β-diketiminate gallium amides: Useful synthons in gallium chemistry

Article abstract of DOI:10.1002/ejic.200900540

The facile preparation of ss-diketiminate gallium amides with general formulas of either LGa(NHR)₂ (L = [HC(C(Me)N(Ar)J₂]-, Ar = 2,6-iPr₂C₆H₃; R = Et (1), iPr (2), nBu (3), Ph (4)} or LGa(NHR)Cl [R = tBu (5); Bt (6)] was accomplished by the reaction of LGaCl₂ with the lithium salt of the corresponding amine in 1:2 (1-4) or 1:1 (5, 6) molar ratios. Compounds 1-6 are useful synthons for further synthesis, as the amide substituents are excellent leaving groups, and the resulting amines can be cleanly and easily removed from the reaction matrix. To demonstrate this, compounds 1 and 5 were treated with ethanol, leading to the alcoholysis products LGa(OEt)₂ (8) and LGa(OEt)Cl (9), respectively. Furthermore, LGa(OH)₂ can be obtained in an almost quantitative yield from the hydrolysis of compounds 1-4. Additionally, the aluminum analogue of 1 - LAl(NHEt)₂ (7) - was obtained to prove that the method is also suitable for other metals. Compounds 1-9 were characterized by common spectroscopic methods, and compounds 1-8 were also characterized by X-ray singlecrystal diffraction Wiley-VCH Verlag GmbH & Co. KGaA.

Full text of DOI:10.1002/ejic.200900540

FULL PAPER
DOI: 10.1002/ejic.200900540
β-Diketiminate Gallium Amides: Useful Synthons in Gallium Chemistry
Diego Solis-Ibarra,[a] A. Paulina Gómora-Figueroa,[a] Nieves Zavala-Segovia,[a] and
Vojtech Jancik*[a]
Keywords: Gallium / Amides / O ligands / Aluminum
The facile preparation of β-diketiminate gallium amides with
general formulas of either LGa(NHR)2 {L = [HC{C(Me)N-
(Ar)}2]–, Ar = 2,6-iPr2C6H3; R = Et (1), iPr (2), nBu (3), Ph (4)}
or LGa(NHR)Cl [R = tBu (5); Et (6)] was accomplished by the
reaction of LGaCl2 with the lithium salt of the corresponding
amine in 1:2 (1–4) or 1:1 (5, 6) molar ratios. Compounds 1–6
are useful synthons for further synthesis, as the amide sub-
stituents are excellent leaving groups, and the resulting
amines can be cleanly and easily removed from the reaction
matrix. To demonstrate this, compounds 1 and 5 were treated
with ethanol, leading to the alcoholysis products LGa(OEt)2
(8) and LGa(OEt)Cl (9), respectively. Furthermore, LGa(OH)2
can be obtained in an almost quantitative yield from the
hydrolysis of compounds 1–4. Additionally, the aluminum an-
alogue of 1 Ϫ LAl(NHEt)2 (7) Ϫ was obtained to prove that
the method is also suitable for other metals. Compounds 1–9
were characterized by common spectroscopic methods, and
compounds 1–8 were also characterized by X-ray single-
crystal diffraction.
(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim,
Germany, 2009)
Introduction
prepare compounds of general formula LGa(NHR)2 start-
[11]
ing from the easily accessible LGaCl2
and lithium salts
Recently, we reported on the preparation of molecular
aluminophosphite LAl(SH)(µ-O)P(OEt)2 and aluminosili-
cates LAl(EH)(µ-O)Si(OH)(OtBu)2, (E = O, S; L = [HC{C-
(Me)N(2,6-iPr2C6H3)}2]–) and LAl(Z)(µ-O)Si(OtBu)3, (Z =
H, OH, SH) and their use for the preparation of heterobi-
metallic systems.[1–3] Thus, we became interested in whether
or not it was possible to obtain similar systems based on
of primary amines. Primary amines were chosen because of
the large steric demand of the β-diketiminate ligand. The
LGa(NHR)2 compounds should have reactivity similar to
LGa(NH2)2, which is known to react cleanly with water to
form LGa(OH)2,[8] but their synthesis and purification
should be easier, as it was reported that LGa(NH2)2 always
contains inseparable impurities after the synthesis.[8] There-
fore, these gallium amides could serve as interesting precur-
sors in gallium chemistry, which are currently missing. Al-
though there are previous reports of gallium diamides, they
are mainly oligomeric compounds and the stabilization of
monomeric molecules requires the use of bulky arylamides,
and thus, their reactivity is limited.[12–17] To the best of our
knowledge, only few structurally characterized gallium
amides containing at least one terminal alkylamino group
have been reported so far. Thus, two terminal tert-bu-
tylamino groups were observed in [{tBu(H)N}2Ga{µ-N(H)
tBu}]2.[18] and one terminal N(H)SiMe3 group was reported
in Cl2Ga(THF)N(H)SiMe3.[19] Herein we want to report on
the preparation of four gallium diamide compounds of ge-
neral formula LGa(NHR)2 and LAl(NHEt)2, two com-
pounds of general formula LGa(NHR)Cl, and the
alcoholysis products LGa(OEt)2 and LGa(OEt)Cl.
[4]
gallium. However, whereas LAlH2 and LAl(SH)2,[5] used
as the starting materials for the aluminophosphite and alu-
minosilicates, are easily accessible precursors, there are very
few suitable equivalents available in gallium chemistry. Such
suitable gallium compounds should be sufficiently stable
but reactive enough to easily undergo, for example, control-
lable hydrolysis to offer easy access to a functional group
such as OH attached to the gallium atom. From this point
of view, only Ga–N bonds fulfil these requirements on sta-
bility and reactivity, because the hydrolysis of a Ga–Me
moiety is rather difficult and LGaMe(OH) has been re-
ported to melt without decomposition at 200 °C.[6] To date,
only few such compounds have been reported, and in all
cases, their preparation is tedious and/or requires expensive
reagents such as Arduengo’s imidazoyl carbene[7] [in the
case of LGa(NH2)2][8] or compounds containing the gal-
lium atom in an oxidation state of +I.[9,10] Our aim was to
[a] Centro de Investigación en Química Sustentable UAEM-
UNAM,
Results and Discussion
Car. Toluca-Atlacomulco km 14.5, Unidad San Cayetano, Per-
sonal del Instituto de Química, UNAM
Toluca 50200, Estado de México, México
Fax: +52-55-56-16-22-17
We tried three different methods to prepare these com-
pounds, namely, transamination between LGa(NH2)2 and a
primary amine (Method 1), direct amination of LGaCl2 in
E-mail: vjancik@servidor.unam.mx
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β-Diketiminate Gallium Amides: Useful Synthons in Gallium Chemistry
the presence of Arduengo’s imidazoyl carbene as HCl scav-
enger (Method 2), and reaction between LGaCl2 and the
lithium salt of the corresponding primary amine
(Method 3, Scheme 1). Although all three methods have
shown to be feasible for the preparation of the target com-
pounds, we selected Method 3 because of the rather labori-
ous preparation of LGa(NH2)2 and its difficult purification.
