Synthesis, structures, and coordinating properties of phosphole-containing hybrid calixpyrroles

Article abstract of DOI:10.1021/om800099h

Symmetrie and asymmetric hybrid calixpyrroles containing a σ⁴-phosphole or σ⁴-2,3-dihydrophosphole unit (symmetric and asymmetric (σ⁴-P,N₂,X-hybrids: X = S, O) were prepared by using acid-promoted condensation reactions of the corresponding σ⁴-phosphatripyrranes with 2,5-bis(1-hydroxy-1- methylethyl)heteroles. The X-ray crystallographic analyses of the symmetric and asymmetric σ⁴-P,N₂,X-hybrids show that the cavity sizes of the σ⁴-P,N₂,S-hybrids are larger than those of the σ⁴-P,N₂,O-hybrids, mainly reflecting the difference in edge-to-edge distances of the thiophene and furan rings. The symmetric σ⁴-P,N₂,X-hybrids and the asymmetric σ⁴-P,N₂,S-hybrid were successfully converted to the corresponding σ³ forms by reductive desulfurization at the phosphorus center. Each of the symmetric σ³-P,N ₂,X-hybrids was obtained as a mixture of two conformers, where the lone pair of the phosphorus atom is located inside (in) and outside (out) the cavity. The interconversion between the in and out type conformers of die asymmetric σ³-P,N₂,S-hybrid was sufficiently slow to isolate each of them. The complexation reactions of the symmetric σ³-P,N₂,S-hybrid with Au(I), Pt(II), and Pd(II) ions afforded both of the in and out type complexes, where the in type complexes were the diermodynamically favored products. In the complexation reactions of the asymmetric σ³-P,N₂,S-hybrids, the stereochemistry at the phosphorus center was retained to give the in or out type complex exclusively. In the in-in type trans-M(II)-bis(phosphine) complexes (M = Pt, Pd) derived from the symmetric and asymmetric σ³-P,N ₂,S-hybrids, the M-Cl fragment is bound above the cavities of the two macrocycles. The crystal structures and the ¹H NMR spectra of these M(II) complexes reveal that the P,N₂,S-hybrid calixpyrroles bind the M-Cl fragments through P-M coordination and cooperative NH-Cl hydrogen-bonding interactions.

Full text of DOI:10.1021/om800099h

3142
Organometallics 2008, 27, 3142–3152
Synthesis, Structures, and Coordinating Properties of
Phosphole-Containing Hybrid Calixpyrroles
Takashi Nakabuchi,† Yoshihiro Matano,*,† and Hiroshi Imahori†,‡,§
Department of Molecular Engineering, Graduate School of Engineering, Kyoto UniVersity, Nishikyo-ku,
Kyoto 615-8510, Japan, Institute for Integrated Cell-Material Sciences, Kyoto UniVersity, Nishikyo-ku,
Kyoto 615-8510, Japan, and Fukui Institute for Fundamental Chemistry, Kyoto UniVersity, 34-4,
Takano-Nishihiraki-cho, Sakyo-ku, Kyoto 606-8103, Japan
ReceiVed February 4, 2008
Symmetric and asymmetric hybrid calixpyrroles containing a σ4-phosphole or σ4-2,3-dihydrophosphole
unit (symmetric and asymmetric σ4-P,N2,X-hybrids: X ) S, O) were prepared by using acid-promoted
condensation reactions of the corresponding σ4-phosphatripyrranes with 2,5-bis(1-hydroxy-1-methyleth-
yl)heteroles. The X-ray crystallographic analyses of the symmetric and asymmetric σ4-P,N2,X-hybrids
show that the cavity sizes of the σ4-P,N2,S-hybrids are larger than those of the σ4-P,N2,O-hybrids, mainly
reflecting the difference in edge-to-edge distances of the thiophene and furan rings. The symmetric σ4-
P,N2,X-hybrids and the asymmetric σ4-P,N2,S-hybrid were successfully converted to the corresponding
σ3 forms by reductive desulfurization at the phosphorus center. Each of the symmetric σ3-P,N2,X-hybrids
was obtained as a mixture of two conformers, where the lone pair of the phosphorus atom is located
inside (in) and outside (out) the cavity. The interconversion between the in and out type conformers of
the asymmetric σ3-P,N2,S-hybrid was sufficiently slow to isolate each of them. The complexation reactions
of the symmetric σ3-P,N2,S-hybrid with Au(I), Pt(II), and Pd(II) ions afforded both of the in and out type
complexes, where the in type complexes were the thermodynamically favored products. In the complexation
reactions of the asymmetric σ3-P,N2,S-hybrids, the stereochemistry at the phosphorus center was retained
to give the in or out type complex exclusively. In the in-in type trans-M(II)-bis(phosphine) complexes
(M ) Pt, Pd) derived from the symmetric and asymmetric σ3-P,N2,S-hybrids, the M-Cl fragment is
1
bound above the cavities of the two macrocycles. The crystal structures and the H NMR spectra of
these M(II) complexes reveal that the P,N2,S-hybrid calixpyrroles bind the M-Cl fragments through
P-M coordination and cooperative NH-Cl hydrogen-bonding interactions.
