Synthesis of heavier group 14 metal compounds from 2,6- lutidylbis(phosphoranosulfide)

Article abstract of DOI:10.1021/om1001167

The synthesis and characterization of various novel group 14 metal compounds derived from 2,6-lutidylbisphosphoranosulfide, [(S - PPr ⁱ₂CH₂)₂C₅H ₃N-2,6] (1), are reported. The monoanionic b

Full text of DOI:10.1021/om1001167

1890 Organometallics 2010, 29, 1890–1896
DOI: 10.1021/om1001167
Synthesis of Heavier Group 14 Metal Compounds from
2,6-Lutidylbis(phosphoranosulfide)
Wing-Por Leung,* Kwok-Wai Kan, and Thomas C. W. Mak
Department of Chemistry, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong,
People’s Republic of China
Received February 12, 2010
The synthesis and characterization of various novel group 14 metal compounds derived from 2,6-
lutidylbisphosphoranosulfide, [(SdPPri2CH2)2C5H3N-2,6] (1), are reported. The monoanionic bis-
(thiophosphinoyl) lithium complex [Li{(SdPPri2CH)(SdPPri2CH2)C5H3N-2,6}(Et2O)] (2) has been
prepared from the reaction of 1 with an equimolar amount of nBuLi in THF. Treatment of 1 with
1 equiv of M{N(SiMe3)2}2 (M = Sn, Pb) afforded the 1,3-distannacyclobutane [{2-{Sn{C(Pri2Pd
S)}}-6-{CH2(Pri2PdS)}}C5H3N]2 (3) and 1,3-diplumbacyclobutane [{2-{Pb{C(Pri2PdS)}}-6-{CH2-
(Pri2PdS)}}-C5H3N]2 (4), respectively. The metathesis reaction of 2 with GeCl2 (dioxane) and
3
SnCl2 gave the unexpected digermylgermylene Ge[GeCl2{(SdPPri2CH)(SdPPri2CH2)C5H3N-2,6}]2
(5) and ionic [2,6-lutidylbis(thiophosphinoyl)methanide]tin(II) trichlorostannate [{C5H3N-2,6-
(CH2PPri2dS)(CHPPri2dS)}Sn]þ[SnCl3]- (6), respectively. The X-ray structures of 2-6 have been
determined by X-ray crystallography.
Introduction
Zr(IV), Sm(III), and Tm(III) metal centers.4-8 Stable carbe-
noids and dicarbenoids can also be prepared from oxida-
tion of the dianion.9,10 Nevertheless, thiophosphinoyl li-
gands have rarely been employed as ancillary ligands in
synthesizing group 14 metal compounds. Herein, we report
the synthesis of a novel 2,6-lutidylbis(phosphoranosulfide),
[(SdPPri2CH2)2C5H3N-2,6] (1), used as a ligand precursor
for several group 14 metal complexes.
The coordination chemistry of thiophosphinoyl transition
metal complexes has been studied by several research groups
in view of the importance of metal-sulfur interaction and
different bonding modes of various metal adducts.1 Phos-
phoranosulfides can be deprotonated by strong base to give
anionic species or novel metal compounds. An unprece-
dented organoaluminum compound has been prepared by
Robinson et al. through in situ double deprotonation of
neutral bis(diphenylthiophosphinoyl)methane with AlMe3.2
Using the same ligand, Le Floch and co-workers reported the
synthesis of the bis(diphenylthiophosphinoyl)methanediide
dianion3 and its coordination chemistry with Pd(II), Ru(II),
Results and Discussion
Synthesis of2,6-Lutidylbis(phosphoranosulfide) and a Mono-
anionic Bis(thiophosphinoyl) Lithium Complex. The dipho-
sphine [(PPri2CH2)2C5H3N-2,6] was prepared according to
the modified procedure.11 Treatment of it with 2 equiv of
elemental sulfur in toluene at 60 °C afforded the novel 2,6-
lutidylbis(phosphoranosulfide) [(SdPPri2CH2)2C5H3N-2,6]
(1) (Scheme 1). Compound 1 was isolated as a white crystal-
line solid after recrystallization from toluene or diethyl
ether. The reaction of 1 with 1 equiv of nBuLi in THF gave
the monoanionic bis(thiophosphinoyl) lithium complex
[Li{(SdPPri2CH)(SdPPri2CH2)C5H3N-2,6}(Et2O)] (2)
(Scheme 1).
*To whom correspondence should be addressed. E-mail: kevinleung@
cuhk.edu.hk.
(1) Selected examples of thiophosphinoyl metal complexes: (a) Aucott,
S. M.; Slawin, A. M. Z.; Woollins, J. D. Eur. J. Inorg. Chem. 2002, 2408.
(b) Faller, J. W.; Lloret-Fillol, J.; Parr, J. New J. Chem. 2002, 26, 883.
(c) Suranna, G. P.; Mastrorilli, P.; Nobile, C. F.; Keim, W. Inorg. Chim. Acta
2000, 305, 151. (d) Grim, S. O.; Walton, E. D. Inorg. Chem. 1980, 19, 1982.
ꢀ
(e) Doux, M.; Bouet, C.; Mezailles, N.; Ricard, L.; Le Floch, P. Organome-
ꢀ
tallics 2002, 21, 2785. (f) Doux, M.; Mezailles, N.; Melaimi, M.; Ricard, L.;
Le Floch, P. Chem. Commun. 2002, 1566. (g) Chivers, T.; Fedorchuk, C.;
Krahn, M.; Parvez, M.; Schatte, G. Inorg. Chem. 2001, 40, 1936. (h) Rufanov,
K. A.; Ziemer, B.; Meisel, M. Dalton Trans. 2004, 3808. (i) Lobana, T. S.;
Sandhu, M. K.; Tiekink, E. R. T. J. Chem. Soc., Dalton Trans. 1988, 1401.
(j) Baker, P. K.; Clark, A. I.; Drew, M. G. B.; Durrant, M. C.; Richards, R. L.
Polyhedron 1998, 17, 1407. (k) Lobana, T. S.; Verma, R.; Singh, A.; Shikha,
M.; Castineiras, A Polyhedron 2002, 21, 205. (l) Schumann, H. J. Organomet.