Also, the preparation of Arduengo’s carbene necessary for
Methods 1 and 2 is rather tedious if absolutely anhydrous
carbene should be obtained (synthesis of the imidazolium
salt, liberation of the corresponding carbene, and its purifi-
cation either by sublimation or recrystallization).[20] This is
necessary, as any trace amounts of water in the reaction
Scheme 2. Synthesis of compounds 1–7.
lead directly to the formation of LGa(OH)2. As reported
elsewhere, lithium salts of primary amines are highly reac- 1–8 were confirmed by X-ray single-crystal diffraction. The
1
tive and unstable if not stabilized by a base such as formation of compounds 1–7 was evidenced by H NMR
N,N,NЈ,NЈ-tetramethylethylenediamine.[18–20] Only the spectroscopy in C6D6, which revealed the presence of the
hexameric salt (tBuNHLi)6 has been reported to be stable signals corresponding to the N–H protons at δ = –0.27 (for
without any coordinating base.[18] Therefore, the in situ 1), –0.13 (for 2), –0.16 (for 3), 6.16 (for 4), –0.03 (for 5),
preparation of a known amount of the amine salt was ac- –0.02 (for 6), and –0.29 ppm (for 7). The signal appears at
complished by slow addition of an excess amount of the low field only in the case of compound 4, which is probably
corresponding amine to a solution of a known amount of caused by partial delocalization of the lone electron pair at
MeLi or nBuLi in THF at –78 °C. The resulting suspension the nitrogen atom into the π electron system of the aromatic
was warmed to ambient temperature and after stirring for ring. This is supported by the planar environment of the
30 min added dropwise to a solution of LGaCl2 at –78 °C. N3 and N4 atoms in 4. The corresponding signal of the N–
The products were isolated as white or slightly yellowish H proton in compounds 1–3 and 7 appears at lower field
microcrystalline solids in acceptable yields (up to 86%). In than the signal for the N–H protons in LAl(NH2)2 (δ =
the case of ethylamine, isopropylamine, n-butylamine, or –0.52 ppm)[21] and LGa(NH2)2 (δ = –0.58 ppm), but at
aniline, the product was the disubstituted derivative higher field compared to those in 5 and 6. The latter is
LGa(NHR)2 (1, R = Et; 2, R = iPr; 3, R = nBu; 4, R = Ph) caused by the presence of the chlorine atom attached to
but in the case of tert-butylamine, only the monosubstituted the same metallic center as the amino group. In case of
derivative LGa(NHtBu)Cl (5) was obtained independently compounds 1–3, 6, and 7, coupling of the N–H protons
on the ratio of the reactants or the reaction conditions; this with the α hydrogen atoms of the alkyl chain was observed.
is obviously due to the steric effects of the bulky ligand The presence of the NH moiety was further confirmed by
L and the tBu group. However, LGa(NHEt)Cl (6) can be IR spectroscopy. In compounds 1–4 and 7, the correspond-
obtained if the lithium salt of ethylamine reacts with ing vibrations were found in a narrow interval ν = 3371–
˜
LGaCl2 in a 1:1 molar ratio. To prove that this method can 3381 cm–1, which is in a good agreement with the νs vi-
be also used for different metals, we prepared the aluminum bration of the NH group in LAl(NH ) (ν = 3396 cm–1)[21]
˜
2
2 2
analogue of compound 1: LAl(NHEt)2 (7; Scheme 2).
and LGa(NH ) (ν = 3373 cm–1).[8] In cases of compounds
˜
2 2
5 and 6, the matching vibrations were found at lower wave-
numbers [ν = 3338 (for 5), 3335 cm–1 (for 6)]. These facts
˜
suggest that the electronic effects of the alkyl or aryl substit-
uents have only little effect on the wavenumber; however,
the presence of only one amino group in the molecule leads
to a lower wavenumber when the second substituent is chlo-
rine. The molecular peaks [M]+ for all compounds except 3
were observed by MS (EI), albeit at low intensity [m/z (%)
= 574 (3), 1; 602 (2), 2; 670 (6), 4; 593 (9), 5; 565 (6), 6; 532
(2), 7]. The base peak belongs to [M – NHR]+ in all cases,
except 6 [m/z (%) = 530, 1; 544, 2; 558, 3; 578, 4; 521, 5;
488, 7]. In the case of 6, the base peak at m/z = 506 corre-
sponds to [M – NHEt – Me]+. The easy fragmentation of
the Ga–Nexo bond confirms our expectations of its high
reactivity. In the next step, the obtained gallium amides
were treated with protic reagents. The reaction of 1 and 5
Scheme 1. Methods 1–3 used for the preparation of compounds 1–
4.
All compounds are white or slightly yellowish crystalline with ethanol led to LGa(OEt)2 (8) and LGa(OEt)Cl (9),
powders and were characterized by common physical meth- respectively, in nearly quantitative yields Ϫ the products
ods, and the molecular and crystal structures of compounds were isolated in 95% yield (Scheme 3).
