in the range 1.49Ϫ1.59
[10b,10c,16]
˚
A.
vent signals ([D6]benzene: δH ϭ 7.15, δC ϭ 128.0; [D8]THF: δH
ϭ
Experimental Section
1.73, 3.58, δC ϭ 25.3, 67.4; [D8]toluene: δH ϭ 2.09) or external
[Yb(C5Me5)2(THF)2] (0.15  solution in THF) (171Yb: δ ϭ 0.0).[13]
Degrees of substitution for 13C nuclei were determined using 1H/
13C J-modulation pulse sequences. [D6]benzene (Cambridge Iso-
topes) was dried with sodium/potassium alloy and [D8]THF (Cam-
bridge Isotopes) was dried with CaH2. The deuterated solvents
General: The compounds described here are extremely air- and
moisture-sensitive and consequently all operations were carried out
in an inert atmosphere (purified argon or nitrogen). Unless indi-
cated otherwise, handling methods and solvent purification were as
described previously.[17] Petroleum ether refers to the fraction boil-
ing between 40 and 60°C. Ϫ IR data (4000Ϫ650 cmϪ1) were ob- were then vacuum-transferred to greaseless Schlenk tubes and
tained for Nujol mulls sandwiched between NaCl plates with a Per-
stored under purified argon. Ϫ Lanthanoid analyses were by
Eur. J. Inorg. Chem. 1999, 751Ϫ761
755

G. B. Deacon, E. E. Delbridge, B. W. Skelton, A. H. White
FULL PAPER
Figure 5. Molecular projection of [Yb(azin)2(DME)2] (3c) normal
to the the quasi-2 axis; minor disordered azin components beeing
shown
EDTA titration[18] with xylenol orange indicator of solutions pre-
pared by digestion of accurately weighed samples in concentrated
HNO3/2% concentrated H2SO4 followed by dilution with water and
buffering with hexamine. Thallium analyses were by potassium iod-
ate titration[19] of solutions prepared by digestion of accurately
weighed samples in concentrated HNO3/2% concentrated H2SO4.
Once the HNO3 was removed by heating, the residue was treated
with excess Na2SO3 to reduce Tl3ϩ to Tlϩ, and the solution was
boiled to expel excess SO2. Ϫ Microanalysis samples were sealed
in glass ampoules under purified argon and were determined either
by the Campbell Microanalytical Service, University of Otago, New
Figure 4. Molecular projection of [Eu(tBu2pz)2(DME)2] (4b) down
the quasi-2 axis (molecule 1 only is shown, molecule 2 being
pseudo-symmetrically related and therefore similar); one of the
DME ligands is disordered over two conformations, the two com-
ponents of the relevant atoms of the CH2CH2 group being shown
˚
Table 2. Metal atom environments in transoid 3c, 4a (molecules 1 and 2); connectivity to (r [A]) or via the metal centre (angles [°])
Atom
r
3c N(11)
N(27)
N(21)
N(112Ј)
N(212Ј)
O(102)
O(102)
O(202)
O(105)
O(105)
O(205)
O(202)
O(102Ј)
O(202Ј)
O(205)
O(105Ј)
O(205Ј)
˚
[A]
4a(1) N(112) N(111Ј)
4a(2) N(212) N(211Ј)
3c N(17)
4a(1) N(111)
4a(2) N(211)
2.569(6)
2.552(5)
2.554(6)
54.3(2)
31.0(2)
31.0(2)
87.6(2)
112.1(2)
111.7(2)
141.8(2)
141.4(2)
140.4(2)
83.4(2)
82.3(2)
80.9(2)
124.7(2)
123.1(2)
115.5(2)
80.3(2)
83.4(2)
84.2(2)
125.4(2)
107.6(2)
115.1(2)
3c N(11)
4a(1) N(112)
4a(2) N(212)
2.547(6)
2.582(4)
2.536(6)
141.7(2)
(141.4(2))
(140.4(2))
163.9(2)
172.2(2)
171.1(2)
98.4(2)
80.5(2)
96.3(2)
85.3(2)
96.1(2)
99.8(2)
86.5(2)
97.8(2)
81.6(2)
81.4(2)
89.8(2)
87.0(2)
3c N(27)
4a(1) N(111Ј)
4a(2) N(211Ј)
2.596(6)
54.4(2)
31.0(2)
31.0(2)
77.7(2)
83.4(2)
84.2(2)
124.7(2)
107.6(2)
115.1(2)
83.7(2)
82.3(2)
80.9(2)
126.3(2)
123.1(2)
115.5(2)
3c N(21)
4a(1) N(112Ј)
4a(2) N(212Ј)
2.538(6)
85.1(2)
(97.8(2))
(81.6(2))
82.0(2)
(89.8(2))
(87.0(2))
96.7(2)
(80.5(2))
(96.3(2))
85.6(2)
(96.1(2))
(99.8(2))
3c O(102)
4a(1) O(102)
4a(2) O(202)
2.523(5)
2.637(6)
2.614(5)
65.2(2)
63.5(2)
62.9(2)
155.7(2)
154.4(2)
153.2(2)
138.8(2)
141.6(2)
143.9(2)
3c O(105)
4a(1) O(105)
4a(2) O(205)
2.565(5)
2.660(5)
2.684(5)
139.0(1)
(141.6(2))
(143.9(2))
73.8(2)
80.9(2)
81.0(2)
3c O(202)
4a(1) O(102Ј)
4a(2) O(202Ј)
2.508(5)
65.3(1)
(63.5(2))
(62.9(2))
3c O(205)
2.553(5)
756
Eur. J. Inorg. Chem. 1999, 751Ϫ761

Organoamido- and Aryloxo-Lanthanoids, 19
FULL PAPER
lar amount of hydrazine hydrate in refluxing ethanol. These pyr-
azoles were then recrystallised from an acetone/petroleum ether
mixture. Lanthanoid(II) diiodides[22], bis[bis(trimethylsilyl)amido]bis-
(tetrahydrofuran)samarium(II),[23] bis(pentafluorophenyl)mercury-
(II),[24] and bis(pentafluorophenyl)ytterbium(II)[24] were syn-
thesised by the indicated reported method.