species by utilizing the pyrrole-NH groups as the multiple
hydrogen-bonding donors, while Floriani and co-workers ex-
tensively studied the coordination chemistry of calix[4]pyrroles,
in which these macrocycles had been used as fully deprotonated,
tetraanionic N4 ligands for various metals.5 Inspired by these
pioneering studies, many research groups have designed and
Introduction
Calix[4]pyrroles,1,2 which are regarded as the pyrrole ana-
logue of calix[4]arenes, have attracted growing interest in
supramolecular chemistry, since the discovery by Sessler and
co-workers that these macrocycles can bind anionic3 and neutral4
* To whom correspondence should be addressed. E-mail: matano@
scl.kyoto-u.ac.jp. Tel: +81-75-383-2567. Fax: +81-75-383-2571.
† Department of Molecular Engineering.
(4) Allen, W. E.; Gale, P. A.; Brown, C. T.; Lynch, V. M.; Sessler,
J. L. J. Am. Chem. Soc. 1996, 118, 12471.
(5) For example, see: (a) Jacoby, D.; Floriani, C.; Chiesi-Villa, A.;
Rizzoli, C. J. Chem. Soc., Chem. Commun. 1991, 220. (b) Jacoby, D.;
Floriani, C.; Chiesi-Villa, A.; Rizzoli, C. J. Chem. Soc., Chem. Commun.
1991, 790. (c) Jubb, J.; Floriani, C.; Chiesi-Villa, A.; Rizzoli, C. J. Am.
Chem. Soc. 1992, 114, 6571. (d) Jacoby, D.; Floriani, C.; Chiesi-Villa, A.;
Rizzoli, C. J. Am. Chem. Soc. 1993, 115, 7025. (e) Kretz, C. M.; Gallo, E.;
Solari, E.; Floriani, C.; Chiesi-Villa, A.; Rizzoli, C. J. Am. Chem. Soc. 1994,
116, 10775. (f) Piarulli, U.; Solari, E.; Floriani, C.; Chiesi-Villa, A.; Rizzoli,
C. J. Am. Chem. Soc. 1996, 118, 3634. (g) Floriani, C.; Solari, E.; Solari,
G.; Chiesi-Villa, A.; Rizzoli, C. Angew. Chem., Int. Ed. 1998, 37, 2245.
(h) Bonomo, L.; Solari, E.; Floriani, C.; Chiesi-Villa, A.; Rizzoli, C. J. Am.
Chem. Soc. 1998, 120, 12972. (i) Bonomo, L.; Dandin, O.; Solari, E.;
Floriani, C.; Scopelliti, R. Angew. Chem., Int. Ed. 1999, 38, 913. (j) Bonomo,
L.; Solari, E.; Latronico, M.; Scopelliti, R.; Floriani, C. Chem.-Eur. J.
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‡ Institute for Integrated Cell-Material Sciences.
§ Fukui Institute for Fundamental Chemistry.
(1) Baeyer, A. Ber. Dtsch. Chem. Ges. 1886, 19, 2184.
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San Diego, CA, 2000; Vol. 3, pp 385-403. (c) Sessler, J. L.; Gale, P. A.
In The Porphyrin Handbook; Kadish, K. M., Smith, K. M., Guilard, R.,
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P. A.; Anzenbacher, P., Jr.; Sessler, J. L. Coord. Chem. ReV. 2001, 222,
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(6) (a) Arumugam, N.; Jang, Y.-S.; Lee, C.-H. Org. Lett. 2000, 2, 3115.