Eur. J. Inorg. Chem. 2009, 4564–4571
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D. Solis-Ibarra, A. P. Gómora-Figueroa, N. Zavala-Segovia, V. Jancik
FULL PAPER
1
In both cases, the H NMR and IR spectra are essen-
tially devoid of the corresponding signals for the N–H pro-
tons. However, characteristic peaks of the ethoxy moieties
1
can be observed in the H NMR spectra of compounds 8
and 9, respectively. It is noteworthy that compound 8 is the
first gallium compound containing two terminal ethoxy
groups. Up to now, only [{(Me3Si)3Si}(EtO)Ga(µ-OEt)]2,[22]
[(tBuO)HGa(µ-OtBu)]2,[23] Ga(OtBu)3NHMe2,[24] Ga[(µ-
OiPr)2Ga(OiPr)2]3,[24] Ga[OCH(CF3)2]3(4-Me2Npy) (py =
pyridine),[25] Ga[OCMe2CF3]3(4-Me2Npy),[25] and [Ga(µ-
[24]
OCMe2Et)(OCMe2Et)2]2
have been reported to contain
at least one terminal alkoxide group. The only other com-
pounds containing nonbridging Ga–O(alkyl) bonds are sta-
bilized against oligomerization by the presence of donor
groups that fill vacant coordination sites of the gallium
atom and can lead to an increase in the coordination
number for gallium to 5 or 6. Some examples of such com-
plexes are Me2GaO(CH2)nNH2 (n = 2 or 3),[26,27] EtGa-
Scheme 3. Synthesis of compounds 8, 9, and LGa(OH)2.
Figure 1. Crystal structures of compounds 1–8. All carbon-bound hydrogen atoms are omitted for clarity. Thermal ellipsoids are drawn
at 50% probability.
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Eur. J. Inorg. Chem. 2009, 4564–4571

β-Diketiminate Gallium Amides: Useful Synthons in Gallium Chemistry
Table 1. Selected bond lengths [Å] and angles [°] for compounds 1–8.
1[a]
2[a]
3[a]
4[a]
5[a,b]
6[a]
8[a]
7[a]
M1–N1
1.997(1)
1.964(2)
1.862(2)
1.843(2)
94.5(1)
106.5(1)
116.3(1)
111.7(1
111.5(1)
114.4(1)
1.979(2)
1.978(2)
1.857(2)
1.837(2)
94.2(1)
111.9(1
114.3(1)
113.3(1)
109.4(1)
112.5(1)
1.968(2)
1.976(2)
1.846(2)
1.855(3)
95.2(1)
111.9(1)
112.9(1)
114.5(1)
106.0(1)
114.7(1)
1.945(3)
1.947(3)
1.862(3)
1.851(3)
96.4(1)
110.4(1)
115.0(1)
116.4(1)
109.0(1)
109.3(1)
1.939(2)
1.939(2)
1.850(3)
2.200(1)
97.5(1)
116.9(3)
105.6(1)
108.9(4)
105.6(1)
119.6(1)
1.916(3)
1.947(3)
1.825(4)
2.213(1)
97.5(1)
114.5(2)
108.9(1)
117.9(2)
103.6(1)
113.0(1)
1.949(1)
1.935(1)
1.812(1)
1.802(1)
97.3(1)
110.9(1)
114.4(1)
114.2(1)
111.1(1)
108.7(1)
1.928(2)
1.908(2)
1.794(2)
1.787(2)
95.2(1)
108.0(1)
115.3(1)
112.0(1)
113.0(1)
112.4(1)
M1–N2[b]
M1–X1[a]
M1–X2[a]
N1–M1–N2[a,b]
N1–M1–X1[a,b]
N1–M1–X2[a,b]
N2–M1–X1[a,b]
N2–M1–X2[a,b]
X1–M1–X2[a,b]
[a] For compounds 1–6 and 8, M = Ga; for compound 7, M = Al. For compounds 1–4 and 7, X1 = N3; X2 = N4; for compound 5, X1
= N2; X2 = Cl1; for compound 6, X1 = N3; X2 = Cl1; for compound 8, X1 = O1; X2 = O2. [b] In compound 5, only half of the
molecule is in the asymmetric unit; thus, N2 = N1A.
(OCH2CH2NMe2)2,[28] ClGa[OC(CF3)2CH2NMe2]2,[29] and of these bonds.[31,32] This shortening of the Ga–Nexo bond
ClGa[OC(CF3)2CH2CMe=NMe]2.[29] Moreover, the syn- is even larger in compound 6 [1.825(1) Å] owing to the pres-
thesis of dialkoxygallium derivatives usually requires high ence of the electronegative chlorine atom attached to the
temperatures, redistribution, or substitution (synthesis from gallium center and a small substituent on the nitrogen
trialkoxides by replacing one of the alkoxy groups by other atom. A similar effect can also be observed in compound
substituent, mostly halogen atom) reactions. Therefore, 8, where the Ga–O bonds [1.812(1) and 1.802(1) Å] are ne-
compounds 1–6 are interesting precursors for the synthesis arly 0.1 Å shorter than the sum of the covalent radii of
of gallium alkoxides, which are important synthons for gal- gallium and oxygen (1.90 Å).[30] Nevertheless, they are
lium oxide materials. Furthermore, previously reported slightly longer or comparable to the terminal Ga–O(alkyl)
LGa(OH)2[8] can be obtained from the controlled hydrolysis bonds in [{(Me3Si)3Si}(EtO)Ga(µ-OEt)]2 [1.785(7) Å],[22]
of compounds 1–4 in an almost quantitative yield (up to [(tBuO)HGa(µ-OtBu)]2 [1.782(5) Å],[23] Ga(OtBu)3NHMe2
95% isolated product). This is a significant improvement in [1.799(2)–1.822(2) Å],[24] Ga[(µ-OiPr)2Ga(OiPr)2]3 (av.
the synthesis of this compound, as the procedure does not 1.805 Å, only bonds without disorder),[24] Ga[OCH(CF3)2]3-
need any expensive reagents and is easily scalable.