(4,5-Dihydro-2H-benz[g]indazolato)thallium(I) (1a): Thallium(I)
ethoxide (0.35 mL, 1.25 g, 5.0 mmol) was added to a diethyl ether
solution (30 mL) of 2H-benz[g]-4,5-dihydroindazole (0.85 g, 5.0
mmol) giving a white precipitate, which was filtered from solution
and washed twice with petroleum ether (2 ϫ 20 mL) yielding 1.62
g (87%) of a white crystalline solid. Ϫ IR: ν˜ ϭ 1608 cmϪ1 w, 1531
w, 1508 w, 1340 w, 1315 m, 1298 w, 1272 m, 1213 m, 1156 w, 1098
m, 1052 s, 1036 s, 1019 s, 1011 s, 960 s, 931 m, 887 m, 850 s, 762
1
vs, 732 s, 706 vs, 685 m, 659 w. Ϫ H NMR (200 MHz, [D8]THF):
δ ϭ 2.75 (t, 2 H, 4-H), 2.85 (t, 2 H, 5-H), 6.99Ϫ7.05 (m, 2 H, 6-H
and 9-H), 7.15 (t, 1 H, 7-H), 7.44 (s, 1 H, 3-H), 7.62 (t, 1 H, 8-H).
Ϫ
13C{1H} NMR (200 MHz, [D8]THF): δ ϭ 21.0 (C-4), 31.7 (C-
5), 118.0 (C-3a), 123.0 (C-9), 126.5 (C-8), 127.2 (C-7), 128.9 (C-3
and C-6), 132.5 (C-9a), 137.3 (C-5a), 151.7 (C-10a). Ϫ MS (70 eV,
EI); m/z (%): 374 (20) [(205Tl)Mϩ], 205 (85) [205Tlϩ], 170 (100)
[C11H10N2ϩ]. Ϫ C11H9N2Tl (373.6): calcd. Tl 54.71; found Tl
55.26.
Figure 6. Molecular projections of [Eu(Ph2pz)2(dme)2] (4a) (i)
down and (ii) normal to the quasi-2 axis [molecule 1; in molecule
2, the ligand disposition, inclusive of DME conformations (or-
dered), is similar; each molecule is disposed about a crystallo-
graphic 2 axis]; note the quasi parallel pairs of ligand planes, indi-
cative of dodecahedral stereochemistry about the metal centre
(3-Methyl-5-phenylpyrazolato)thallium(I) (1b): Thallium(I) ethoxide
Zealand or by Chemical and Microanalytical Services Pty. Ltd,
(0.35 mL, 1.25 g, 5.0 mmol) was added to a THF solution (30
Belmont, Australia. Ϫ Lanthanoid elements as either powders or mL) of 3-methyl-5-phenylpyrazole (0.79 g, 5.0 mmol) giving a pale
ˆ
distilled metal ingots were obtained from Rhone-Poulenc. Thal-
yellow solution. The THF was removed under vacuum giving 3
lium(I) ethoxide was purchased from Fluka or Merck and was fil-
as an off-white solid which was recrystallised from CH2Cl2 and
tered under argon to remove any thallium metal and stored at petroleum ether [1.40 g (77%)]. Ϫ IR: ν˜ ϭ 1599 cmϪ1 m, 1292 w,
Ϫ20°C in the dark. 7-Azaindole and HgPh2 were purchased from 1261 m, 1154 vw, 1092 m, 1070 m, 1019 s, 962 m, 866 vw, 791 w,
1
Aldrich. 4,5-Dihydro-2H-benz[g]indazole was synthesised by a re-
ported method[20]. Other pyrazoles were synthesised[21] by treating
the appropriate commercially available β-diketone with an equimo-
759 vs, 716 s, 696 vs. Ϫ H NMR (300 MHz, [D8]THF): δ ϭ 2.37
(s, 3 H, Me), 6.41 (s, 1 H, 4-H) 7.08Ϫ7.13 (m, 1 H, p-H), 7.17Ϫ7.23
(t, 2 H, m-H), 7.59 (d, 2 H, o-H). Ϫ MS (70 eV, EI); m/z (%): 362
Table 3. Diaza ligand centroid/other atom angles [°] (N1, N2 are the centroids of the pyrazolate ligands 1 and 2; O1 and O2 are the centres
of the O···O vectors of the DME ligands 1 and 2)
Compound/molecule
3c
transoid
4a/1
transoid
4a/2
transoid
3a
cisoid
3d
cisoid
4b/1
cisoid
4b/2
cisoid
5
cicoid
N1ϪLnϪN2
141.4
91.0
142.2
81.1
109.8
90.7
98.9
96.2
95.6
Ϫ
Ϫ
Ϫ
Ϫ
Ϫ
141.2
88.5
108.2
82.6
101.2
99.8
92.3
Ϫ
Ϫ
Ϫ
Ϫ
Ϫ
106.7
107.6
80.7
101.4
103.7
94.7
107.4
107.2
82.4
110.1
168.6
95.3
140.7
105.7
166.2
111.2
83.7
105.8
109.3
81.0
111.0
171.2
95.6
141.9
107.5
168.4
112.7
82.1
102.1
106.3
81.5
104.3
160.5
94.4
135.9
98.2
157.9
106.9
97.4
128.1
104.9
95.6
N1ϪLnϪO(102)
N1ϪLnϪO(105)
N1ϪLnϪO(202)
N1ϪLnϪO(205)
N1ϪLnϪO1
105.0
82.6
98.5
101.8
166.9
101.0
134.8
101.8
161.7
106.9
81.9
104.1
100.1
94.0
156.4
94.7
129.6
102.6
168.9
106.1
94.5
136.2
102.1
92.0
N2ϪLnϪO2
N2ϪLnϪO(102)
N2ϪLnϪO(105)
N2ϪLnϪO(202)
N2ϪLnϪO(205)
N2ϪLnϪO1
80.3
104.2
90.2
107.1
92.8
132.7
94.9
97.9
136.6
98.4
85.1
138.5
98.1
85.2
N2ϪLnϪO2
O1ϪLnϪO2
100.3
138.3
Ϫ
142.7
Ϫ
143.0
Eur. J. Inorg. Chem. 1999, 751Ϫ761
757

G. B. Deacon, E. E. Delbridge, B. W. Skelton, A. H. White
(40) [(205Tl)Mϩ], 205 (15) [205Tlϩ], 158 (15) [C10H10N2ϩ]. Ϫ ployed to separate the red solution from the deposited grey solids.
FULL PAPER
C10H9N2Tl (361.6): calcd. Tl 56.52; found Tl 56.84.