ꢀ
(5) Cantat, T.; Demange, M.; Mezailles, N.; Ricard, L.; Jean, Y.;
Le Floch, P. Organometallics 2005, 24, 4838.
(6) Cantat, T.; Jaroschik, F.; Ricard, L.; Le Floch, P; Nief, F.;
ꢀ
Mezailles, N. Organometallics 2006, 25, 1329.
(7) Cantat, T.; Jaroschik, F.; Nief, F.; Ricard, L.; Mezailles, N.;
ꢀ
ꢀ
Chem. 1987, 320, 145. (m) Arliguie, T.; Blug, M.; Le Floch, P.; Mezailles, N.;
ꢀ
Thuery, P.; Ephritikhine, M. Organometallics 2008, 27, 4158.
(2) Robinson, G. H.; Self, M. F.; Pennington, W. T.; Sangokoya,
Le Floch, P. Chem. Commun. 2005, 5178.
ꢀ
(8) Cantat, T.; Ricard, L.; Mezailles, N.; Le Floch, P. Organometal-
S. A. Organometallics 1988, 7, 2424.
(3) Cantat, T.; Ricard, L.; Le Floch, P.; Mezailles, N. Organometal-
lics 2006, 25, 6030.
(9) Cantat, T.; Jacques, X.; Ricard, L.; Le Goff, X. F.; Mezailles, N.;
ꢀ
ꢀ
lics 2006, 25, 4965.
(4) Cantat, T.; Mezailles, N.; Ricard, L.; Jean, Y.; Le Floch, P.
Angew. Chem., Int. Ed. 2004, 43, 6382.
Le Floch, P. Angew. Chem., Int. Ed. 2007, 46, 5947.
(10) Konu, J.; Chivers, T. Chem. Commun. 2008, 4995.
(11) Ziessel, R. Tetrahedron Lett. 1989, 30, 463.
ꢀ
r
pubs.acs.org/Organometallics
Published on Web 03/29/2010
2010 American Chemical Society

Article
Organometallics, Vol. 29, No. 8, 2010 1891
Scheme 1
Scheme 2
Scheme 3
Synthesis of 1,3-Distannacyclobutane and 1,3-Diplumbacy-
clobutane. Reaction of 1 with 1 equiv of M{N(SiMe3)2}2
(M = Sn, Pb) afforded the 1,3-distannacyclobutane [{2-{Sn-
{C(Pri2PdS)}}-6-{CH2(Pri2PdS)}}C5H3N]2 (3) and 1,3-di-
plumbacyclobutane [{2-{Pb{C(Pri2PdS)}}-6-{CH2(Pri2Pd
S)}}C5H3N]2 (4), respectively (Scheme 2). It is proposed
that the reactions proceed through the unstable metallavi-
nylidenes. Elimination of 2 equiv of hexamethyldisilazane
formed the intermediate metallavinylidene [{2-{:MdC(Pri2-
PdS)}-6-{CH2(Pri2PdS)}}-C5H3N] (M = Sn, Pb). Subse-
quently, this intermediate underwent a head-to-tail cyclodi-
merization to form the 1,3-dimetallacyclobutane. Our group
has reported the synthesis of similar 1,3-dimetallacyclobu-
tanes using phosphoranoimine as the ligand backbone.12-14
Synthesis of Digermylgermylene. Metathesis reaction of 2
Synthesis of Ionic [2,6-Lutidylbis(thiophosphinoyl)methanide]-
tin(II) Trichlorostannate. The reaction of 2 with excess SnCl2
afforded the ionic bis(thiophosphinoyl)methanide tin(II) tri-
chlorostannate [{C5H3N-2,6-(CH2PPri2dS)(CHPPri2dS)}-
Snþ][SnCl3-] (6) (Scheme 4). The first step probably involved
the formation of the chlorostannylene [{C5H3N-2,6-(CH2-
PPri2dS)(CHPPri2dS)}SnCl] (III) by a metathesis reaction
between 2 and SnCl2. The excess SnCl2 is then reacted as a
chloride abstracting agent with compound III to yield com-
pound 6. The chloride-abstracting properties of SnCl2 have
been reported in the literature.16
Spectroscopic Properties. Compounds 1-6 were isolated
as colorless, pale yellow, red, or orange crystalline solids.
They are air-sensitive and soluble in THF and CH2Cl2 but
sparingly soluble in Et2O. The 1H NMR and 13C{1H} NMR
spectra of 1 are consistent with the compounds having the
with 1.5 equiv of GeCl2 (dioxane) afforded the novel diger-
3
mylgermylene Ge[GeCl2{(SdPPri2CH)(SdPPri2CH2)C5H3-
N-2,6}]2 (5) (Scheme 3). It is suggested that the intermediate
[GeCl{(SdPPri2CH)(SdPPri2CH2)C5H3N-2,6}] (I) formed
underwent an insertion reaction into the GeII-Cl bond
of GeCl2 (dioxane) to give [GeCl(GeCl2){(SdPPri2CH)(Sd
3
PPri2CH2)C5H3N-2,6}] (II). The GeII-Cl bond of II then
further reacted with I to form digermylgermylene. A similar
insertion reaction of the Ge-Cl bond has been reported by
Kira and co-workers.15 Attempts to isolate I by reacting
equimolar amounts of 2 and GeCl2 (dioxane) were unsuc-
3
cessful; a mixture of 5 and I was obtained, as shown by
31P{1H} NMR spectroscopy.
(12) Leung, W.-P.; Wong, K.-W.; Wang, Z.-X.; Mak, T. C. W.
Organometallics 2006, 25, 2037.
(13) Leung, W.-P.; Wang, Z.-X.; Li, H.-W.; Yang, Q.-C.; Mak,
T. C. W. J. Am. Chem. Soc. 2001, 123, 8123.
(14) Leung, W.-P.; Wang, Z.-X.; Li, H.-W.; Mak, T. C. W. Angew.
Chem., Int. Ed. 2001, 40, 2501.
(15) Iwamoto, T.; Masuda, H.; Kabuto, C.; Kira, M. Organometal-
(16) (a) Farkas, E.; Kollar, L.; Moret, M.; Sironi, A. Organometallics
1996, 15, 1345. (b) Tian, X.; Pape, T.; Mitzel, N. W. Z. Naturforsch., B:
Chem. Sci. 2004, 59, 1524. (c) Veith, M.; Goedicke, B.; Huch, V. Z. Anorg.