(4-Me2Npy) (py = pyridine) [1.801(5)–1.811(5) Å],[25] Ga-
The solid-state structures of compounds 1–8 were deter- [OCMe2CF3]3(4-Me2Npy) [1.778(9)–1.802(8) Å],[25] [Ga(µ-
mined by X-ray crystallography (Figure 1). The isomorph- OCMe2Et)(OCMe2Et)2]2 [1.768(2)–1.782(2) Å],[24] and
ous compounds 1 and 7 and compound 8 crystallize in the LGa(OH)2 [1.777(1)–1.820(1) Å],[8] but shorter than those
monoclinic space group P21/n with one molecule in the in (iPrO)Ga(S2CNEt2)2 [1.932(1) Å][33] and in LGa(µ-O)2-
asymmetric unit. Of the remaining compounds, the follow- GaL [1.848(1) and 1.854(1) Å].[9] Furthermore, the Ga–Cl
ing also crystallize in the monoclinic system (the corre- bond lengths found for 5 [2.200(1) Å] and 6 [2.213(1) Å]
sponding space group and asymmetric unit content are are comparable to those in the starting material LGaCl2
given in the parenthesis): compound 2 (P21, one molecule), [2.218(1), 2.228(1) Å].[11] In all nine compounds, the coordi-
compound 3 (P21/c, one molecule), compound 5 (P21/m, nation sphere around the central metal has a distorted tet-
half of the molecule), and compound 6 (P21/c, one mole- rahedral geometry, where the Nendo–M–Nendo (1–6, 8 M =
cule). Finally, compound 4 crystallizes in the orthorhombic Ga; 7 M = Al) angle is the most acute one with a relatively
space group Pcca with one molecule of 4 and one half of a narrow range of values [94.2(1)–97.5(1)°]. The other angles
toluene molecule in the asymmetric unit. Compounds 1–8 around the metal center display significantly higher varia-
are discrete molecules in the solid state with no apparent tions, as the interval is 16° wide with the range 103.6(1)–
hydrogen bonding. The general feature of compounds 1–4 119.6(1)°. Selected bond lengths and angles for compounds
is the coordination of the central gallium atom to four 1–8 are reported in Table 1.
atoms of nitrogen Ϫ two from the β-diketiminate ligand
(endo) and two from the amine substituents (exo). There is
Conclusions
a clear difference in the bond lengths for the Ga–Nexo [in
Seven group 13 monomeric diamides (1–7) were synthe-
1: 1.862(2), 1.843(2) Å; 2: 1.857(2), 1.837(2) Å; 3: 1.846(2),
sized, and their reactivity towards protonolysis was proven
1.855(2) Å; and 4: 1.862(2), 1.851(2) Å] and Ga–Nendo [1:
through the isolation of LGa(OEt)2, LGa(OEt)Cl, and the
1.977(1), 1.964(2) Å; 2: 1.979(2), 1.978(2) Å; 3: 1.968(2),
previously reported LGa(OH)2 in nearly quantitative yields.
1.976(2) Å; and 4: 1.945(2), 1.947(2) Å] bonds, confirming
The possibilities to use these gallium amido compounds for
the partial donor–acceptor character of the latter bonds,
the preparation of more complex systems are underway.
which are similar to those observed in LGa(NH2)2
[1.852(2), 1.847(2), 1.955(2), and 1.976(2) Å]. The values for
Experimental Section
General: All manipulations described bellow were performed under
the Ga–Nexo bonds are in general smaller than the sum of
the covalent radii for gallium and nitrogen (1.90 Å),[30]
which is probably a result of the higher ionic contribution a dry nitrogen atmosphere using Schlenk and glove box techniques.
Eur. J. Inorg. Chem. 2009, 4564–4571
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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D. Solis-Ibarra, A. P. Gómora-Figueroa, N. Zavala-Segovia, V. Jancik
FULL PAPER
The solvents were purchased from Aldrich and dried prior to use.
Aniline, isopropylamine, n-butylamine, and tert-butylamine (Ald-
rich, 99%) were dried (CaH2) and purified by distillation under a
[HN(CH2)3CH3], 20.6 [HN(CH2)2CH2CH3], 23.4 (CH3), 24.7, 25.5
[CH(CH3)2], 28.1 [CH(CH3)2], 38.9 (NHCH2CH2CH2CH3), 46.5
(NHCH2nPr), 96.1 (γ-CH), 124.3, 126.9 (m-, p-C of Ar), 142.0 (i-
protective nitrogen atmosphere. LGaCl2, LAlCl2, and LiNHtBu C of Ar), 144.3 (o-C of Ar), 169.2 (C=N) ppm. MS (EI): m/z (%)
were prepared according to literature procedures.[11,18] Ethylamine
(2.0  in THF), methyllithium (3.0  in dimethoxyethane), and n-
butyllithium (2.0  in hexane) solutions were purchased from Ald-
rich and used as received. C6D6 was distilled from Na/K alloy and
degassed (3ϫ) before use. NMR spectroscopic data were recorded
with Jeol Eclipse or Bruker Avance 300 MHz spectrometers and
referenced to the residual protons of the deuterated solvent. Ele-
mental analyses were performed with an Exeter Analytical CE-440
analyzer. We were not able to obtain elemental analyses of satisfac-
tory quality for compounds 1 and 7 because of their high reactivity.
= 558 (100) [M – NHnBu]+.
LGa(NHPh)2 (4): nBuLi (2.0 , 1.9 mL, 3.8 mmol) was added
dropwise to a solution of NH2Ph (0.35 mL, 3.8 mmol) in THF
(15 mL) at –78 °C. The reaction mixture was warmed to ambient
temperature, stirred for an additional 30 min, and then slowly
added to LGaCl2 (1.00 g, 1.79 mmol) in THF (15 mL) at –78 °C.
The reaction mixture was warmed to ambient temperature and
stirred for an additional 6 h. All the volatiles were removed in
vacuo. The product was extracted with toluene and rinsed with
hexane. Compound 4 was obtained as a pale-yellow microcrystal-
line solid. Yield: 0.89 g (74%). M.p. 218–220 °C. C41H53GaN4
(671.6): calcd. C 73.32, H 7.95, N 8.34; found C 72.9, H 7.8, N 8.0.
LGa(NHX)2 [X = Et (1), iPr (2), nBu (3)]: The corresponding amine
(1: 2.0  in THF, 5.00 mL, 10.0 mmol; 2: 1.00 mL, 11.6 mmol; 3:
1.00 mL, 10.2 mmol) was added dropwise to a solution of MeLi
(3.0 , 1.25 mL, 3.75 mmol) in THF (15 mL) at –78 °C. The reac-
tion mixture was warmed to ambient temperature, stirred for an
additional 30 min, and then slowly added to a solution of LGaCl2
(1.00 g, 1.79 mmol) in THF (15 mL) at –78 °C. The reaction mix-
ture was warmed to ambient temperature and stirred for an ad-
ditional 2 h. All the volatiles were removed in vacuo, and the prod-
ucts were extracted with hexane. Compounds 1–3 were obtained as
white crystalline solids.