The THF was removed under vacuum yielding a red solid which
was dissolved in DME (40 mL) and allowed to stand for several
days at room temperature during which time 0.54 g (78%) of large
red crystals formed. Ϫ IR: ν˜ ϭ 1605 cmϪ1 m, 1528 w, 1509 w, 1297
w, 1275 w, 1240 w, 1224 w, 1210 w, 1191 w, 1121 m, 1097 s, 1073
s, 1045 w, 1028 w, 1009 m, 977 m, 954 m, 943 m, 884 m, 855 s, 818
s, 766 vs, 734 m, 716 vs, 686 m, 673 m. Ϫ 1H NMR (300 MHz,
[D8]THF): δ ϭ 2.73 and 2.79 (br. d, overlapping signals, total inte-
gration 4 H, 4-H,5-H), 3.31 (br. s, 12 H, MeO, DME), 3.48 (br. s,
8 H, CH2 DME), 7.00 (br. m, 3 H, 6-H,7-H,9-H), 7.55 (br. s, 1 H,
3-H), 7.85 (br. s, 1 H, 8-H). Integration of the indazolate protons
showed approximately half the expected intensity. Ϫ Visible/near
IR (THF): λmax (ε): 430 (415) nm. Ϫ C30H38N4O4Yb (691.7): calcd.
C 52.09, H 5.54, N 8.10, Yb 25.02; found C 51.91, H 5.66, N 7.27,
Yb 25.14.
(7-Azaindolato)thallium(I) (1c): Thallium(I) ethoxide (2.56 mL, 9.01
g, 36.1 mmol) was added to an ether solution (30 mL) of 7-azain-
dole (4.26 g, 36.1 mmol) giving a white precipitate and a pale yel-
low solution. The white precipitate was filtered from solution and
washed with petroleum ether (2 ϫ 30 mL) giving 1c [11.61 g (65%)].
Ϫ IR: ν˜ ϭ 1582 cmϪ1 w, 1534 w, 1333 w, 1278 m, 1257 w, 1150 m,
1
1092 m, 1044 w, 898 m, 798 s, 766 vs, 746 s, 721 vs, 622 m. Ϫ H
NMR (200 MHz, [D8]THF): δ ϭ 6.39 (s, 1 H, 3-H), 6.90 (dd, 1 H,
5-H) 7.30 (s, 1 H, 2-H), 7.87 (d, 1 H, 4-H), 8.05 (d, 1 H, 7-H). Ϫ
C7H5N2Tl (321.5): calcd. Tl 63.57; found Tl 64.11.
(3,5-Diphenylpyrazolato)thallium(I) (1d): The preparation and
properties have been given in a preliminary report.[8]
(4-Methyl-3,5-diphenylpyrazolato)thallium(I) (1e): Thallium(I)
ethoxide (0.35 mL, 1.25 g, 5.0 mmol) was added to a THF solution
(30 mL) of 4-methyl-3,5-diphenylpyrazole (1.17 g, 5.0 mmol) giving
a deep yellow solution. This was reduced in volume to ca. 5 mL
and petroleum ether was added causing deposition of 1e as a white
solid, which was filtered off and dried under vacuum [1.80 g (82%)].
Ϫ IR: ν˜ ϭ 1601 cmϪ1 m, 1528 w, 1516 w, 1292 w, 1248 w, 1225 w,
1145 w, 1117 s, 1070 s, 1011 s, 994 w, 966 w, 916 m, 847 w, 771 vs,
Bis(1,2-dimethoxyethane)bis(3-methyl-5-phenylpyrazolato)-
ytterbium(II) (3b): A mixture of ytterbium powder (1.73 g, 10.0
mmol), mercury metal (ca. 0.20 mL), and (3-methyl-5-phenylpyr-
azolato)thallium(I) (1.20 g, 2.31 mmol) in THF (30 mL) was sub-
jected to ultrasonication for 48 h. The resulting deep red solution
with grey suspended solids was allowed to stand for several hours
until the suspension settled out. The reaction mixture was then
filtered using a filter cannula. The filtrate was concentrated to dry-
ness under vacuum yielding a red solid which was dissolved in
DME which was subsequently removed under vacuum giving 3b
[0.48 g (62%)]. Ϫ IR: ν˜ ϭ 1602 cmϪ1 m, 1527 w, 1491 m, 1413 m,
1298 w, 1190 w, 1155 w, 1099 m, 1054 s, 1016 m, 964 m, 912 w, 888
m, 858 m, 762 vs, 712 m, 695 vs. Ϫ Visible/near IR (THF): λmax
1
718 s, 700 vs. Ϫ H NMR (300 MHz, [D8]THF): δ ϭ 2.26 (s, 3 H,
CH3), 7.20Ϫ7.26 (m, 2 H, p-H), 7.29Ϫ7.31 (m, 4 H, m-H), 7.44 (t,
4 H, o-H). Ϫ 13C{1H} NMR (400 MHz, [D8]THF): δ ϭ 12.2 (Me),
111.9 (C-4, pz), 127.2 (C-4, Ph), 129.1 (C-2,C-6 and C-3,C-5, Ph),
136.2 (C-1, Ph), 153.1 (C-3,C-5, pz). Ϫ MS (70 eV, EI); m/z (%):
438 (40) [(205Tl)Mϩ], 234 (90) [C16H14N2ϩ], 205 (15) [205Tlϩ], 130
(100) [C9H8Nϩ]. Ϫ C16H13N2Tl (437.7): calcd. C 43.90, H 2.99, N
6.40; found C 44.00, H 3.08, N 6.21.
1
(ε) ϭ 389 nm (586). Ϫ H NMR (300 MHz, [D8]THF): δ ϭ 2.22
(br. s, 6 H, 3-Me), 3.20 (s, 12 H, MeO DME), 3.36 (s, 8 H, CH2
DME), 6.30 (br. s, 2 H, 4-H), 6.96 (br. s, 2 H, p-H), 7.14 (br. s, 4
H, m-H), 7.72 (br. s, 4 H, o-H). Ϫ C28H38N4O4Yb (667.7): calcd.
Yb 25.92; found Yb 25.82.