Allg. Chem. 1989, 579, 87.
lics 2005, 24, 197.

1892 Organometallics, Vol. 29, No. 8, 2010
Leung et al.
Scheme 4
Figure 1. Molecular structure of [Li{(SdPPri2CH)(SdPPri2-
CH2)C5H3N-2,6}(Et2O)] (2) (30% probability ellipsoids).
1
2,6-lutidyl ligand backbone. The H NMR spectrum of 2
displayed two different isopropyl groups, which is consistent
with the solid-state structures. The 31P{1H} NMR spectrum
of 1 displayed two signals at δ 58.36 and 71.29 ppm. The 1H
NMR and 13C{1H} NMR spectra of 3 and 4 are normal. The
31P{1H} NMR spectrum of 3 displayed two signals at δ 69.70
and 84.29 ppm with tin satellites (2J(31P-119Sn) = 1221 Hz).
The 31P{1H} NMR spectrum of 4 displayed two signals at
δ 65.16 and 74.57 ppm with lead satellites (2J(31P-207Pb) =
1880 Hz). These are consistent with the solid-state struc-
tures of 3 and 4 having two different phosphorus environ-
ments. Owing to the low solubility of 3 and 4, we were unable
to detect the 119Sn-31P coupling and 207Pb-31P coupling
signals from the corresponding 119Sn{1H} and 207Pb{1H}
NMR spectra. The 119Sn{1H} NMR signal of 3 and 207Pb-
{1H} NMR signal of 4 were detected with low intensity at
-4.02 and 2193.4 ppm, respectively.
Figure 2. Molecular structure of [{2-{Sn{C(Pri2PdS)}}-6-
{CH2(Pri2PdS)}}C5H3N]2 (3) (30% probability ellipsoids).
The 1H NMR and 13C{1H} NMR spectra of 5 both
displayed signals due to the 2,6-lutidylbis(phosphoranosul-
fide) ligand backbone. The 31P{1H} NMR spectrum of 5
showed two signals at δ 78.92 and 84.28 ppm, which do not
correspond to the X-ray structure. In the solid-state structure
there are four different phosphorus atoms. However, this is
not reflected in solution, where only two 31P resonances are
observed. Apparently, the intramolecular PdSfGe coordi-
nation is kinetically labile and the dissociation process is
fast on the NMR time scale at room temperature. We have
carried out the low- temperature 31P NMR study of 5 in d8-
THF. There was no obvious change in the two signals
at -60 °C.
The 1H and 13C{1H} NMR spectra of 6 displayed signals
assignable to the ligand backbone. The 31P{1H} NMR
spectrum of 6 displayed two signals of δ 81.37 and 83.82
ppm which are assignable to two different phosphorus
environments and are consistent with the solid-state struc-
ture. Due to the low solubility of compound 6 in THF, tin
satellites were not observed in the 31P{1H} NMR spectrum.
The 119Sn{1H} NMR spectrum of 6 showed two signals at
δ -119.94 (2J(119Sn-31P) = 140.3 Hz) and -97.50 ppm,
which correspond to the stannyl cation and trichlorostan-
nate anion, respectively.
Figure 3. Molecular structure of [{2-{Pb{C(Pri2PdS)}}-6-
{CH2(Pri2PdS)}}C5H3N]2 (4) (30% probability ellipsoids).
˚
P(1)-C(6) bond distance of 1.707(8) A and P(1)-S(1) bond
distance of 2.009(3) A in 2 are different from those found in 3
˚
˚
˚
X-ray Structures. The molecular structures of 2-6 are
shown in Figures 1-5, respectively. Selected bond distances
(A) and angles (deg) are given in Tables 1 and 2. Compound 2
(P-C = 1.835(2) A; P-S = 1.941(1) A), suggesting the
charge delocalization within the C-P-S skeleton.
˚
Compound 3 consists of two tin atoms bridged by two
methanediide carbon atoms, forming a 1,3-Sn2C2 four-
membered ring. The two pyridyl nitrogen atoms of the ligand
coordinate to the trigonal-pyramidal tin centers to form
is a lithium complex consisting of a lithium center which is
bonded to the ligand in S,N,S0-chelation and coordinated
to one Et2O molecule with a tetrahedral geometry. The

Article
Organometallics, Vol. 29, No. 8, 2010 1893
˚
Table 1. Selected Bond Distances (A) and Angles (deg) for
Compounds 2 and 3a
[Li{(SdPPri2CH)(SdPPri2CH2)C5H3N-2,6}(Et2O)] (2)
Li(1)-O(1)
Li(1)-N(1)
Li(1)-S(1)
Li(1)-S(2)
N(1)-C(5)
1.977(2)
2.037(1)
2.393(1)
2.556(2)
1.357(8)
N(1)-C(1)
P(1)-C(6)
P(1)-S(1)
P(2)-C(13)
P(2)-S(2)
1.386(8)
1.707(8)
2.009(3)
1.819(8)
1.967(3)
Figure 4. Molecular structure of Ge[GeCl2{(SdPPri2CH)(Sd
PPri2CH2)C5H3N-2,6}]2 (5) (30% probability ellipsoids).
O(1)-Li(1)-N(1)
O(1)-Li(1)-S(1)
N(1)-Li(1)-S(1)
O(1)-Li(1)-S(2)
N(1)-Li(1)-S(2)
108.6(7)
107.6(7)
113.5(5)
113.2(6)
100.3(6)
S(1)-Li(1)-S(2)
C(5)-N(1)-C(1)
C(6)-P(1)-S(1)
C(13)-P(2)-S(2)
113.5(5)
117.4(6)
118.2(3)
113.6(3)
[{2-{Sn{C(Pri2PdS)}}-6-{CH2(Pri2PdS)}}C5H3N]2 (3)
Sn(1)-C(6)
Sn(1)-C(6A)
Sn(1)-N(1)
P(1)-C(6)
2.294(2)
2.322(2)
2.400(2)
1.758(2)
P(2)-C(13)
P(1)-S(1)
P(2)-S(2)
1.835(2)
1.987(8)
1.941(1)
C(6)-Sn(1)-C(6A)
C(6)-Sn(1)-N(1)
C(6A)-Sn(1)-N(1)
Sn(1)-C(6)-Sn(1A)
86.7(7)
88.8(6)
59.1(5)
90.7(7)
C(6)-P(1)-S(1)
C(13)-P(2)-S(2)
P(1)-C(6)-Sn(1)
P(1)-C(6)-Sn(1A)
105.8(7)
113.8(9)
104.6(8)
119.4(9)
Figure 5. Molecular structure of [{C5H3N-2,6-(CH2PPri2dS)-
(CHPPri2dS)}Snþ][SnCl3-] (6) (30% probability ellipsoids).