IR (KBr): ν = 3380 (w, νNH) cm–1. 1H NMR (300 MHz, C6D6,
˜
3
25 °C, TMS): δ = 1.03 [d, JH,H = 6.9 Hz, 12 H, CH(CH3)2], 1.19
[d, 3JH,H = 6.9 Hz, 12 H, CH(CH3)2], 1.54 (s, 6 H, CH3), 3.32 [sept.,
3JH,H = 6.9 Hz, 4 H, CH(CH3)2], 4.98 (s, 1 H, γ-CH), 6.16 (br., 2
H, NH), 6.57 (br. s, 2 H, p-Ph-H) 7.05–7.08 (m, 6 H, m-, p-Ar–H),
7.12–7.15 (m, 8 H, o-, m-Ph-H) ppm.13C NMR (75 MHz, C6D6,
25 °C, TMS): δ = 23.2 (CH3), 24.3, 24.5 [CH(CH3)2], 28.1
[CH(CH3)2], 95.9 (γ-CH), 114.9 (p-C of Ph), 116.0 (i-C of Ph),
124.5, 128.3, 128.8, 129.0, 140.2, 144.4 (o-, m-, p-C of Ph and i-,
o-, m-C of Ar), 169.8 (C = N) ppm. MS (EI): m/z (%) = 670 (6)
[M]+, 578 (100) [M – NHC6H5]+, 487 (52) [M – 2 NHC6H5]+.
LGa(NHEt)2 (1): Yield: 0.89 g (86%). M.p. 156–158 °C. IR (KBr):
ν = 3381 (w, νNH) cm–1. 1H NMR (300 MHz, C D , 25 °C, TMS):
˜
6
3
6
3
δ = –0.27 (t, JH,H = 7.3 Hz, 2 H, NH), 0.95 (t, JH,H = 7.1 Hz, 3
H, NHCH2CH3), 1.21 [d, JH,H = 6.8 Hz, 12 H, CH(CH3)2], 1.42
LGa(NHtBu)Cl (5): A solution of LiNHtBu (0.20 g, 2.53 mmol) in
THF (10 mL) was added dropwise to a solution of LGaCl2 (1.00 g,
1.79 mmol) in THF (10 mL) at –78 °C. The reaction mixture was
warmed to ambient temperature and stirred for an additional 6 h.
All the volatiles were removed in vacuo, and the crude product was
extracted with toluene and rinsed with hexane to obtained 5 as a
pale-yellow solid. Yield: 0.90 g (85%). M.p. 226–230 °C.
3
3
[d, JH,H = 6.8 Hz, 12 H, CH(CH3)2], 1.56 (s, 6 H, CH3), 2.90 (dq,
3JH,H = 7.1 Hz, JH,H = 7.3 Hz, 2 H, NHCH2CH3), 3.55 [sept.,
3
3JH,H = 6.8 Hz, 4 H, CH(CH3)2], 4.71 (s, 1 H, γ-CH), 7.05–7.15 (m,
6 H, m-, p-Ar-H) ppm. 13C NMR (75 MHz, C6D6, 25 °C, TMS):
δ = 21.7 (NHCH2CH3), 23.4 (CH3), 24.7, 25.4 [CH(CH3)2], 28.1
[CH(CH3)2], 40.9 (NHCH2), 95.9 (γ-CH), 124.3, 126.9 (m-, p-C of
Ar), 141.9 (i-C of Ar), 144.4 (o-C of Ar), 169.1 (C=N) ppm. MS
(EI): m/z (%) = 574 (3) [M]+, 530 (100) [M – NHEt]+.
C33H51ClGaN3 (594.95): calcd. C 66.62, H 8.64, N 7.06; found C
66.5, H 8.5, N 6.8. IR (KBr): ν = 3338 (w, νNH) cm–1. H NMR
1
˜
(300 MHz, C6D6, 25 °C, TMS): δ = –0.03 (br. s, 1 H, NH), 0.88 [s,
3
9 H, (CH3)3CNH], 1.03 [d, JH,H = 6.8 Hz, 6 H, CH(CH3)2], 1.19
LGa(NHiPr)2 (2): Yield: 0.69 g (64%). M.p. 152–154 °C.
3
3
[d, JH,H = 6.8 Hz, 6 H, CH(CH3)2], 1.42 [d, JH,H = 6.8 Hz, 6 H,
C35H57GaN4 (603.6): calcd. C 69.65, H 9.52, N 9.28; found C 69.3,
3
H 9.3, N 9.1. IR (KBr): ν = 3371 (w, νNH) cm–1. 1H NMR
CH(CH3)2], 1.53 [d, JH,H = 6.8 Hz, 6 H, CH(CH3)2], 1.55 (s, 6 H,
˜
3
3
CH3), 3.31 [sept., JH,H = 6.8 Hz, 2 H, CH(CH3)2], 3.78 [sept.,
(300 MHz, C6D6, 25 °C, TMS): δ = –0.13 (d, JH,H = 6.6 Hz, 2 H,
NH), 0.98 [d, JH,H = 6.0 Hz, 12 H, CHN(CH3)2] 1.20 [d, JH,H
6.9 Hz, 12 H, CH(CH3)2], 1.40 [d, JH,H = 6.9 Hz, 12 H, CH-
(CH3)2], 1.52 (s, 6 H, CH3), 3.22 [dsept., JH,H = 6.6 Hz, JH,H
3JH,H = 6.8 Hz, 2 H, CH(CH3)2], 4.79 (s, 1 H, γ-CH), 7.05–7.15
(m, 6 H, m-, p-Ar- H) ppm. 13C NMR (C6D6, 25 °C, TMS): δ =
23.7, 24.2, 24.7, 24.8 [CH(CH3)2], 26.6, 28.0 [CH(CH3)2], 29.0
(CH3), 34.2 [NC(CH3)3], 49.9 [NC(CH3)3], 96.7 (γ-CH), 123.9,
125.3, 127.6, 140.3, 143.4, 145.9 (i-, o-, m-, p-C of Ar), 169.6
(C=N) ppm. MS (EI): m/z (%) = 593 (9) [M]+, 521 (100) [M –
NHtBu]+.
3
3
=
3
3
3
=
3
6.0 Hz, 2 H, NCH(CH3)2], 3.65 [sept., JH,H = 6.6 Hz, 4 H,
CH(CH3)2], 4.79 (s, 1 H, γ-CH), 7.05–7.15 (m, 6 H, m-, p-Ar-
H) ppm. 13C NMR (75 MHz, C6D6, 25 °C, TMS): δ = 23.7
[CH(CH3)2], 24.5, 25.4 [CH(CH3)2], 27.8 [CH(CH3)2], 28.8 (CH3),
45.6 (NCH), 96.8 (γ-CH), 123.6, 124.2, 125.0, 126.6, 144.2 (i-, o-,
m-, p-C of Ar), 169.1 (C=N) ppm. MS (EI): m/z (%) = 602 (2)
[M]+, 544 (100) [M – NHiPr]+.