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10.1021/om800099h CCC: $40.75
2008 American Chemical Society
Publication on Web 05/28/2008

Phosphole-Containing Hybrid Calixpyrroles
Organometallics, Vol. 27, No. 13, 2008 3143
Chart 1. Structures of Phosphole-Containing Hybrid
Calixpyrroles 1S and 2S
Figure 1. Schematic views of metal complexes of the phosphole-
containing hybrid calixpyrroles (a) and P(III)-functionalized
calix[4]arenes (b, c).
has already been studied by several groups. For example, Matt
and co-workers used an upper-rim bis(phosphine)-functionalized
calix[4]arene as a bidentate P ligand for Pt(II), Pd(II), and Ru(II)
complexes, in which the M-R fragments were entrapped inside
the macrocyclic cavity through trans-P-M-P chelation (Figure
1b).14d The phosphole-containing hybrid calixpyrroles are dis-
tinct from the P(III)-functionalized calix[4]arenes in three
aspects. First, as seen in the supramolecular chemistry of the
parent calix[4]pyrroles, the macrocyclic platform of the phos-
phole-containing hybrid calixpyrroles provides multiple hydrogen-
bonding sites for negatively charged groups. Second, the size,
shape, and binding ability of the hybrid platform are tunable
by altering the combination of the heterole components (e.g.,
X in Figure 1a). Finally, the rigidity of the phosphole unit allows
the coordinated metal to be located above the cavity without
chelation, which is difficult for the mono-P(III)-functionalized
calix[4]arenes owing to the C(calix)-P bond rotation (Figure
1c).14g,h
prepared a wide variety of hybrid calixpyrroles containing
nonpyrrolic arene units such as furan,6 thiophene,6c–f pyridine,7,8
and benzene8 to modify the binding ability of the calixpyrrole
platform. To our knowledge, however, no attempt has been made
to incorporate phosphole into the calixpyrrole platform,9–11
despite its utility as neutral P ligand for transition metals.12 We
expected that phosphole-containing hybrid calixpyrroles, for-
mally obtained by incorporating a phosphole unit into the
macrocyclic framework of the calixpyrrole, would exhibit some
promising features as the structurally well-defined macrocyclic
P ligands while keeping the hosting function (Figure 1a).
The coordination chemistry of the calix[4]arene derivatives
bearing P(III) functionalities13 at the upper14 or lower rims15
(7) (a) Jacoby, D.; Isoz, S.; Floriani, C.; Chiesi-Villa, A.; Rizzoli, C.
J. Am. Chem. Soc. 1995, 117, 2793. (b) Kra´l, V.; Gale, P. A.; Anzenbacher,
P., Jr.; Jurs´ıkova´, K.; Lynch, V.; Sessler, J. L. Chem. Commun. 1998, 9.
(8) Sessler, J. L.; Cho, W,-S.; Lynch, V.; Kra´l, V. Chem.-Eur. J. 2002,
8, 1134.
Here we report the synthesis, structures, and coordination
behavior of the hybrid calixpyrroles 1S and 2S (Chart 1), which
contain a phosphole unit and a 2,3-dihydrophosphole unit,
respectively, as one of the heterocyclic components. The
structures and thermal stabilities of the Au(I), Pt(II), and Pd(II)
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Matano, Y.; Miyajima, T.; Nakabuchi, T.; Imahori, H.; Ochi, N.; Sakaki,
S. J. Am. Chem. Soc. 2006, 128, 11760. (b) Matano, Y.; Nakabuchi, T.;
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Fukugaki, T.; Murai, K.; Orr, G. W.; Atwood, J. L. J. Inclusion Phenom.
1991, 10, 57. (b) Ozegowski, S.; Costisella, B.; Gloede, J. Phosphorous,
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(11) Mathey and co-workers prepared some phosphole-containing
macrocycles: (a) Mathey, F.; Mercier, F.; Nief, F.; Fischer, J.; Mitschler,
A. J. Am. Chem. Soc. 1982, 104, 2077. (b) Laporte, F.; Mercier, F.; Ricard,
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W. R.; Priermeier, T.; Herdtweck, E. J. Organomet. Chem. 1994, 481, 253.
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165, 93.

3144 Organometallics, Vol. 27, No. 13, 2008
Scheme 1. Synthesis of the σ4-P,N2,S- and σ4-P,N2,O-Hybrids
Nakabuchi et al.
complexes are also reported.16 As expected, 1S and 2S have
proven to behave as monodentate P ligands, whose macrocyclic
frameworks provide hydrogen-bond-donating NH groups to the
Pd-Cl and Pt-Cl fragments.