Bis(3,5-diphenylpyrazolato)mercury(II) (2)
Method A: 3,5-Diphenylpyrazole (1.00 g, 4.5 mmol) was treated
with a THF solution (30 mL) of potassium hydride (0.18 g, 4.5
mmol) at 0°C. Gas evolution was observed and a slightly pale yel-
low solution formed. HgCl2 (0.62 g, 2.3 mmol) was added causing
formation of a white precipitate. The reaction mixture was stirred
for 1 h and then was treated with water. The precipitated mercurial
2 was filtered off, washed with water, ethanol, and ether, and then
dried under vacuum for 30 min giving 1.10 g (76%) of impure 2 as
a white powder. Ϫ IR: ν˜ ϭ 1604 cmϪ1 m, 1542 w, 1400 m, 1236 w,
1321 w, 1296 w, 1274 m, 1236 m, 1157 m, 1128 m, 1074 s, 1026 m,
1001 w, 986 m, 958 w, 914 m, 844 w, 800 w, 758 vs, 696 vs. Ϫ MS
(electrospray); m/z (%): 641 (100) [(202Hg)MHϩ], 549 (100)
Bis(7-azaindolato)bis(1,2-dimethoxyethane)ytterbium(II) (3c):
A
mixture of ytterbium powder (1.73 g, 10.0 mmol), mercury metal
(ca. 0.20 mL), and (7-azaindolato)thallium(I) (0.64 g, 2.0 mmol) in
THF (30 mL) was subjected to ultrasonication for 16 h. The re-
sulting deep red solution with grey suspended solids was allowed
to stand for several hours until the suspension settled out. The
reaction mixture was then filtered using a filter cannula. The filtrate
was concentrated to dryness under vacuum yielding a red solid
which was recrystallised from DME giving 3c [0.41 g (70%)]. Ϫ IR:
ν˜ ϭ 1581 cmϪ1 m, 1542 m, 1402 w, 1335 w, 1321 m, 1295 s, 1258
m, 1193 m, 1153 s, 1118 m, 1060 m, 1020 m, 984 m, 951 w, 907 w,
896 w, 857 vs, 795 s, 771 s, 744 s, 718 vs, 617 m, 598 m. Ϫ Visible/
[
202HgC23H15N4ϩ], 467 (76) [202HgC17H19N3ϩ]. Ϫ C30H22N4Hg
(639.1): calcd. C 56.38, H 3.47, N 8.77; found C 54.57, H 3.77,
N, 8.07.
1
near IR (THF): λmax (ε) ϭ 480 nm (259). Ϫ H NMR (300 MHz,
[D6]benzene): δ ϭ 2.79 (s, 12 H, MeO DME), 2.83 (s, 8 H, CH2
DME), 6.74 (m, 4 H, 2-H,5-H), 7.88 (s, 2 H, 2-H), 7.97 (m, 4 H,
4-H,7-H). Ϫ 171Yb NMR (52.5 MHz, 0.04  in DME): δ ϭ 489
(∆ν1/2 ϭ 54 Hz). Ϫ C22H30N4O4Yb (587.6): calcd. C 44.97, H 5.15,
N 9.54, Yb 29.45; found C 43.85, H 4.82, N 10.01, Yb 29.41.
Method B: HgBr2 (1.80 g, 5.0 mmol) and NaBr (2.05 g, 20 mmol)
were dissolved in tBuOH (80 mL). 3,5-Diphenylpyrazole (2.20 g,
10 mmol) and NaOH (0.80 g, 20 mmol) were added and the reac-
tion mixture was refluxed for 4 h. The cream-coloured solution was
poured into distilled H2O (150 mL) giving bis(3,5-diphenylpyrazol-
ato)mercury as a cream precipitate which was filtered from the
solution and dried under vacuum. The infrared spectrum of this
compound was in good agreement with that of the product from
Method A and a yield of > 90% was obtained.
Bis(1,2-dimethoxyethane)bis(3,5-diphenylpyrazolato)ytterbium(II)
(3d)
Method A: A mixture of ytterbium powder (0.83 g, 4.8 mmol) and
Hg(Ph2pz)2 (1.00 g, 2.4 mmol) in THF (30 mL) was subjected to
ultrasonication for 6 d. The resulting deep red solution with grey
suspended solids was allowed to stand for several hours, and was
Bis(2H-benz[g]-4,5-dihydroindazolato)bis(1,2-dimethoxyethane)-
ytterbium(II) (3a): A mixture of ytterbium powder (0.69 g, 4.0
mmol) and (2H-benz[g]-4,5-dihydroindazolato)thallium(I) (0.74 g, then filtered. The THF was removed under vacuum giving a deep
2.0 mmol) in THF (30 mL) was subjected to ultrasonication for 24
h. The resulting deep red solution with grey suspended solids was
allowed to stand for several hours, when a filter cannula was em-
red sticky solid which was recrystallised from DME affording 1.10
g (58%) of large red crystals. Ϫ IR: identical with that reported.[8]
Ϫ C38H42N4O4Yb (791.8): calcd. Yb 21.85; found Yb 22.28, 22.04.
758
Eur. J. Inorg. Chem. 1999, 751Ϫ761

Organoamido- and Aryloxo-Lanthanoids, 19
FULL PAPER
Method B: Yb(C6F5)2, generated in situ from ytterbium metal (1.73
Method B: SmI2(THF)2 (0.54 g, 1.0 mmol) was added to a THF
g, 10.0 mmol) and Hg(C6F5)2 (1.07 g, 2.0 mmol) was treated with
solution (30 mL) of (3,5-diphenylpyrazolato)potassium(I) (2.0
3,5-diphenylpyrazole (0.88 g, 4.0 mmol) in THF (30 mL). After mmol) (generated in situ as described above in the synthesis of 3d)
stirring at room temerature for 15 min, the THF was removed and causing formation of a dark purple solution and a white precipitate.
the red solid was recrystallised from DME [0.34 g, (22%)]. Ϫ IR This reaction mixture was stirred for 12 h followed by removal of
and visible/near IR (THF): identical with those reported.[8]
THF to give a sticky purple solid, which was extracted with toluene
(30 mL) giving a red/brown solution and a white precipitate. The
toluene solution was filtered and concentrated to dryness yielding
dark purple 5 which was recrystallised from DME [0.48 g (62%)].
Ϫ IR: identical with that of the product from Method A. Ϫ
C38H42N4O4Sm (769.2): calcd. Sm 19.55; found Sm 19.90.
Method C: 3,5-Diphenylpyrazole (0.59 g, 2.7 mmol) was treated
with a THF solution (30 mL) of potassium hydride (0.11 g, 2.7
mmol) at 0oC. To the resulting solution YbI2(THF)2 (0.77 g, 1.35
mmol) was added causing an formation of a red solution and a
white precipitate. After stirring for 12 h, removal of THF gave a
sticky orange solid which was extracted with in toluene (80 mL)
giving a red/brown solution and a white precipitate. After filtration,
the toluene solution was concentrated to dryness giving a red solid
which was recrystallised from DME [0.40 g (37%)]. Ϫ IR: identical
with that reported.[8] Ϫ C38H42N4O4Yb (791.8): calcd. Yb 21.85;
found Yb 21.52.
Reaction between 3d and HgPh2 and Ph2pzH: 3d (0.40 g, 0.50
mmol), HgPh2 (0.89 g, 0.25 mmol) and Ph2pzH (0.55 g, 0.25 mmol)
were stirred in DME (30 mL) at room temperature for 2 d. The
reaction mixture remained red and there were no signs of precipi-
tated metal. A visible/near-IR spectrum of the reaction mixture was
indentical to that reported[8] for 3d.