LGa(NHEt)Cl (6): Compound 6 was prepared in the same manner
as compounds 1–3 starting from MeLi (3.0 , 0.60 mL,
1.80 mmol), EtNH2 (2.0  in THF, 2.50 mL, 5.00 mmol), and
LGaCl2 (1.00 g, 1.79 mmol). Yield: 0.83 g (82%). M.p. 80–82 °C.
LGa(NHnBu)2 (3): Yield: 0.65 g (58%). M.p. 101–102 °C.
C37H61GaN4 (631.6): calcd. C 70.36, H 9.73, N 8.87; found C 70.0, C31H47ClGaN3 (566.90): calcd. C 65.68, H 8.36, N 7.41; found C
1
H 9.4, N 8.5. IR (KBr): ν = 3379 (w, νNH) cm–1. 1H NMR
65.9, H 8.4, N 7.1. IR (KBr): ν = 3335 (w, νNH) cm–1. H NMR
˜
˜
3
3
(300 MHz, C6D6, 25 °C, TMS): δ = –0.16 (t, JH,H = 7.4 Hz, 2 H, (300 MHz, C6D6, 25 °C, TMS): δ = –0.02 (t, JH,H = 7.2 Hz, 1 H,
NH) 0.60 (t, JH,H = 7.2 Hz, 3 H, CH3CH2NH) 1.07 [d, JH,H =
= 6.8 Hz, 12 H, CH(CH3)2], 1.43 [d, JH,H = 6.8 Hz, 12 H, 6.8 Hz, 6 H, CH(CH3)2], 1.21 [d, JH,H = 6.8 Hz, 6 H, CH(CH3)2],
1.38 [d, JH,H = 6.8 Hz, 6 H, CH(CH3)2], 1.54 [d, JH,H = 6.8 Hz,
6.9 Hz, 2 H, NHCH2CH3), 3.56 [sept., JH,H = 6.8 Hz, 4 H, 6 H, CH(CH3)2], 1.55 (s, 6 H, CH3), 2.64 (quint., JH,H = 7.2 Hz,
3
3
3
3
NH), 0.84 [t, JH,H = 6.9 Hz, 3 H, NH(CH2)3CH3], 1.22 [d, JH,H
3
3
3
3
3
3
CH(CH3)2], 1.56 (s, 6 H, CH3), 2.87 (dt, JH,H = 7.4 Hz, JH,H
=
3
3
3
CH(CH3)2], 4.72 (s, 1 H, γ-CH), 7.05–7.15 (m, 6 H, m-, p-Ar-
H) ppm. Remaining signals of the butyl CH2 groups could not be
observed. 13C NMR (75 MHz, C6D6, 25 °C, TMS): δ = 14.5
2 H, NHCH2CH3), 3.28 [sept., JH,H = 6.8 Hz, 2 H, CH(CH3)2],
3
3.78 [sept., JH,H = 6.8 Hz, 2 H, CH(CH3)2], 4.81 (s, 1 H, γ-CH),
7.05–7.17 (m, 6 H, m-, p-Ar-H) ppm. 13C NMR (C6D6, 25 °C,
4568
www.eurjic.org
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
Eur. J. Inorg. Chem. 2009, 4564–4571

β-Diketiminate Gallium Amides: Useful Synthons in Gallium Chemistry
TMS): δ = 23.5, 24.2, 24.5, 24.8 [CH(CH3)2], 26.8, 28.1 [CH-
EtNH2 (2.0  in THF, 2.42 mL, 4.84 mmol), and LAlCl2 (1.00 g,
(CH3)2], 28.6 (CH3), 29.0 (NCH2CH3), 39.7 (NCH2), 96.8 (γ-CH), 1.94 mmol). Yield: 0.64 g (62%). M.p. 126–128 °C. IR (KBr): ν =
˜
123.5, 123.9, 127.7, 140.1, 143.5, 145.7 (C of Ar), 170.0
3381 (w, νNH) cm–1. 1H NMR (300 MHz, C6D6, 25 °C, TMS): δ
3
3
(C=N) ppm. MS (EI): m/z (%) = 565 (6) [M]+, 550 (14) [M – = –0.29 (t, JH,H = 7.3 Hz, 2 H, NH), 0.98 (t, JH,H = 7.0 Hz, 3 H,
CH3]+, 506 (100) [M – NHEt – CH3]+.
NHCH2CH3), 1.25 [d, JH,H = 7.0 Hz, 12 H, CH(CH3)2], 1.46 [d,
3
3JH,H = 6.8 Hz, 12 H, CH(CH3)2], 1.61 (s, 6 H, CH3), 2.90 (dq,
LAl(NHEt)2 (7): Compound 7 was prepared in the same manner as
compounds 1–3, starting from MeLi (3.0 , 1.36 mL, 4.08 mmol),
3
3JH,H = 7.0 Hz, JH,H = 7.3 Hz, 2 H, NHCH2CH3), 3.59 [sept.,
Table 2. Crystallographic and data collection details for compounds 1–8.