Sn(1)-C(6)
2.294(2)
P(2)-C(13)
1.835(2)
a Symmetry transformations used to generate equivalent atoms: -x þ
3
2, y, -z þ /2.
SnCCN four-membered rings. These SnCCN rings together
with the Sn2C2 ring, as the base, form a structure framework
similar to an “open box”. The Sn2C2 ring is nonplanar, as
indicated by the angle sum of 354.7°. The average Sn-N
2.411 A)13 and 1,3-[Pb{C(Ph2PdNSiMe3)2}]2 (Pb-N = 2.647
˚
14
˚
˚
A; Pb-C = 2.494 A).
Compound 5 is a homoleptic germylene with two germyl
substituents, featuring a GeIV-GeII-GeIV linkage. The geo-
metry around the two germanium(IV) centers are distorted
tetrahedral, while the germanium(II) center displays a trigonal-
pyramidal geometry. It is noteworthy that the angles Ge(2)-
Ge(1)-Ge(3) = 89.4(2)°, Ge(2)-Ge(1)-S(1) = 82.8(3)°, and
Ge(3)-Ge(1)-S(1) = 86.4(3)° are close to 90°. This shows that
the germanium(II) center is almost nonhybridized. The lone
pair occupies an orbital with high s character, and the σ bonds
to the germyl substituents are formed by using p orbitals at the
germanium(II) center.21 The average GeII-GeIV bond distance
˚
bond distance of 2.400 A and average Sn-C bond distance of
i
2.308 A in 3 are comparable to those found in 1,3-[Sn{C(Pr 2-
˚
13
˚
˚
PdNSiMe3)(2-Py)}]2 (Sn-N = 2.470 A; Sn-C = 2.325 A)
and1,3-[Sn{C(Ph2PdNSiMe3)2}]2 (Sn-N=2.462A;Sn-C=
˚
14
˚
˚
2.376 A). The Sn-Sn distance of 3.283(2) A in 3 is similar
to those found in the previous 1,3-distannacyclobutanes
(3.28113 and 3.290 A ). It is shorter than the sum of the
˚
14
17
˚
˚
van der Waals radius of 4.4 A but is in excess of the 2.81 A
distance in elemental tin.18 This suggested that a weak
Sn-Sn interaction is possible in 3.
Compound 4 consists of a 1,3-diplumbacyclobutane ring
which is similar to the molecular structure of 3. With the
Pb2C2 group as the base, the PbCPS and PbCCN rings form
the flaps of an “open box”-like structure framework, which is
similar to that of 2. The coordination of the metal centers in 4
is somewhat different from that of 3. The two thio sulfur
atoms and two pyridyl nitrogen atoms of the ligand coordi-
nate to the four-coordinated lead center to form PbCPS and
PbCCN four-membered rings. The additional coordination
from the thio groups is presumably due to the larger atomic
size of the Pb(II) atom. The lead centers adopt a distorted-
square-pyramidal geometry. The average Pb-S bond distance
˚
˚
of 2.480 A in 5 is comparable to that of 2.544(7) A in C6H3-
22
2,6-(C6H2-2,4,6-Me3)2GeGe(But)3 and 2.449(1) A in [{μ-
˚
(Me3Si)C(PMe2)2}2Ge2]2GeCl2.23 The average GeIV-C bond
˚
˚
distance of 2.005 A is slightly longer than that of 1.924(7) A in
[Ge{μ-C(C5H4N-2)C(Ph)N(SiMe3)}Cl2]2,24 which may be
due to the steric repulsion between two ligands. The average
IV
˚
Ge -Cl bond distance of 2.192 A is in good agreement with
24
˚
that of 2.180 A in [{(C5H4N-2)C(H)C(Ph)N}(μ-GeCl2)2].
The two functionalized pyridines remain uncoordinated, which
may result from the steric crowding at the germanium centers.
The hydrogen atoms of the pyridine ring are nonequivalent,
which may be due to the restricted rotation caused by steric
hindrance.
Compound 6 is an ionic tin(II) compound consisting of a
stannyl cation and a trichlorostannate anion. The geometry
around the tin center in the stannyl cation is distorted
˚
˚
of 3.050 A in 4 is similar to that of 2.964 A in [Pb{SO(PPh2)2-
N}2]19 and 3.093 A in [Pb{S2P-(OC6H11)2}2]n.20 The average
˚
˚
Pb-N bond distance of 2.547 A and average Pb-C bond dis-
tance of 2.423 A in 4 are comparable to those found in 1,3-
˚
i
˚
[Pb{C(Pr 2PdNSiMe3)(2-Py)}]2 (Pb-N = 2.594 A; Pb-C =
(21) Jutzi, P.; Keitemeyer, S.; Neumann, B.; Stammler, H.-G. Orga-
nometallics 1999, 19, 4778.
(22) Setaka, W.; Sakamoto, K.; Kira, M.; Power, P. P. Organome-
(17) Bondi, A. J. Phys. Chem. 1964, 48, 441.
(18) Wells, A. F. Structural Inorganic Chemistry, 5th ed.; Clarendon:
Oxford, U.K., 1984; p 1279.
tallics 2001, 20, 4460.
(23) Karsch, H. H.; Deubelly, B.; Riede, J.; Muller, G. Angew. Chem.,
ꢀ
€
(19) Garcıa-Montalvo, V.; Cea-Olivares, R.; Espinosa-Perez, G.
Polyhedron 1996, 15, 829.
(20) Larsson, A. C.; Ivanov, A. V; Antzutkin, O. N; Gerasimenko,
Int. Ed. 1987, 26, 674.
(24) Leung, W.-P.; So, C.-W.; Wu, Y.-S.; Li, H.-W.; Mak, T. C. W.