Reaction between (1,2-Dimethoxyethane)tris(3,5-diphenylpyrazola-
to)ytterbium(III) and Ytterbium Metal: A mixture of (1,2-dimeth-
oxyethane)tris(3,5-diphenylpyrazolato)ytterbium(III)[25] (0.46 g,
0.50 mmol), ytterbium metal (1.73 g, 10.0 mmol), and mercury
metal (ca. 0.20 mL) in DME (30 mL) were subjected to ultra-
sonication for 24 h. The initially colourless solution turned deep
red after sonication for 12 h. Separation of excess ytterbium and
mercury followed by removal of DME yielded a red solid. Visible/
near-IR and IR spectra were indentical with those reported[8] for
3d.
Bis(1,2-dimethoxyethane)bis(3,5-diphenylpyrazolato)europium(II)
(4a): A mixture of europium metal chunks (0.61 g, 4.0 mmol), mer-
cury metal (ca. 0.20 mL) and (3,5-diphenylpyrazolato)thallium(I)
(0.85 g, 2.0 mmol) in THF (30 mL) was subjected to ultra-
sonication for 48 h. The resulting deep yellow solution with grey
suspended solids was allowed to stand for several hours. Filtration,
and evaporation of the THF yielded a yellow solid, which was
recrystallised from DME giving 0.69 g (90%) of 4a as large yellow
crystals. Ϫ IR: ν˜ ϭ 1602 cmϪ1 m, 1157 w, 1120 w, 1193 w, 1115 m,
1096 m, 1069 s, 1057 s, 1025 m, 1016 m, 980 m, 968 s, 907 w, 852
s, 832 w, 794 w, 770 m, 750 vs, 697 s, 682 s. Ϫ C38H42EuN4O4
(770.7): calcd. C 59.22, H 5.49, Eu 19.72, N 7.27; found C 59.06,
H 5.67, Eu 19.68, N 7.59.
Reaction between Bis(1,2-dimethoxyethane)tris(3,5-diphenylpyrazol-
ato)samarium(III) and Samarium Metal: A mixture of bis(1,2-dime-
thoxyethane)tris(3,5-diphenylpyrazolato)samarium(III)[8] (0.99 g,
1.0 mmol), samarium metal (1.50 g, 10.0 mmol), and mercury me-
tal (ca. 0.20 mL) in DME (30 mL) were subjected to ultra-
sonication for 2 d. The initially colourless solution remained
colourless after sonication for 2d. A visible/near IR spectrum of
the reaction mixture was indentical with that reported[8] for
[Sm(Ph2pz)3(DME)2].
Bis(3,5-di-tert-butylpyrazolato)bis(1,2-dimethoxyethane)eur-
opium(II) (4b): A mixture of europium metal chunks (1.52 g, 10.0
mmol), mercury metal (ca. 0.20 mL), diphenylmercury(II) (0.98 g,
2.78 mmol) and 3,5-di-tert-butylpyrazole (1.00 g, 5.56 mmol) in
THF (30 mL) was heated (60°C) for 24 h. The resulting deep yellow
solution with grey suspended solids was allowed to stand for sev-
eral hours. Filtration, and evaporation of the THF yielded a yellow
solid, which was recrystallised from DME giving 0.57 g (59%) of
4b as large yellow crystals. Ϫ IR: ν˜ ϭ 1509 cmϪ1 m, 1404 w, 1354
m, 1318 w, 1248 s, 1218 m, 1195 m, 1158 w, 1123 m, 1103 m, 1078
s, 1032 m, 1010 s, 996 m, 860 vs, 769 vs, 722 vs. Ϫ Visible/near IR
(THF): λmax (ε) ϭ 345 nm (477). Ϫ C38H42EuN4O4 (690.8): calcd.
C 52.16, H 8.46, Eu 22.00, N 8.11; found C 51.28, H 8.39, Eu
22.02, N 8.88.
Attempted Reaction of Ytterbium Metal with Hg(C6F5)2 and 3,5-
Diphenylpyrazole: A mixture of ytterbium powder (1.73 g, 10.0
mmol), mercury metal (ca. 0.20 mL), bis(pentafluorophenyl)mercu-
ry(II) (0.53 g, 1.0 mmol), and 3,5-diphenylpyrazole (0.44 g, 2.0
mmol) in THF (40 mL) was stirred at room temperature for 4 d.
On addition of THF an orange solution formed. This progressively
darkened to a black solution over the course of the reaction. The
resulting black solution with grey suspended solids was allowed to
stand for several hours. Filtration and removal of THF under vac-
uum revealed a black solid which was insoluble in DME. The infra-
red spectrum of this black material was significantly different from
that obtained for compound 3d. Ϫ IR: ν˜ ϭ 1365 cmϪ1 m, 1303 w,
1246 m, 1193 m, 1112 br. s, 1028 m, 983 m, 940 m, 852 s, 763 vw,
723 vw.
Bis(1,2-dimethoxyethane)bis(3,5-diphenylpyrazolato)samarium(II)
(5)
Method A: 3,5-Diphenylpyrazole (0.27 g, 1.2 mmol) was treated
with
a
THF solution (30 mL) of bis[bis(trimethylsilyl)-
amido]bis(tetrahydrofuran)samarium(II) (0.38 g, 0.60 mmol). The
resulting purple solution was stirred for 30 min, and the THF was
then removed under vacuum yielding a purple solid which was
washed twice with petroleum ether (2 ϫ 30 mL). The purple solid
was recrystallised from DME (30 mL) giving 0.12 g (25%) of 5 as
Structure Determinations: Room-temperature single-counter/four-
circle diffractometer data sets were measured on capillary-mounted
specimens (2θ/θ-scan mode; graphite-monochromated radiation, λ ϭ
˚
0.71073 A; T ഠ 295 K), in most cases with symmetry equivalences,
dark purple crystals. Ϫ IR: ν˜ ϭ 1602 cmϪ1 m, 1509 w, 1243 w, yielding Ntotal reflections, these being merged (Rint as specified) after
1220 w, 1156 w, 1121 w, 1101 m, 1073 s, 1026 m, 1014 w, 967 s,
absorption correction, yielding N (unique) data, No with I > 2σ(I)
913 w, 860 m, 849 m, 793 w, 758 vs, 697 s, 685 s. Ϫ Visible/near IR
being considered “observed” and used in the full-matrix least-
(THF) λmax (ε): ca. 600 br. (900) nm. Ϫ 1H NMR (300 MHz, squares refinement (nv variables). Anisotropic thermal parameters
[D8]THF): δ ϭ Ϫ11.76 (s, 2 H, H-4), 2.93 (d, 8 H, o-H), 3.48 (s, were refined for the non-hydrogen atoms, (x, y, z, Uiso)H being in-
12 H, MeO, DME), 3.54 (s, 8 H, CH2, DME), 5.84 (t, 4 H, p-H), cluded constrained at estimated values. Conventional residuals R, Rw
6.73 (t, 8 H, m-H). Ϫ C38H42N4O4Sm (769.2): calcd. C 59.34, H [statistical weights, derivative of σ2(I) ϭ σ2(Idiff) ϩ 0.0004 σ4(Idiff)]
5.50, N 7.28, Sm 19.55; found C 59.42, H 5.63, N 7.51, Sm 19.26.