1
2
3
4·0.5C7H8
Formula
Fw
Crystal system
Space group
T [K]
C33H53GaN4
575.51
monoclinic
P21/n
C35H57GaN4
603.57
monoclinic
P21
C37H61GaN4
631.62
monoclinic
P21/c
C44.50H57GaN4
717.66
orthorhombic
Pcca
173(2)
173(2)
100(2)
173(2)
λ [Å]
a [Å]
b [Å]
c [Å]
0.71073
0.71073
9.875(1)
16.478(2)
11.561(2)
111.31(2)
1752.6(4)
2
1.144
0.812
652
0.56ϫ0.40ϫ0.38
1.89–25.36
–11ՅhՅ11
–19ՅkՅ19
–9ՅlՅ13
10965
0.71073
0.71073
12.818(1)
16.470(2)
16.050(2)
105.70(1)
3261.9(6)
4
1.172
0.870
1240
0.39ϫ0.21ϫ0.15
1.81–25.37
–15ՅhՅ15
–19ՅkՅ19
–19ՅlՅ19
44002
12.947(2)
13.065(2)
20.945(3)
91.89(2)
3541.0(9)
4
1.185
0.807
1368
0.44ϫ0.25ϫ0.25
1.84–25.04
–15ՅhՅ15
–15ՅkՅ15
–24ՅlՅ24
24409
38.964(5)
11.938(2)
17.126(3)
90
7966(2)
8
1.197
0.726
3064
0.26ϫ0.18ϫ0.04
1.05–25.11
–46ՅhՅ46
–14ՅkՅ14
–20ՅlՅ20
61506
β [°]
V [Å3]
Z
Dcalcd. [gcm–3]
µ [mm–1]
F(000)
Crystal size [mm3]
θ range [°]
Index ranges
No. reflns collected
No. indep. reflns (Rint
)
5955 (0.0436)
5955/160/404
0.935
0.0315, 0.0757
0.0405, 0.0783
–
6151 (0.0291)
6151/302/465
0.900
0.0305, 0.0570
0.0351, 0.0579
–0.009(7)
0.346/–0.214
6187 (0.0518)
6187/429/476
1.015
0.0461, 0.1168
0.0568, 0.1225
–
7058 (0.1084)
7058/625/596
1.042
0.0546, 0.1060
0.0850, 0.1173
–
No. data/restr./parameters
GoF on F2
[b]
R1,[a] wR2[b] [I Ͼ 2σ(I)]
R1,[a] wR2 (all data)
Abs. struct. par.
Largest diff. peak/hole [eÅ–3]
0.399/–0.239
1.846/–0.496
0.392/–0.342
5
6
7
8
Formula
Fw
Crystal system
Space group
T [K]
C33H51ClGaN3
594.94
monoclinic
P21/m
C31H47ClGaN3
566.89
monoclinic
P21/c
C33H53AlN4
532.77
monoclinic
P21/n
C33H51GaN2O2
577.48
monoclinic
P21/n
173(2)
173(2)
100(2)
100(2)
λ [Å]
a [Å]
b [Å]
c [Å]
0.71073
9.079(2)
20.265(3)
9.842(2)
113.05(2)
1666.2(6)
2
1.186
0.930
636
0.34ϫ0.31ϫ0.24
2.01–25.36
–10ՅhՅ10
–23ՅkՅ24
–11ՅlՅ11
11327
0.71073
0.71073
0.71073
12.746(2)
13.538(2)
18.782(3)
107.00(2)
3099.3(9)
4
1.215
0.997
1208
0.36ϫ0.16ϫ0.15
1.67–25.03
–14ՅhՅ15
–16ՅkՅ15
–22ՅlՅ22
20111
12.603(2)
16.464(3)
15.966(3)
105.17(3)
3197.4(10)
4
1.107
0.090
1168
0.39ϫ0.34ϫ0.32
1.81–25.03
–15ՅhՅ15
–19ՅkՅ19
–18ՅlՅ19
20740
11.854(2)
16.604(2)
16.518(3)
104.21(2)
3151.7(9)
4
1.217
0.903
1240
0.33ϫ0.23ϫ0.23
1.77–25.36
–14ՅhՅ14
–20ՅkՅ19
–19ՅlՅ19
25238
β [°]
V [Å3]
Z
Dcalcd. [gcm–3]
µ [mm–1]
F(000)
Crystal size [mm3]
θ range [°]
Index ranges
No. reflns collected
No. indep. reflns (Rint
)
3114 (0.0388)
3114/253/272
1.048
0.0348, 0.0806
0.0405, 0.0833
0.592/–0.222
5458 (0.0724)
5458/67/365
1.001
0.0543, 0.1187
0.0823, 0.1329
0.823/–0.272
5613 (0.0501)
5613/2/364
1.046
0.0475, 0.1127
0.0614, 0.1210
0.425/–0.208
5732 (0.0330)
5732/87/388
1.033
0.0299, 0.0739
0.0344, 0.0765
0.417/–0.170
No. data/restr./parameters
GoF on F2
R1,[a] wR2[b] [I Ͼ 2σ(I)]
[b]
R1,[a] wR2 (all data)
Largest diff. peak/hole [eÅ–3]
[a] R1 = Σ||Fo| – | Fc||/Σ|Fo|. [b] wR2 = [Σw (Fo – Fc ) /Σ(Fo2)2]1/2
.
2
2 2
Eur. J. Inorg. Chem. 2009, 4564–4571
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
4569

D. Solis-Ibarra, A. P. Gómora-Figueroa, N. Zavala-Segovia, V. Jancik
FULL PAPER
3JH,H = 6.8 Hz, 4 H, CH(CH3)2], 4.92 (s, 1 H, γ-CH), 7.15–7.20 (m, tance restraints (SADI) when applicable. The Flack parameter[35]
6 H, m-, p-Ar-H) ppm. 13C NMR (75 MHz, C6D6, 25 °C, TMS): [–0.009(7)] was used to determine the correct enantiomorph of
δ = 21.5 (NHCH2CH3), 23.4 (CH3), 24.5, 25.1 [CH(CH3)2], 27.8 compound 2. The disordered groups (2NHEt in 1, 2NHiP and
[CH(CH3)2], 38.5 (NHCH2), 96.9 (γ-CH), 123.9, 126.3 (m-, p-C of PhiPr in 2, 2nBu and PhiPr in 3, 2,6-iPr2C6H3 and toluene in 4,
Ar), 141.3 (i-C of Ar), 144.3 (o-C of Ar), 169.2 (C=N) ppm. MS
NHtBu and PhiPr in 5, NHEt in 6, PhiPr in 8) were refined using
geometry and distance restraints (SAME, SADI) together with the
restraints for the Uij values (SIMU, DELU). Table 2 contains rel-
evant crystallographic and data collection details for compounds
1–8. CCDC-735439 (for 1), -735440 (for 2), -735441 (for 3), -735442
(for 4), -735443 (for 5), -735444 (for 6), -735445 (for 7), and -735446
(for 8) contain the supplementary crystallographic data for this pa-
per. These data can be obtained free of charge from The Cambridge
Crystallographic Data Centre via www.ccdc.cam.ac.uk/data_
request/cif.
(EI): m/z (%) = 532 (2) [M]+, 488 (100) [M – NHEt]+.
LGa(OEt)2 (8): A solution of ethanol (0.30 mL, 5.14 mmol) in
THF (15 mL) was added dropwise to a solution of 1 (1.00 g,
1.74 mmol) in THF. The reaction mixture was stirred for 2 h, and 7
was obtained as a white crystalline solid after removing all volatiles.