A. V; Forsling, W. Inorg. Chim. Acta 2004, 357, 2510.
Eur. J. Inorg. Chem. 2005, 513.

1894 Organometallics, Vol. 29, No. 8, 2010
Leung et al.
distance of 2.478 A in the trichlorostannate anion is similar
˚
Table 2. Selected Bond Distances (A) and Angles (deg) for
˚
t
28
˚
Compounds 4-6
to that of 2.474(4) A in [Sn9{η-C5Me4(SiMe2Bu )}6Cl12].
[{2-{Pb{C(Pri2PdS)}}-6-{CH2(Pri2PdS)}}C5H3N]2 (4)
Conclusion
Pb(1)-C(6)
Pb(1)-C(25)
Pb(1)-N(1)
Pb(1)-S(3)
Pb(2)-C(6)
Pb(2)-C(25)
2.471(7)
2.408(6)
2.538(5)
3.082(2)
2.408(6)
2.415(7)
Pb(2)-N(2)
Pb(2)-S(1)
P(1)-S(1)
P(2)-S(2)
P(3)-S(3)
P(4)-S(4)
2.556(5)
3.017(2)
2.002(3)
1.949(3)
1.987(3)
1.946(3)
To summarize, the monolithium salt prepared from
[(SdPPri2CH2)2C5H3N-2,6] acts as a ligand transfer reagent
in the synthesis of various heavier group 14 metal com-
pounds. Novel compound, including a digermylgermylene
and a tin(II) trichlorostannate, were synthesized and struc-
turally characterized by X-ray crystallography and spectro-
scopic methods.
C(25)-Pb(1)-C(6)
C(25)-Pb(1)-N(1)
C(6)-Pb(1)-N(1)
C(25)-Pb(1)-S(3)
C(6)-Pb(1)-S(3)
C(6)-Pb(2)-C(25)
88.8(2)
89.6(2)
55.5(2)
65.1(2)
111.7(2)
90.1(2)
C(6)-Pb(2)-N(2)
C(25)-Pb(2)-N(2)
C(6)-Pb(2)-S(1)
C(25)-Pb(2)-S(1)
Pb(2)-C(6)-Pb(1)
Pb(1)-C(25)-Pb(2)
91.9(2)
55.9(2)
66.5(2)
113.6(2)
88.2(2)
89.5(2)
Experimental Section
General Procedures. All manipulations were carried out under
an inert atmosphere of dinitrogen gas by standard Schlenk
techniques. Solvents were dried over and distilled from CaH2
(hexane) and/or Na (Et2O, toluene, and THF). Sn{N(SiMe3)2}2
and Pb{N(SiMe3)2}2 were prepared according to the litera-
ture procedures.29 2,6-Lutidine, diisopropylphosphine, sulfur,
Ge[GeCl2{(SdPPri2CH)(SdPPri2CH2)C5H3N-2,6}]2 (5)
Ge(1)-Ge(2)
Ge(1)-Ge(3)
Ge(1)-S(1)
Ge(2)-C(6)
Ge(2)-Cl(1)
Ge(2)-Cl(2)
Ge(3)-C(25)
2.478(6)
2.481(6)
2.675(1)
2.006(4)
2.189(1)
2.192(1)
2.004(4)
Ge(3)-Cl(3)
Ge(3)-Cl(4)
S(1)-P(1)
S(2)-P(2)
S(3)-P(3)
S(4)-P(4)
2.190(1)
2.193(1)
2.012(2)
1.951(2)
2.000(1)
1.956(1)
nBuLi in 1.6 M hexane, GeCl2 (dioxane), and SnCl2 were
3
purchased from Aldrich Chemical Co. and used without further
purification. The 1H, 13C{1H}, 31P{1H}, 119Sn{1H}, and 207Pb-
{1H} NMR spectra were recorded on Bruker WM-300 or Varian
400 spectrometers. The NMR spectra were recorded in THF-d8,
and the chemical shifts δ are relative to SiMe4 for 1H and
13C{1H} and 85% H3PO4, SnMe4, and PbMe4 for 31P{1H},
19Sn{1H}, and 207Pb{1H}, respectively.
Ge(2)-Ge(1)-Ge(3)
Ge(2)-Ge(1)-S(1)
Ge(3)-Ge(1)-S(1)
C(6)-Ge(2)-Cl(1)
C(6)-Ge(2)-Cl(2)
Cl(1)-Ge(2)-Cl(2)
C(6)-Ge(2)-Ge(1)
Cl(1)-Ge(2)-Ge(1)
Cl(2)-Ge(2)-Ge(1)
89.4(2)
82.8(3)
86.4(3)
108.2(1)
98.7(1)
100.5(5)
115.4(1)
110.9(4)
121.4(3)
C(25)-Ge(3)-Cl(3)
C(25)-Ge(3)-Cl(4)
Cl(3)-Ge(3)-Cl(4)
C(25)-Ge(3)-Ge(1)
Cl(3)-Ge(3)-Ge(1)
Cl(4)-Ge(3)-Ge(1)
P(1)-S(1)-Ge(1)
107.8(1)
99.8(1)
99.4(5)
119.0(1)
108.8(4)
119.9(4)
109.3(5)
111.4(2)
112.1(2)
[(SdPPri2CH2)2C5H3N-2,6] (1). A solution of the dipho-
sphine [(PPri2CH2)2C5H3N-2,6] (8.60 g, 25.3 mmol) in toluene
(20 mL) was added slowly to a solution of sulfur (1.62 g,
50.6 mmol) in toluene (20 mL) at room temperature. The
reaction mixture was stirred at 60 °C for 14 h, and a colorless
solution was formed. After filtration and concentration of
the filtrate, compound 1 was obtained as colorless crystals.