spectroscopic methods. In their mass spectra, parent ion peaks
were observed at m/z 610 (for 9S and 10S) and m/z 595 (for
9O and 10O), attributable to the 1:1 condensation products. In
the 31P NMR spectra of 9S, 9O, 10S, and 10O, only one peak
was observed at δ 69.6, 69.4, 62.3, and 63.1 ppm, respectively,
indicating that a single diastereomer had been isolated in each
Results and Discussion
1
reaction. In the H NMR spectra in CDCl3, the NH protons
Synthesis of Hybrid Calixpyrroles Containing σ4-Phosp-
hole or σ4-2,3-Dihydrophosphole Units. Scheme 1 outlines
the synthesis of calix[1]phosphole[1]thiophene[2]pyrroles and
calix[1]phosphole[1]furan[2]pyrroles (denoted hereafter as
P,N2,S- and P,N2,O-hybrids). Treatment of 2,5-bis(1-hydoroxy-
1-methylethyl)phosphole P-sulfide (3)17 with BF3 · OEt2 in
pyrrole, followed by column chromatography on silica gel, gave
an expected condensation product, 4, in 32% yield together with
unexpected products 5 and 6 in 26% and 27% yield, respec-
tively. Presumably, the nonaromatic character of the phosphole
ring allows the positive charge of carbenium intermediate 7 to
delocalize onto the ꢀ-carbons (eq 1).18,19 The structures of 4,
5, and 6 were characterized by standard spectroscopic tech-
appeared considerably downfield (δ 7.84-9.32 ppm) relative
to those of the σ3 type compounds 1S, 1O, and 2S (δ 6.4-7.57
ppm), implying that the hydrogen-bonding interaction was
present in solution (Vide infra).
Crystal Structures of σ4-Hybrids. Crystal structures of 9S,
9O, 10S, and 10O were elucidated by X-ray crystallography.
The ORTEP diagrams of 9S and 10S are shown in Figures 2
and 3, and those of 9O and 10O are shown in Figures S1 and
S2 (Supporting Information). The crystallographic parameters
are summarized in Table S1 (Supporting Information). In the
symmetric hybrids 9S and 9O, the pyrrole rings are connected
to the 2- and 5-positions of the phosphole ring through the
-CMe2- bridge. On the other hand, in the asymmetric hybrids
1
niques. Judging from the H and 31P NMR spectra, 5 and 6
were obtained as single diastereomers.20 The BF3-promoted
dehydrative condensation of 4 with 2,5-bis(1-hydroxy-1-meth-
ylethyl)thiophene (8S)6c,21 and 2,5-bis(1-hydroxy-1-methyleth-
yl)furan (8O)6c,21 gave symmetric σ4-P,N2,X-hybrids 9S (X )
S) and 9O (X ) O) in 61% and 39% yield, respectively. Similar
condensations of 5 with 8S and 8O afforded the corresponding
asymmetric σ4-P,N2,X-hybrids 10S and 10O in moderate yields.
Compounds 9S, 9O, 10S, and 10O were characterized by
(16) A preliminary communication was published in: Matano, Y.;
Nakabuchi, T.; Miyajima, T.; Imahori, H. Organometallics 2006, 25, 3105.
(17) Matano, Y.; Miyajima, T.; Nakabuchi, T.; Matsutani, Y.; Imahori,
H. J. Org. Chem. 2006, 71, 5792.
(18) Recently, Mathey and co-workers have reported that 2,5-bis(hy-
droxy(phenyl)methyl)phosphole P-sulfide reacts with a tripyrrane at one of
the phosphole-ꢀ-positions under Friedel-Crafts conditions to produce a
P-confused carbaporphyrinoid, which contains the 2,3-dihydro-3-pyrro-
lylphosphole subunit like 5 and 6. See ref 11e.
(19) When 6 was reacted with excess pyrrole for 5 h in the presence of
BF3 · OEt2, 5 was obtained as the main product (ca. 40%) with a substantial
recovery of unreacted 6 (ca. 40%). Therefore, 6 is a possible precursor
of 5.
(20) In the 1H NMR spectra, the NH protons of 5 and 6 appeared at the
relatively downfield region (δ 7.97-9.46 ppm) comparable to those of 10S
and 10O (δ 7.84-9.32 ppm), in which all the NH protons are hydrogen-
bonded to the PdS moiety of the phosphole ring (Vide infra). It is therefore
likely that the pyrrole groups and the sulfur atom in 5 and 6 are located on
the same side of the 2,3-dihydrophosphole ring, similar to those in 10S
and 10O.
Figure 2. ORTEP diagram of 9S (30% probability ellipsoids).
Except for NH, hydrogen atoms are omitted for clarity. Selected
bond lengths and distances (Å): S1-P, 1.9724(5); C1-C2, 1.344(2);
C2-C6, 1.485(2); C6-C7, 1.341(2); S1 · · · N1, 3.37; S1 · · · N2,
3.62.
(21) Chadwick, D. J.; Willbe, C. J. Chem. Soc., Perkin Trans. 1 1977,
887.

Phosphole-Containing Hybrid Calixpyrroles
Organometallics, Vol. 27, No. 13, 2008 3145
Table 2. Edge-to-edge Distances (Å) of 9S, 9O, 10S, and 10O
9S (X ) S) 90 (X ) O)
10S (X ) S) 10O (X ) O)
a
b
c
d
5.68
5.44
5.00
5.06
5.67
4.94
5.01
5.03
aa
b
3.97
5.40
5.02
5.02
3.96
4.91
5.05
5.06
ca
d
a Defined by the distances between the bridging carbon and the
ꢀ-carbon atom of the dihydrophosphole unit (indicated by “b”).