Yield: 0.95 g (95%). M.p. 156–158 °C. C33H51GaN2O2 (577.5):
calcd. C 68.63, H 8.90, N 4.85; found C 68.4, H 8.8, N 4.7. 1H
3
NMR (300 MHz, C6D6, 25 °C, TMS): δ = 1.09 (t, JH,H = 7.0 Hz,
3
3 H, OCH2CH3), 1.16 [d, JH,H = 6.9 Hz, 12 H, CH(CH3)2], 1.48
[d, 3JH,H = 6.6 Hz, 12 H, CH(CH3)2], 1.52 (s, 6 H, CH3), 3.52 [sept.,
3
3JH,H = 6.9 Hz, 4 H, CH(CH3)2], 3.84 (q, JH,H = 7.0 Hz, 2 H,
Acknowledgments
OCH2CH3), 4.73 (s, 1 H, γ-CH), 7.10–7.20 (m, 6 H, m-, p-Ar-H)
ppm. 13C NMR (75 MHz, C6D6, 25 °C, TMS):
δ = 20.7
Financial support from the Dirección General de Asuntos del Per-
sonal – Universidad Nacional Autónoma de México (DGAPA-
UNAM, PAPIIT grant no. IN205108) and Consejo Nacional de
Ciencia y Tecnología (CONACyT, grant no. 79531) is greatly ac-
knowledged.
(OCH2CH3), 23.4 (CH3), 24.7, 25.0 [CH(CH3)2], 28.6 [CH(CH3)2],
60.9 (OCH2), 96.0 (γ-CH), 124.3, 128.3, 140.7 (C of Ar), 144.5 (o-
C of Ar), 170.5 (C=N) ppm. MS (EI): m/z (%) = 576 (2) [M]+, 531
(33) [M – OEt]+, 515 (50) [M – OEt – Me – H]+, 486 (78) [M –
2OEt]+, 471 (100) [M – 2OEt – Me]+.
LGa(OEt)Cl (9): Ethanol (0.5  in THF, 2.0 mL, 1.00 mmol) was
dissolved in THF (10 mL) and added dropwise to a solution of 5
(0.29 g, 0.49 mmol) in THF (15 mL) at –78 °C. The reaction mix-
ture was warmed to ambient temperature and stirred for overnight.
All volatiles were removed in vacuo, and 9 was obtained as a white
solid after washing the crude product with hexane. Yield: 0.27 g
(93%). M.p. 173–175 °C. C31H46ClGaN2O (567.9): calcd. C 65.57,
[1] P. A. Gómora-Figueroa, V. Jancik, R. Cea-Olivares, R. A. Tos-
cano, Inorg. Chem. 2007, 46, 10749–10753.
[2] V. Jancik, F. Rascón-Cruz, R. Cea-Olivares, R. A. Toscano,
Chem. Commun. 2007, 4528–4530.
[3] F. Rascón-Cruz, R. Huerta-Lavorie, V. Jancik, R. Cea-Olivares,
R. A. Toscano, Dalton Trans. 2009, 7, 1195–1200.
[4] C. Cui, H. W. Roesky, H. Hao, H.-G. Schmidt, M. Noltenme-
yer, Angew. Chem. Int. Ed. 2000, 39, 1815–1817.
[5] V. Jancik, Y. Peng, H. W. Roesky, J. Li, D. Neculai, A. M. Nec-
ulai, R. Herbst-Irmer, J. Am. Chem. Soc. 2003, 125, 1452–1453.
[6] S. Singh, V. Jancik, H. W. Roesky, Inorg. Chem. 2006, 45, 949–
951.
1
H 8.16, N 4.93; found C 65.3, H 8.1, N 4.8. H NMR (300 MHz,
3
C6D6, 25 °C, TMS): δ = 0.77 (t, JH,H = 6.9 Hz, 3 H, OCH2CH3),
3
3
1.14 [d, JH,H = 6.8 Hz, 6 H, CH(CH3)2], 1.19 [d, JH,H = 6.8 Hz,
3
6 H, CH(CH3)2], 1.53 [d, JH,H = 6.6 Hz, 12 H, CH(CH3)2], 1.56
(s, 6 H, CH3), 3.38 [sept., JH,H = 6.8 Hz, 2 H, CH(CH3)2], 3.61 [7] A. J. Arduengo III, H. Bock, H. Chen, M. Denk, D. A. Dixon,
3
3
3
J. C. Green, W. A. Herrmann, N. L. Jones, M. Wagner, R.
West, J. Am. Chem. Soc. 1994, 116, 6641–6649.
[8] V. Jancik, L. W. Pineda, A. C. Stückl, H. W. Roesky, R. Herbst-
Irmer, Organometallics 2005, 24, 1510–1515.
[9] N. J. Hardman, P. P. Power, Inorg. Chem. 2001, 40, 2474–2475.
[10] N. J. Hardman, P. P. Power, Chem. Commun. 2001, 13, 1184–
1185.
[11] M. Stender, B. E. Eichler, N. J. Hardman, P. P. Power, J. Prust,
M. Noltenmeyer, H. W. Roesky, Inorg. Chem. 2001, 40, 2794–
2799.
[sept., JH,H = 6.6 Hz, 2 H, CH(CH3)2], 3.64 (q, JH,H = 6.9 Hz, 2
H, OCH2CH3), 4.78 (s, 1 H, γ-CH), 7.10–7.20 (m, 6 H, m-, p-Ar-
H) ppm. 13C NMR (75 MHz, C6D6, 25 °C, TMS): δ = 19.6
(OCH2CH3), 23.8 (CH3), 24.3, 24.8, 24.9, 25.6 [CH(CH3)2], 28.1,
28.5 [CH(CH3)2], 60.4 (OCH2), 96.5 (γ-CH), 124.2, 124.5, 127.5,
138.9 (C of Ar), 144.5, 144.7 (o-C of Ar), 170.9 (C=N) ppm. MS
(EI): m/z (%) = 566 (3) [M]+, 531 (10) [M – Cl]+, 521 (88) [M –
OC2H4]+, 506 (100) [M – OC2H4 – CH3]+, 471 (39) [M – OC2H5 –
Cl – Me]+.
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Received: June 16, 2009
Published Online: September 15, 2009
Eur. J. Inorg. Chem. 2009, 4564–4571
© 2009 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.eurjic.org
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