Yield: 9.11 g (89.2%). Mp: 127.8-130.1 °C. Anal. Found: C,
56.66; H, 8.89; N, 3.50. Calcd for C19H35NP2S2: C, 56.55; H,
8.74; N, 3.47. 1H NMR (THF-d8): δ 1.15-1.23 (m, 24H,
P(1)-C(6)-Ge(2)
P(3)-C(25)-Ge(3)
[{C5H3N-2,6-(CH2PPri2dS)(CHPPri2dS)}Snþ][SnCl3-] (6)
Sn(1)-N(1)
Sn(1)-C(6)
Sn(1)-S(1)
Sn(2)-Cl(1)
Sn(2)-Cl(2)
2.295(5)
2.529(7)
2.662(4)
2.495(4)
2.468(3)
Sn(2)-Cl(3)
S(1)-P(1)
S(2)-P(2)
P(1)-C(6)
P(2)-C(13)
2.519(4)
2.043(3)
2.003(3)
1.771(6)
1.836(7)
CHMe2), 2.17-2.35 (m, 4H, CHMe2), 3.36 (d, 4H, JP-H
13.2 Hz, CH2), 7.26 (d, 1H, JH-H = 6.9 Hz, Py), 7.37 (d, 1H,
H-H = 7.5 Hz, Py), 7.59 (t, 1H, JH-H = 7.8 Hz, Py). 13C{1H}
NMR (THF-d8): δ 16.3-18.6 (m, CHMe2), 27.4-30.3 (m,
=
J
N(1)-Sn(1)-C(6)
N(1)-Sn(1)-S(1)
C(6)-Sn(1)-S(1)
Cl(2)-Sn(2)-Cl(1)
Cl(2)-Sn(2)-Cl(3)
59.6(2)
90.2(1)
72.7(2)
95.5(1)
94.5(9)
Cl(1)-Sn(2)-Cl(3)
P(1)-S(1)-Sn(1)
C(6)-P(1)-S(1)
C(13)-P(2)-S(2)
94.9(9)
83.7(1)
107.5(2)
111.6(3)
CHMe2), 39.2 (d, JP-C = 150.3 Hz, CH2), 124.0 (d, JP-C
=
282.2 Hz, Py), 137.4, 155.0 (Py). 31P{1H} NMR (THF-d8):
δ 82.81.
[Li{(SdPPri2CH)(SdPPri2CH2)C5H3N-2,6}(Et2O)] (2). To
a solution of 1 (0.82 g, 2.03 mmol) in THF (30 mL) was added
nBuLi (1.20 mL, 1.92 mmol) slowly at 0 °C. The reaction mixture
was stirred at room temperature for 17 h, and a yellow solu-
tion was formed. Volatiles in the mixture were removed under
reduced pressure, and the residue was extracted with Et2O. After
filtration and concentration of the filtrate, compound 2 was
obtained as yellow crystals. Yield: 0.40 g (48.7%). Mp: 129.3-
130.5 °C. Anal. Found: C, 56.98; H, 9.24; N, 3.03. Calcd
trigonal pyramidal, while the anionic tin center displays a
trigonal-pyramidal structure. Both geometries imply a
stereochemically active lone pair at the tin centers. The
˚
Sn-C bond distance of 2.529(7) A in 6 is significantly longer
than that of 2.329(4) A in Sn[CPh(SiMe3)(C5H4N-2)]225 and
˚
26
˚
2.281(5) A in Sn[2,4,6-(F3C)3C6H2]2. The Sn-S bond
distance of 2.662(4) A is shorter than those of 2.838(7) and
˚
for C19H34LiNP2S2 Et2O: C, 57.12; H, 9.17; N, 2.90. 1H
2.914(7) A in Sn[OC(CF3)2CH2P(S) Bu2]2.27 The P(1)-C(6)
t
˚
3
NMR (THF-d8): δ 1.24-1.53 (m, 12H, CHMe2), 1.62-1.86
(m, 12H, CHMe2), 1.92-2.09 (m, 2H, CHMe2), 2.42-2.54 (m,
2H, CHMe2), 2.99 (d, 2H, JP-H = 13.2 Hz, CH2), 3.61 (d, 1H,
JP-H = 16.5 Hz, CH), 6.89 (d, 1H, JH-H = 8.7 Hz, Py), 7.12
(t, 1H, JH-H = 8.7 Hz, Py), 7.37 (d, 1H, JH-H = 7.5 Hz, Py).
13C{1H} NMR (THF-d8): δ 15.7-17.4 (m, CHMe2), 27.4-28.0
˚
bond distance of 1.771(6) A and P(1)-S(1) bond distance of
˚
2.043(3) A in 6 are different from those found in 3 (P-C =
˚
˚
1.835(2) A; P-S = 1.941(1) A), suggesting charge delocali-
zation within the C-P-S skeleton. The average Sn-Cl bond
(m, CHMe2), 31.3 (d, JP-C = 270.7 Hz, CH2), 65.6 (d, JP-C
182.0 Hz, CH), 125.2 (d, JP-C = 90.1 Hz, Py), 128.5 (d, JP-C
=
=
(25) Leung, W.-P.; Kwok, W.-H.; Weng, L.-H.; Law, L. T. C.; Zhou,
Z.-Y.; Mak, T. C. W. J. Chem. Soc., Dalton Trans. 1997, 4301.
150 Hz, Py), 129.1, 133.21, 137.8 (Py). 31P{1H} NMR (THF-d8):
δ 58.36, 71.29.
€
(26) Grutzmacher, H.; Pritzkow, H.; Edelmann, F. T. Organometal-
lics 1991, 10, 23.
(27) Ionkin, A. S.; Marshall, W. J.; Fish, B. M. Organometallics 2006,
25, 4170.
(28) Constantine, S. P.; De Lima, G. M.; Hitchcock, P. B.; Keates,
(29) Gynane, M. J. S.; Harris, D. H.; Lappert, M. F.; Power, P. P.;
ꢁ
ꢁ
J. M.; Lawless, G. A. Chem. Commun. 1996, 2337.
Riviere, P.; Riviere-Baudet, M. J. Chem. Soc., Dalton Trans. 1977, 2004.