Figure 3. ORTEP diagram of 10S (50% probability ellipsoids).
Except for NH, hydrogen atoms are omitted for clarity. Selected
bond lengths and distances (Å): S1-P, 1.9772(14); C1-C2,
1.512(5); C1-C8, 1.334(5); C2-C6, 1.540(5); C6-C7, 1.337(4);
S1 · · · N1, 3.60; S1 · · · N2, 3.58.
Table 1. Dihedral Angles and N · · · S1 Distances
dihedral angles (deg)a
N · · · S1
distances (Å)
compound phosphole thiophene/furan
pyrrole
9S
9O
10S
10O
87.0
89.8
87.4
82.2
71.4
71.5
81.1
88.7
32.0, 56.2
32.5, 42.3
60.9, 62.9
44.3, 47.2
3.37, 3.62
3.34, 3.45
3.58, 3.60
3.58, 3.61
Figure 4. Variable-temperature 1H NMR spectra of 1S in toluene-
d8. Filled circles: major conformer; open circles: minor conformer.
a Dihedral angles between the heterole ring and the mean plane of the
four (three, in the case of 10S and 10O) bridging meso carbon atoms.
σ4-P,N2,S-hybrid 10S was examined. When heated with 2.8
equiv of P(NMe2)3 in refluxing toluene for 33 h, 9S was
completely consumed to afford the symmetric σ3-P,N2,S-hybrid
1S in 92% yield (eq 2). Similarly, 9O was converted to the
10S and 10O, one of the pyrrole rings is directly connected to
the 3-position of the 2,3-dihydrophosphole ring, producing two
chiral centers at the phosphorus and ꢀ-carbon atoms. The PdS
sulfur atom and the pyrrole rings are located on the same side,
suggesting that the stereochemistry of 5 was retained in the
condensation with 8S and 8O (Vide supra).
In the solid state, 9S, 10S, and 10O adopt a partial cone
conformation, whereas 9O adopts a cone conformation. All of
the hybrids possess a trapezoid-like cavity, where the PdS
moiety is located inside. The phosphole, 2,3-dihydrophosphole,
thiophene, and furan rings stand almost perpendicular to a plane
formed by the four (9S and 9O) or three (10S and 10O) bridging
meso carbon atoms, whereas the pyrrole rings are tilted
considerably to direct their NH groups toward the sulfur atom
of the PdS group (Table 1). The observed N · · · S1 distances
of 3.34-3.62 Å indicate that the hydrogen-bonding interaction
is present between the sulfur atom and the NH protons in 9S,
9O, 10S, and 10O.22
symmetric σ3-P,N2,O-hybrid 1O in 72% yield. The 1H and 31
P
NMR spectra indicate that each of 1S and 1O exists as a mixture
of two conformers, in which the lone pair of the phosphorus
atom is located inside and outside the cavity (1Xin and 1Xout in
1
eq 3; X ) S, O). That is, two sets of H resonances and two
31P peaks (δ 31.4 and 32.1 ppm for 1S; δ 32.3 and 37.6 ppm
for 1O) were observed at 25 °C in toluene-d8, whereas they
coalesced at 70 °C (Figure 4 for 1S; Figure S3 (Supporting
Information) for 1O). Unfortunately, 1Xin and 1Xout could not
be separated at 25 °C, suggesting that interconversion between
the two conformers takes place rapidly even at this temperature.
It is well known that a pyramidal inversion barrier for phosphole
(ca. 16 kcal mol-1) is smaller than those of the conventional
triorganylphosphines (30-35 kcal mol-1) due to the aromatic
stabilization at the planar transition state.23 The ratios of major/
minor conformers in 1S and 1O at 25 °C were determined to
be 4:1 and 5:1, respectively, based on the integral values.
As shown in Table 2, the cavity sizes of 9S and 10S are larger
than those of 9O and 10O, mainly reflecting the difference in
edge-to-edge distances b between the thiophene (9S: 5.44 Å
and 10S: 5.40 Å) and furan (9O: 4.94 Å and 10O: 4.91 Å)
subunits. These data clearly show that the cavity size of hybrid
calixpyrroles is tunable by simply changing the combination
of the heterole subunits.