on ԽFԽ are quoted at convergence. Neutral atom complex scattering
Eur. J. Inorg. Chem. 1999, 751Ϫ761
759

G. B. Deacon, E. E. Delbridge, B. W. Skelton, A. H. White
factors were employed, the Xtal 3.4 program system[26] being used. cmϪ1; specimen: 0.25 ϫ 0.35 ϫ 0.55 mm; A*min,max ϭ 1.47, 1.72
FULL PAPER
Individual abnormalities, variations in procedure and idiosyncrasies
are noted as “variata”; in no case was there difference-map evidence
for occluded solvent, although ligand disorder was evident in some
cases (see below). In Figures 1Ϫ6, 20% thermal ellipsoids are shown
for the non-hydrogen atoms, hydrogen atoms having arbitrary radii
(gaussian correction). 2θmax ϭ 60°; Ntotal ϭ 8395, N ϭ 3650 (Rint ϭ
0.029), No ϭ 2240; R ϭ 0.042, Rw ϭ 0.037; nv ϭ 270. Խ∆ρmaxԽ ϭ
Ϫ3
˚
1.04 e A
.
Variata: As modelled in the present space group, the DME moieties
are disordered across the crystallographic mirror plane; meaningful
refinement could not be achieved in a lower symmetry space group.
An ordered component is shown in the Figures and Tables and has
a crystallographic mirror plane passing through the metal atom
and relating the two halves (including substituents) of each Ph2pz
ligand. Despite similar Ln sizes, the M ϭ Eu, Sm adducts 4a, 5 are
not isomorphous with each other, or with the Yb adduct 3d.
˚
of 0.1 A. In the case of 5 and 4a pairs of molecular projections
(Figures 3 and 6) are shown and provide views (i) down the actual
or putative 2 axis of the molecule, so as to display that symmetry,
and (ii) normal to that axis. The latter is provided to display better
(a) any difference in conformation among the pair of DME ligands,
(b) any ligand disorder, (c) any tendency to dodecahedral coordi-
nation about the metal atom [the (N2)2 ligand pair comprising one
of the two intersecting planes and the (O2)2 the other]. Crystallo-
graphic data (excluding structure factors and including torsion
angles describing the DME conformations) for the structures re-
ported in this paper have been deposited with the Cambridge Crys-
tallographic Data Centre as supplementary publication nos. CCDC-
101118 (3d)[8] and -109937Ϫ109941. Copies of the data can be
obtained free of charge on application to CCDC, 12 Union Road,
Cambridge CB2 1EZ, UK [Fax: int. code ϩ 44-1223/336-033;
E-mail: deposit@ccdc.cam.ac.uk].
4b [Eu(tBu2pz)2(DME)2]: C30H58EuN4O4, M ϭ 690.8. Triclinic,
1
¯
space group P1 (Ci , no. 2), a ϭ 22.791(4), b ϭ 15.709(4), c ϭ
˚
10.289(3) A, α ϭ 89.38(2), β ϭ 82.31(2), γ ϭ 84.49(2)°, V ϭ 3634
A . Dcalcd. (Z ϭ 4) ϭ 1.263 g cmϪ3; F(000) ϭ 1444. µMo ϭ 17.6
3
˚
cmϪ1; specimen: 0.40 ϫ 0.50 ϫ 0.50 mm; A*min,max ϭ 1.60, 2.12
(gaussian correction). 2θmax ϭ 50°; Ntotal ϭ 19495, N ϭ 12765
(Rint ϭ 0.047), No [I > 3σ(I)] ϭ 6027; R ϭ 0.057, Rw ϭ 0.064; nv ϭ
Ϫ3
˚
700. Խ∆ρmaxԽ ϭ 1.45 e A
.
Variata: One of the DME groups is conformationally disordered in
each molecule, discrete (CH2)2 carbon atoms being resolvable and
refined (C thermal parameters isotropic) with site occupancies set
at 0.5 after trial refinement. Crystal decomposition of 55% was
evident during data collection (isotropic) and compensated by sca-
ling.
Crystal/Refinement Data
3a [Yb(bind)2(DME)2]: C30H38N4O4Yb, M ϭ 691.7. Monoclinic,
space group P21/c (C2h5, no. 14), a ϭ 15.570(2), b ϭ 23.434(5), c ϭ
3
˚
˚
8.052(3) A, β ϭ 94.98(2)°, V ϭ 2927 A . Dcalcd. (Z ϭ 4) ϭ 1.570 g
cmϪ3; F(000) ϭ 1392. µMo ϭ 32.4 cmϪ1; specimen: 0.45 ϫ 0.30 ϫ
0.45 mm; A*min,max ϭ 2.28, 3.85 (analytical correction). 2θmax
ϭ
55°; N ϭ 6476, No [I > 3σ(I)] ϭ 4954; R ϭ 0.026, Rw ϭ 0.029; nv ϭ
Ϫ3
˚
Acknowledgments
333. Խ∆ρmaxԽ ϭ 1.13 e A
.
We are grateful to the Australian Research Council for financial
support and for the award of an Australian Postgraduate Award to
E. E. D.
3c [Yb(azin)2(DME)2]: C22H30N4O4Yb, M ϭ 587.6. Orthorhombic,
space group Pbca (D2h15, no. 61), a ϭ 18.183(4), b ϭ 16.567(6),
3
c ϭ 15.855(9) A, V ϭ 4776 A . Dcalcd. (Z ϭ 8) ϭ 1.634 g cmϪ3
;
˚
˚
F(000) ϭ 2336. µMo ϭ 39.5 cmϪ1; specimen: 0.12 ϫ 0.40 ϫ 0.45
mm; A*min,max ϭ 1.60, 4.2 (analytical correction). 2θmax ϭ 55°;
Ntotal ϭ 11095, N ϭ 5483 (Rint ϭ 0.028), No ϭ 3229; R ϭ 0.034,
[1]
G. B. Deacon, C. M. Forsyth, P. C. Junk, B. W. Skelton, A. H.
Ϫ3
˚
White, J. Chem. Soc., Dalton Trans. 1998, 1381Ϫ1388.