Article
Organometallics, Vol. 29, No. 8, 2010 1895
Table 3. Crystallographic Data for Compounds 2-4
2
3
4
formula
fw
color
C23H44LiNOP2S2
483.59
yellow
C38H66Sn2N2P4S4 Et2O
3
C38H66Pb2N2P4S4 Et2O
3
1112.53
orange
1289.53
red
cryst syst
space group
orthorhombic
P212121
11.834(2)
14.601(3)
16.589(3)
90
monoclinic
C2/c
21.031(2)
15.0474(18)
16.758(2)
90
91.251(2)
90
5302.0(11)
4
1.394
triclinic
P1
ꢀ
˚
a (A)
10.533(3)
15.395(4)
16.602(4)
78.485(5)
85.666(5)
85.908(6)
2626.0(12)
2
ꢀ
˚
b (A)
ꢀ
˚
c (A)
R (deg)
β (deg)
90
90
γ (deg)
3
ꢀ
˚
V (A )
2866.4(10)
4
1.121
0.311
1048
Z
dcalcd (g cm-3
)
1.631
6.715
1272
μ (mm-1
F(000)
)
1.252
2288
cryst size (mm)
2θ range (deg)
index ranges
0.50 ꢀ 0.50 ꢀ 0.30
2.11-25.00
0 e h e 14
0 e k e 17
0 e l e 19
2852
0.50 ꢀ 0.50 ꢀ 0.40
1.66-28.32
-28 e h e 19
-18 e k e 20
-22 e l e 22
18 286
1.50 ꢀ 0.50 ꢀ 0.30
1.35-25.00
-12 e h e 12
-11 e k e 18
-19 e l e 19
14 225
no. of rflns collected
no. of indep rflns
2852
6568
9222
R1, wR2 (I > 2σ(I))
R1, wR2 (all data)
goodness of fit, F2
0.0605, 0.1585
0.1310, 0.1942
0.980
0.0244, 0.0618
0.0344, 0.0689
1.020
0.0428, 0.1113
0.0561, 0.1198
1.027
no. of data/restraints/params
2852/4/271
0.298 to -0.284
6568/0/249
0.507 to -0.406
9222/0/496
2.329 to -3.121
-3
ꢀ
˚
largest diff peaks, e A
[{2-{Sn{C(Pri2PdS)}}-6-{CH2(Pri2PdS)}}C5H3N]2 (3). A
solution of Sn{N(SiMe3)2}2 (1.10 g, 2.50 mmol) in toluene
(10 mL) was added to a solution of 1 (1.01 g, 2.50 mmol) in
toluene (10 mL) at room temperature. The reaction mixture
was stirred at room temperature for 2 days, and an orange
solution was formed. Volatiles in the mixture were removed
under reduced pressure, and the residue was extracted with
Et2O. After filtration and concentration of the filtrate, com-
pound 3 was obtained as orange crystals. Yield: 1.57 g (60.4%).
Mp: 110.5-112.1 °C. Anal. Found: C, 43.29; H, 6.45; N, 2.65.
Calcd for C38H66Sn2N2P4S4: C, 43.86; H, 6.39; N, 2.69. 1H
NMR (THF-d8): δ 1.10-1.66 (m, 48H, CHMe2), 2.20-2.43 (m,
8H, CHMe2), 3.39 (d, 4H, JP-H = 21.2 Hz, CH2), 6.68 (d, 2H,
Table 4. Crystallographic Data for Compounds 5 and 6
5
6
formula
fw
color
cryst syst
space group
C38H68Ge3Cl4N2P4S4 C19H34Sn2Cl3NP2S2
1164.63
746.6
yellow
colorless
triclinic
P1
monoclinic
P21/c
ꢀ
˚
a (A)
b (A)
9.0484(12)
13.2864(18)
22.754(3)
95.876(3)
92.024(3)
93.584(3)
2713.5(6)
2
28.75(4)
7.821(11)
28.33(4)
90
109.53(3)
90
6005(15)
8
1.651
2.184
2944
ꢀ
˚
ꢀ
˚
c (A)
R (deg)
β (deg)
γ (deg)
3
V (A )
ꢀ
˚
JH-H = 1.8 Hz, Py), 7.11 (t, 2H, JH-H = 1.5 Hz, Py), 7.30 (d,
2H, JH-H = 1.5 Hz, Py). 13C{1H} NMR (THF-d8): δ 16.1-17.5
(m, CHMe2), 26.2-29.8 (m, CHMe2), 38.9 (d, JP-C = 129 Hz,
CH2), 124.6 (d, JP-C = 142.4 Hz, Py), 130.3 (d, JP-C = 77.8 Hz,
Py), 137.2, 157.1, 162.2 (Py). 31P{1H} NMR (THF-d8): δ 69.70,
84.29 with satellites (J = 1221 Hz). 119Sn{1H} NMR (THF-d8):
δ -4.02.
Z
dcalcd (g cm-3
)
1.425
2.148
1196
μ (mm-1
F(000)
)
cryst size (mm)
2θ range (deg)
index ranges
0.50 ꢀ 0.30 ꢀ 0.20
0.90-28.05
-11 e h e 11
-17 e k e 12
-29 e l e 30
18 630
0.50 ꢀ 0.40 ꢀ 0.30
0.75-25.00
-34 e h e 31
-9 e k e 9
-28 e l e 33
29 245
[{2-{Pb{C(Pri2PdS)}}-6-{CH2(Pri2PdS)}}C5H3N]2 (4). A
solution of Pb{N(SiMe3)2}2 (1.75 g, 3.32 mmol) in toluene
(10 mL) was added to a solution of 1 (1.33 g, 3.32 mmol) in
toluene (10 mL) at room temperature. The reaction mixture
was stirred at room temperature for 2 days, and a red solution
was formed. Volatiles in the mixture were removed under
reduced pressure, and the residue was extracted with Et2O.
After filtration and concentration of the filtrate, compound 4
was obtained as red crystals. Yield: 1.44 g (35.7%). Mp:
231.5-234.2 °C. Anal. Found: C, 38.12; H, 5.68; N, 2.05. Calcd
no. of rflns collected
no. of indep rflns
R1, wR2 (I > 2σ(I))
R1, wR2 (all data)
goodness of fit, F2
no. of data/restraints/
params
12 890
10 476
0.0460, 0.1062
0.0866, 0.1280
1.023
0.0434, 0.0992
0.0805, 0.1191
0.992
2852/4/271
10 476/0/523
-3
ꢀ
˚
largest diff peaks, e A
0.298 to -0.284
2.296 to -0.663
1
for C38H66Pb2N2P4S4 1/2THF: C, 38.34; H, 5.59; N, 2.24. H
3
NMR (THF-d8): δ 0.88-1.34 (m, 48H, CHMe2), 1.98-2.29
(m, 8H, CHMe2), 3.35 (d, 4H, JP-H = 12.0 Hz, CH2), 6.21 (d,
2H, JH-H = 0.9 Hz, Py), 7.19 (t, 2H, JH-H = 1.2 Hz, Py), 7.34
(d, 2H, JH-H = 0.9 Hz, Py). 13C{1H} NMR (CH2Cl2-d2):
δ 16.5-17.4 (m, CHMe2), 26.1-28.5 (m, CHMe2), 38.3 (d,
JP-C = 90.3 Hz, CH2), 68.1 (d, JP-C = 113.2 Hz, C-Pb)
115.4 (d, JP-C = 66.8 Hz, Py), 124.3 (d, JP-C = 75.8 Hz, Py),
136.6, 147.8, 162.4 (Py). 31P{1H} NMR (THF-d8): δ 65.16, 73.30
with satellites (J = 1880 Hz). 207Pb{1H} NMR (THF-d8): δ
2193.42.