In contrast to the desulfurization of the symmetric hybrids, a
large excess amount of P(NMe2)3 (130 equiv) and a longer
reaction time (60 h) were needed for the complete conversion
of the asymmetric σ4-P,N2,S-hybrid 10S to σ3-P,N2,S-hybrid
2S (eq 4), which was obtained as a mixture of two conformers
2Sin and 2Sout. However, the rate of interconversion between
2Sin and 2Sout is so slow at room temperature that both of them
could be isolated by column chromatography. The 31P NMR
spectra of 2Sin and 2Sout in CDCl3 showed only one peak at δ
Synthesis of σ3-Hybrids. In order to prepare the σ3 type
phosphole-containing calixpyrroles, reductive desulfurization of
the symmetric σ4-P,N2,X-hybrids 9S and 9O and asymmetric
(22) The N · · · S distances for the NH · · · S hydrogen bonds in silver-
antimony sulfides were reported to be 3.20-3.65 Å: Vaqueiro, P.;
Chippindale, A. M.; Cowley, A. R.; Powell, A. V. Inorg. Chem. 2003, 42,
7846.
(23) (a) Egan, W.; Tang, R.; Zon, G.; Mislow, K. J. Am. Chem. Soc.
1971, 93, 6205. (b) Deschamps, E.; Ricard, L.; Mathey, F. Angew. Chem.,
Int. Ed. Engl. 1994, 33, 1158. See also refs 11b,d.

3146 Organometallics, Vol. 27, No. 13, 2008
Nakabuchi et al.
1Sout and 1Oout are unlikely to bind DMSO-d6 at the core
because the phenyl and trimethylene groups would protect the
NH groups sterically (Figure 5b). This assignment was strongly
supported by the results on similar titration measurements for
the isolated asymmetric hybrids 2Sin and 2Sout. On addition of
DMSO-d6 (20 equiv), the NH peaks of 2Sin were shifted
downfield considerably [∆δ > 0.6 ppm] (Figure S4c), while
2Sout displayed negligible spectral change (Figure S4d).
Synthesis of Au(I), Pt(II), and Pd(II) Complexes. With the
σ3-P,N2,S-hybrids 1S, 2Sin, and 2Sout in hand, we set out to
examine their coordination behavior toward Au(I), Pt(II), and
Pd(II) salts. As mentioned above, the symmetric hybrid 1S exists
as an equilibrium mixture of two conformers 1Sin and 1Sout at
room temperature. Hence, both in and out type coordination
modes are conceivable in the complexation reactions (Figure
6a; hereafter in and out are used to indicate the conformation
of the σ3-P,N2,S-hybrids in metal complexes: in indicates 1Sin
or 2Sin, and out indicates 1Sout or 2Sout). On the other hand,
when the isolated asymmetric hybrids 2Sin and 2Sout are used
as ligands, either in or out type coordination could be observed
(Figure 6b). The structures of the metal complexes formed are
summarized as simplified representations in Figure 7.
Figure 5. Schematic views of possible interactions of DMSO-d6
with (a) 1Xin and (b) 1Xout
.
29.5 and 17.7 ppm, respectively. The structures of these two
conformers were confirmed by X-ray crystallographic analyses
of their metal complexes (Vide infra).
As shown in Table 3, 1S (a mixture of 1Sin and 1Sout) reacted
with 1.1 equiv of AuCl(SMe2) in toluene to give a mixture of
the in type complex 11in and the out type complex 11out. In
solution, 11out was gradually converted to 11in, indicating that
11in is thermodynamically more stable than 11out. The conver-
sion from 11out to 11in in toluene was almost complete within
1 h at room temperature. In contrast, 2Sin and 2Sout reacted with
AuCl(SMe2) to afford the in type complex 12in (eq 5) and the
out type complex 12out (eq 6), respectively, with keeping the
initial configuration at the phosphorus center. There was no sign
of interconversion between 12in and 12out in CDCl3 even after
10 h at room temperature. The in and out conformations of 11in
and 12out were confirmed by X-ray crystallography (Vide infra).
To assign the structures of the major and minor conformers
1
in the symmetric hybrids 1X, we performed H NMR titration
measurements of 1X using dimethyl sulfoxide-d6 (DMSO-d6)
as a guest, which were originally reported by Sessler and co-
workers for evaluating the hydrogen-bonding ability of meso-
octamethylcalix[4]pyrrole. These authors concluded that the
observed downfield shift of the NH protons stems from the
multiple hydrogen-bonding interactions between the pyrrolic NH
groups and the S-oxo moiety of DMSO.4 The results of the
present system are summarized in Figure S4 (Supporting
Information). As the amount of DMSO-d6 increased, the NH
peaks due to the major conformer in 1X shifted downfield [∆δ
) 0.06 ppm (10 equiv), 0.11 ppm (20 equiv) for 1S;24 ∆δ )
0.09 ppm (10 equiv), 0.17 ppm (20 equiv) for 1O]. By contrast,
the addition of DMSO-d6 caused no appreciable spectral change
for the minor conformer. These observations suggest that the
The complexation of the symmetric σ3-P,N2,S-hybrid 1S with
0.5 equiv of PtCl2 yielded three types of trans-Pt(II)-bis(pho-
sphine) complexes, 13i-i, 13i-o, and 13o-o (Table 4), which are
denoted as in-in,16 in-out,16 and out-out type, respectively. In
refluxing toluene, the relative ratio of 13i-i/13i-o/13o-o changed
from 4:54:42 (after 45 min) to 9:70:21 (after 2 h) and finally
reached an equilibrium value of 90:10:∼025 (after 4 days).