Rw ϭ 0.038; nv ϭ 299. Խ∆ρmaxԽ ϭ 0.80 e A
.
[2]
[2a] S. Trofimenko, Chem. Rev. 1972, 72, 497Ϫ509. Ϫ [2b] S. Trof-
imenko, Prog. Inorg. Chem. 1986, 34, 115Ϫ210. Ϫ [2c] A. P. Sadi-
menko, S. S. Bassoon, Coord. Chem. Rev. 1996, 147, 247Ϫ297.
Variata: Each azin ligand is capable of coordinating in two modes
involving interchange of nitrogen atoms with various associated
possibilities of isomerism; these modes are both observed for each
ligand, C(4,4Ј) [Figure 5: C(14), C(14Ј) and C(24), C(24Ј) of the
respective ligands] of each being the only constituent atoms suffi-
ciently displaced from overlap to permit meaningful refinement of
the alternate fragments. Site occupancies (x, 1 Ϫ x) for the two
ligands refined to x ϭ 0.83, 0.77(3), isotropic thermal parameter
forms being used for the minor fragments.
Ϫ
[2d] G. La Monica, G. A. Ardizzoia, Prog. Inorg. Chem. 1997,
[2e]
46, 151Ϫ238. Ϫ
1998, 110, 298Ϫ299; Angew. Chem. Int. Ed. Engl. 1998, 37,
286Ϫ287.
J. E. Cosgriff, G. B. Deacon, Angew. Chem.
[3] [3a]
I. A. Guzei, A. G. Baboul, G. P. A. Yap, A. L. Rheingold,
H. B. Schlegel, C. H. Winter, J. Am. Chem. Soc. 1997, 119,
[3b]
2287Ϫ2288. Ϫ
I. A. Guzei, G. P. A. Yap, C. H. Winter,
Inorg.Chem. 1997, 36, 1738Ϫ1739. Ϫ [3c] D. Pfeiffer, M. J. Heeg,
C. H. Winter, Angew. Chem. 1998, 110, 2674Ϫ2676; Angew.
[3d]
Chem. Int. Ed. Engl. 1998, 37, 2517Ϫ2519. Ϫ
T. D. Culp, J.
[M(Ph2pz)2(DME)2] (M ؍ Yb, Eu, Sm): C38H42MN4O4.
G. Cederberg, B. Bieg, T. F. Keuch, K. L. Bray, D. Pfeiffer, C.
[3e]
H. Winter, J. Appl. Phys. 1998, 83, 4918Ϫ4927. Ϫ
G. B.
[3d (M ؍ Yb) has been recorded elsewhere;[8] a redeposition has
been made, with atoms relabelled as shown in Figure 2, in conform-
ity with present arrays, which conform to the quasi-2 symmetry of
the system.]
Deacon, E. E. Delbridge, B. W. Skelton, A. H. White, Angew.
Chem. 1998, 110, 2372Ϫ2373; Angew. Chem. Int. Ed. Engl.
1998, 37, 2251Ϫ2252. Ϫ [3f] C. Yelamos, M. J. Heeg, C. H. Win-
´
ter, Inorg. Chem. 1998, 37, 3892Ϫ3894.
[4]
H. Schumann, P. R. Lee, J. Loebel, Angew. Chem. 1989, 101,
1073Ϫ1074; Angew. Chem. Int. Ed. Engl. 1989, 28, 1033Ϫ1035.
4a (M ؍ Eu): M ϭ 770.7. Monoclinic, space group P2/c (C2h4, no.
[5] [5a]
H. Schumann, J. Loebel, J. Pickardt, C. Qian, Z. Xie, Or-
˚
13), a ϭ 19.746(3), b ϭ 12.635(2), c ϭ 15.396(2) A, β ϭ 110.12(1),
[5b]
ganometallics 1991, 10, 215Ϫ219. Ϫ
G. B. Deacon, B. M.
3
V ϭ 3607 A . Dcalcd. (Z ϭ 4) ϭ 1.419 g cmϪ3; F(000) ϭ 1572.
˚
Gatehouse, S. Nickel, S. N. Platts, Aust. J. Chem. 1991, 44,
613Ϫ621.
µMo ϭ 17.8 cmϪ1; specimen: 0.55 ϫ 0.30 ϫ 0.30 mm; A*min,max
ϭ
[6]
[6a] J. E. Cosgriff, G. B. Deacon, B. M. Gatehouse, H. Hemling,
1.50, 1.82 (gaussian correction). 2θmax ϭ 50°; N ϭ 6328, No
ϭ
H. Schumann, Angew. Chem. 1993, 105, 906Ϫ907; Angew.
Ϫ3
˚
4823; R ϭ 0.046, Rw ϭ 0.049; nv ϭ 427. Խ∆ρmaxԽ ϭ 0.85 e A
.
[6b]
Chem. Int. Ed. Engl. 1993, 32, 874Ϫ875. Ϫ
J. E. Cosgriff,
G. B. Deacon, B. M. Gatehouse, Aust. J. Chem. 1993, 46,
16
5 (M ؍ Sm): M ϭ 769.1. Orthorhombic, space group Pnma (D2h
,
[6c]
1881Ϫ1896. Ϫ
J. E. Cosgriff, G. B. Deacon, B. M. Gate-
˚
no. 62), a ϭ 7.9941(6), b ϭ 24.263(3), c ϭ 19.080(3) A, V ϭ 3701
house, H. Hemling, H. Schumann, Aust. J. Chem. 1994, 47,
1223Ϫ1235.
A . Dcalcd. (Z ϭ 4) ϭ 1.380 g cmϪ3; F(000) ϭ 1568. µMo ϭ 16.3
3
˚
760
Eur. J. Inorg. Chem. 1999, 751Ϫ761

Organoamido- and Aryloxo-Lanthanoids, 19
FULL PAPER
[7]
[7a] J. E. Cosgriff, G. B. Deacon, G. D. Fallon, B. M. Gatehouse,
Chemistry of Rare Earths (Eds.: K. A. Gschneidner, L. Eyring),
North-Holland, Amsterdam, 1979, vol. 3, chapter 24.
R. D. Shannon, Acta Crystallogr., Sect. A 1976, 32, 751Ϫ767.
G. B. Deacon, T. Feng, B. W. Skelton, A. H. White, Aust. J.
Chem. 1995, 48, 741Ϫ756.