Ge[GeCl2{(SdPPri2CH)(SdPPri2CH2)C5H3N-2,6}]2 (5). A
solution of 2 (0.93 g, 1.93 mmol) in Et2O (20 mL) was added
to a solution of GeCl2 (dioxane) (0.67 g, 2.90 mmol) in Et2O
3
(20 mL) at 0 °C. The reaction mixture was stirred at room
temperature for 28 h, and a white suspension was formed. Volatiles
in the mixture were removed under reduced pressure, and the
residue was extracted with CH2Cl2. After filtration and concentra-
tion of the filtrate, compound 5 was obtained as colorless crystals.
Yield: 0.18 g (18.4%). Mp: 185.3-188.8 °C. Anal. Found: C,
38.88; H, 5.79; N, 2.35. Calcd for C38H68Ge3Cl4N2P4S4: C, 39.18;

1896 Organometallics, Vol. 29, No. 8, 2010
Leung et al.
H, 5.88; N, 2.40. 1H NMR (THF-d8): δ 1.05-1.33 (m, 48H,
CHMe2), 2.31-2.39 (m, 8H, CHMe2), 3.63 (d, 2H, JP-H = 3.3
δ 14.8-17.6 (m, CHMe2), 28.5-31.9 (m, CHMe2), 37.7 (d, JP-C
= 147.2 Hz, CH2), 63.8 (m, CH-Sn) 123.3 (d, JP-C = 240.8 Hz,
Py), 128.0 (d, JP-C = 180.8 Hz, Py), 137.0, 154.9, 161.9 (Py).
31P{1H} NMR (THF-d8): δ 81.37, 83.82. 119Sn{1H} NMR
(THF-d8): δ -119.94 (d, JSn-P = 140.3 Hz), -97.50.
Hz, CH), 3.68 (d, 4H, JP-H = 2.4 Hz, CH2), 7.26 (d, 2H, JH-H
1.2 Hz, Py), 7.36 (d, 2H, JH-H = 1.2 Hz, Py), 7.92 (t, 2H, JH-H
=
=
0.9 Hz, Py). 13C{1H} NMR (THF-d8): δ 16.5-17.4 (m, CHMe2),
26.1-28.5 (m, CHMe2), 37.9 (d, JP-C = 150.5 Hz, CH2), 45.2 (d,
JP-C = 90.2 Hz CH-Ge), 123.3 (d, JP-C = 65.8 Hz, Py), 125.3 (d,
JP-C = 80.2 Hz, Py), 136.3, 138.4, 155.7 (Py). 31P{1H} NMR
(THF-d8): δ 78.92, 84.28.
X-ray Crystallography. Single crystals were sealed in Linde-
mann glass capillaries under nitrogen. X-ray data of 2-6 were
collected on a Rigaku R-AXIS II imaging plate using graphite-
ꢀ
˚
monochromated Mo KR radiation (I = 0.710 73 A) from a
rotating-anode generator operating at 50 kV and 90 mA. Crystal
data are summarized in Tables 3 and 4. The structures were
solved by direct phase determination using the computer pro-
gram SHELXTL-PC30 on a PC 486 and refined by full-matrix
least squares with anisotropic thermal parameters for the non-
hydrogen atoms. Hydrogen atoms were introduced in their
idealized positions and included in structure factor calculations
with assigned isotropic temperature factor calculations. Full
details of the crystallographic analysis of 2-6 are given in the
Supporting Information.
[{C5H3N-2,6-(CH2PPri2dS)(CHPPri2dS)}Snþ][SnCl3-] (6).
A solution of 2 (1.32 g, 2.73 mmol) in Et2O (20 mL) was added to
a solution of SnCl2 (2.71 g, 14.30 mmol) in Et2O (20 mL) at 0 °C.
The reaction mixture was stirred at room temperature for 33 h,
and a yellow suspension was formed. Volatiles in the mixture
were removed under reduced pressure, and the residue was
extracted with CH2Cl2. After filtration and concentration of
the filtrate, compound 6 was obtained as yellow crystals. Yield:
1.53 g (75.1%). Mp: 153.5-157.2 °C. Anal. Found: C, 30.39; H,
4.75; N, 1.93. Calcd for C19H34Sn2Cl3NP2S2: C, 30.58; H, 4.59;
1
N, 1.88. H NMR (THF-d8): δ 0.88-1.26 (m, 24H, CHMe2),
2.10-2.22 (m, 2H, CHMe2), 2.52-2.69 (m, 2H, CHMe2), 3.13
(d, 1H, JP-H = 3 Hz, CH), 3.45 (d, 2H, JP-H = 12 Hz, CH2),
6.85 (d, 1H, JH-H = 0.9 Hz, Py), 7.01 (d, 1H, JH-H = 0.6 Hz,
Py), 7.56 (t, 1H, JH-H = 0.9 Hz, Py). 13C{1H} NMR (THF-d8):
Acknowledgment. This work was supported by The
Chinese University of Hong Kong Direct Grant
(Project Code 2060379).
Supporting Information Available: CIF files giving details
about the X-ray crystal structures for 2-6. This material is
available free of charge via the Internet at http://pubs.acs.org.
(30) Sheldrick, G. M. In Crystallographic Computing 3: Data Collec-
tion, Structure Determination, Proteins, and Databases; Sheldrick, G. M.,
Kruger, C., Goddard, R., Eds.; Oxford University Press: New York, 1985; p 175.