Similarly, the complexation of 1S with PdCl2 afforded the in-
in type and in-out type complexes 14i-i and 14i-o in a ratio of
92:8.26 In this reaction, the out-out type complex 14o-o was not
observed during the reaction. The same equilibrium states were
attained by heating the isolated in type complexes 13i-i and 14i-i
in refluxing toluene (13i-i/13i-o/13o-o ) 90:10:∼0 after 4 days;
14i-i/14i-o/14o-o) 92:8:∼0 after 2 h). These results indicate that
major and minor conformers in toluene-d8 are 1Xin and 1Xout
,
respectively. Namely, 1Sin and 1Oin are likely to bind DMSO-
d6 through the cooperative hydrogen-bonding interaction be-
tween two NH protons and the SdO group (Figure 5a,) whereas
(24) When dimethyl formamide-d7 (DMF-d7) was used as a guest, a
similar downfield shift of the NH peaks was observed [∆δ ) 0.08 ppm (10
equiv), 0.15 ppm (20 equiv)]. On the other hand, addition of tetrabutylam-
monium fluoride (10 equiv) or tetrabutylammonium chloride (10 equiv) to
a solution of 1S (12 mM in toluene-d8 or CD2Cl2) did not cause appreciable
downfield shift of the NH peaks.
(25) The preference for the in mode coordination was also found in a
similar reaction in DMF (110 °C, 4 days: 13i-i/13i-o/13o-o ) 92/8/∼0).
(26) Owing to the poor solubility of PdCl2 in toluene, a large amount
(ca. 50%) of free ligand 1S remained intact after 45 min.

Phosphole-Containing Hybrid Calixpyrroles
Organometallics, Vol. 27, No. 13, 2008 3147
Figure 6. Coordination behavior of the symmetric hybrid 1S (a) and asymmetric hybrids 2Sin and 2Sout (b).
Figure 7. Simplified representations of the metal complexes.
Table 3. Reaction of 1S with AuCl(SMe2)
The X-ray diffraction analyses of 15i-i and 16i-i revealed that
the two macrocyclic ligands have the same stereochemistry
at the phosphorus and ꢀ-carbon atoms (Vide infra), although
the data of 15i-i are not at the publishable level. The observed
high diastereoselectivity represents that the asymmetric P,N2,S-
hybrid ligand 2Sin coordinated to the metal center discriminates
the chirality of the second asymmetric ligand completely.
reaction conditions
relative ratioa 11in/11out (yield/%b)
RT, 15 min
RT, 1 h
110 °C, 2 h
91:9 (80/-)
97:3 (86/-)
97:3 (84/-)
1
a Determined by H NMR spectra. b Isolated yield.
the thermodynamic stability of 13 and 14 decreases in the order
in-in > in-out . out-out. It should be noted that, at room
temperature, the interconversion among the in-in, in-out, and
out-out complexes in CDCl3 does not occur even after 10 h.
The 31P NMR spectra of 13i-i, 13i-o, and 13o-o displayed char-
acteristic peaks at δ 46.7 ppm (1JP-Pt ) 2476 Hz), δ 45.5 and
Crystal Structures of Au(I), Pt(II), and Pd(II) Complexes.
The crystal structures of the Au(I) complexes 11in (sym) and
12out (asym), the Pt(II) complexes 13i-i (sym) and 13i-o (sym),
and the Pd(II) complexes 14i-i (sym) and 16i-i (asym) were
successfully elucidated by X-ray crystallography (Figures 8-12,
and S5 (Supporting Information), Table S1). In the Au(I)
complexes 11in and 12out, the gold center adopts a linear
geometry with P-Au-Cl bond angles of 173.20(2)-176.24(2)°
(Figures 8 and 9). The Au-P and Au-Cl bond lengths
[2.2391(8) and 2.2892(8) Å] of 11in are close to the respective
values of 12out [2.2381(4) and 2.2871(4) Å] and those reported
for the Au(I)-phosphole complexes.28 In 11in, the Au-Cl moiety
is located above the cavity provided by the symmetric σ3-P,N2,S
macrocycle with a cone conformation. On the other hand, the
Au-Cl moiety in 12out is located outside the cavity provided
46.5 ppm (1JP-Pt ) 2400, 2560 Hz), and δ 45.7 ppm (1JP-Pt
)
2445 Hz), respectively. The observed 31P-195Pt coupling
constants of 2400-2560 Hz are indicative of trans geometry
of the two phosphine ligands for all complexes.27 In the 31P
NMR spectrum of the Pd(II) complex 14i-i, a single peak was
observed at δ 49.4 ppm. The structures of 13i-i, 13i-o, and 14i-i
were ultimately confirmed by X-ray crystallography (Vide infra).