G. B. Deacon, C. M. Forsyth, B. M. Gatehouse, A. Philosof,
B. W. Skelton, A. H. White, P. A. White, Aust. J. Chem. 1997,
50, 959Ϫ970.
J. L. Atwood, W. E. Hunter, A. L. Wayda, W. J. Evans, Inorg.
Chem. 1981, 20, 4115Ϫ4119.
H. Schumann, R. Weimann, Chem. Ber. 1996, 129, 953Ϫ958.
Ϫ [7b] J. E. Cosgriff, G. B. Deacon, B. M. Gatehouse, P. R. Lee,
H. Schumann, Z. Anorg. Allg. Chem. 1996, 622, 1399Ϫ1403.
G. B. Deacon, E. E. Delbridge, B. W. Skelton, A. H. White,
Eur. J. Inorg. Chem. 1998, 543Ϫ545.
[15]
[16]
[8]
[17]
[9] [9a]
H. Schumann, J. A. Meese-Marktscheffel, L. Esser, Chem.
[9b]
Rev. 1995, 95, 865Ϫ986. Ϫ
F. T. Edelmann, in Comprehen-
[18]
[19]
sive Organometallic Chemistry, 2nd ed. (Eds.: G. Wilkinson, F.
G. A. Stone, E. W. Abel), Pergamon, Oxford, 1995, chapter 2.
G. H. Jeffery, J. Basset, J. Mendham, R. C. Denney, VogelЈs
Textbook of Quantitative Chemical Analysis, 5th ed., Longman
Scientific & Technical, New York, 1989, p. 404.
A. L. Rheingold, R. L. Ostrander, B. S. Haggerty, S. Trofi-
menko, Inorg. Chem. 1994, 33, 3666Ϫ3676.
[9c]
Ϫ
M. N. Bochkarev, L. N. Zakharov, G. S. Kalinina, Orga-
noderivatives of Rare Earth Elements, Kluwer Academic Press,
Dordrecht, 1995. Ϫ [9d] G. B. Deacon, G. N. Pain, T. D. Tuong,
[20]
[9e]
Inorg. Synth. 1990, 28, 291Ϫ297. Ϫ
G. B. Deacon, A. J.
Koplick, G. N. Pain, T. D. Tuong, in Herrmann-Brauer, Syn-
thetic Methods of Organometallic and Inorganic Chemistry, 3rd
ed. (Ed. W. A. Herrmann), G. Thieme, Stuttgart, 1997, vol. 6,
pp. 54Ϫ55, 86Ϫ87.
[21] [21a] B. Sjollema, Justus Liebigs Ann. Chem. 1894, 279, 248Ϫ257.
[21b]
Ϫ
M. S. R. Murthy, E. V. Rao, Indian Drugs 1985, 22,
462Ϫ464 (Chem. Abstr. 1986, 105, 6443e).
[22] [22a]
P. L. Watson, T. H. Tulip, I. Williams, Organometallics
1990, 9, 1999Ϫ2009. Ϫ [22b] J. L. Namy, P. Girard, H. B. Kagan,
P. E. Caro, in Herrmann-Brauer, Synthetic Methods of Or-
ganometallic and Inorganic Chemistry, 3rd ed., (Ed.: W. A.
Herrmann), G. Thieme, Stuttgart, 1997, vol. 6, pp. 26Ϫ27.
[10] [10a]
G. B. Deacon, P. B. Hitchcock, S. A. Holmes, M. F. Lap-
pert, P. MacKinnon, R. H. Newnham, J. Chem. Soc., Chem.
Comm. 1989, 935Ϫ937. Ϫ [10b] G. B. Deacon, T. Feng, S. Nickel,
M. I. Ogden, A. H. White, Aust. J. Chem. 1992, 45, 671Ϫ683.
[10c] G. B. Deacon, T. Feng, P. MacKinnon, R. H. Newnham,
[23] [23a]
Ϫ
W. J. Evans, D. K. Drummond, H. Zhang, J. L. Atwood,
[23b]
S. Nickel, B. W. Skelton, A. H. White, Aust. J. Chem. 1993,
46, 387Ϫ399.
Inorg. Chem. 1988, 27, 575Ϫ579. Ϫ
W. J. Evans, D. K.
Drummond, H. Zhang, J. L. Atwood, in Herrmann-Brauer,
Synthetic Methods of Organometallic and Inorganic Chemistry,
3rd ed. (Ed.: W. A. Herrmann), G. Thieme, Stuttgart, 1997, vol.
6, pp. 28Ϫ29.
[11]
G. B. Deacon, G. D. Fallon, C. M. Forsyth, H. Schumann, R.
Weimann, Chem. Ber. 1997, 130, 409Ϫ415.
[12] [12a]
G. B. Deacon, D. L. Wilkinson, Inorg. Chim. Acta. 1988,
[24]
G. B. Deacon, J. E. Cosgriff, E. T. Lawrenz, C. M. Forsyth, D.
L. Wilkinson, in Herrmann-Brauer, Synthetic Methods of Or-
ganometallic and Inorganic Chemistry, 3rd ed. (Ed.: W. A.
Herrmann), G. Thieme, Stuttgart, 1997, vol. 6, pp. 48Ϫ50.
G. B. Deacon, E. E. Delbridge, B. W. Skelton, A. H. White,
unpublished results.
142, 155Ϫ159. Ϫ [12b] K. P. Butin, A. N. Kashin, I. P. Beleskaya,
L. S. German, V. R. Polishchuk, J. Organomet. Chem. 1970, 25,
11Ϫ16. Ϫ [12c] K. P. Butin, I. P. Beleskaya, A. N. Kashin, O. A.
Reutov, J. Organomet. Chem. 1967, 10, 197Ϫ210.
[25]
[26]
[13] [13a]
J. R. van den Hende, P. B. Hitchcock, S. A. Holmes, M. F.
[13b]
Lappert, J. Chem. Soc., Dalton Trans. 1995, 1435Ϫ1440. Ϫ
S. R. Hall, H. D. Flack, J. M. Stewart (Eds.), The XTAL 3.2
Reference Manual, Universities of Western Australia, Geneva
and Maryland, 1992.
A. G. Avent, M. A. Edelman, M. F. Lappert, G. A. Lawless, J.
Am. Chem. Soc. 1989, 111, 3423Ϫ3425.
[14]
W. T. Carnell, in The Absorption and Fluorescence Spectra of
Rare Earth Ions in Solution in Handbook on the Physics and
Received November 17, 1998
[I98398]
Eur. J. Inorg. Chem. 1999, 751Ϫ761
761