Finally, the reactions of the asymmetric σ3-P,N2,S-hybrid 2Sin
with 0.5 equiv of MCl2 (M ) Pt, Pd) were examined (eq 7). In
both cases, the in-in type trans-M(II)-bis(phosphine) complexes
15i-i, (M ) Pt) and 16i-i (M ) Pd) were obtained as major
products in 83% and 79% yield, respectively. The 31P NMR
spectra of 15i-i and 16i-i showed only one resonance at δ 40.2
ppm (1JPt-P ) 2421 Hz) and δ 44.0 ppm, respectively, indicating
that 15i-i and 16i-i had been isolated as single diastereomers.
(27) (a) Rahn, J. A.; Baltusis, L.; Nelson, J. H. Inorg. Chem. 1990, 29,
750. (b) Power, W. P.; Wasylishen, R. E. Inorg. Chem. 1992, 31, 2176.

3148 Organometallics, Vol. 27, No. 13, 2008
Nakabuchi et al.
Table 4. Reaction of the Symmetric σ3-P,N2,S-Hybrid 1S with MCl2 (M ) Pt, Pd)
relative ratioa (yield/%b)
reaction time
13i-i/13i-o/13o-o
14i-i/14i-o/14o-o
45 min
2 h
4 days
4:54:42 (-:49:37)
9:70:21 (12:60:24)
90:10:∼0 (85:-:-)
92: 8:∼0 (45:-:-)c
92: 8:∼0 (88:-:-)
a Determined by 1H NMR spectra. b Isolated yields. c About 50% of free ligand 1S was recovered.
Figure 9. ORTEP diagram of 12out (30% probability ellipsoids).
Hydrogen atoms are omitted for clarity. Selected bond lengths (Å)
and angles (deg): Au-Cl, 2.2871(4); Au-P, 2.2381(4); C1-C2,
1.532(2); C1-C8, 1.343(3); C2-C6, 1.529(3); C6-C7, 1.343(3);
Cl-Au-P, 176.24(2).
Figure 8. ORTEP diagram of 11in (30% probability ellipsoids).
Hydrogen atoms are omitted for clarity. Selected bond lengths (Å)
and angles (deg): Au-Cl, 2.2892(8); Au-P, 2.2391(8); C1-C2,
1.343(4); C2-C6, 1.469(4); C6-C7, 1.347(4); Cl-Au-P,
173.20(2).
by the asymmetric σ3-P,N2,S macrocycle with a partial cone
conformation.
As shown in Figures 10-12 and S5, each metal center in
the Pt(II) complexes 13i-i and 13i-o and the Pd(II) complexes
14i-i and 16i-i has a square-planar geometry, and two phosphorus
atoms are coordinated in a trans orientation. The Pt-P and
Pt-Cl bond lengths in 13i-i [2.3390(14), 2.3286(14) Å and
2.3035(12), 2.2992(11) Å] and 13i-o [2.3218(6), 2.3375(5) Å
and 2.3195(5), 2.3018(6) Å] are close to the values reported
for a trans-Pt(II)-bis(2,5-dialkylphosphole) complex [2.309(3),
2.318(3) Å and 2.296(3), 2.301(3) Å].12g Similarly, the Pd-P
and Pd-Cl bond lengths of 14i-i [2.3496(8), 2.3548(8) Å and
2.2990(6), 2.3034(6) Å] and 16i-i [2.3488(10), 2.3343(8) Å and
2.2999(9), 2.3007(9) Å] are comparable to the values reported
for a trans-Pd(II)-bis(2,5-dialkylphosphole)complex [2.325(7),
2.353(7) Å and 2.271(7), 2.280(7) Å].12g
In the in-out type Pt(II) complex 13i-o, one of the symmetric
σ3-P,N2,S ligands adopts a 1,2-alternate conformation and binds
the platinum moiety outside the cavity, whereas the other adopts
a cone conformation and binds the platinum moiety above the
Figure 10. ORTEP diagram of 13i-i (30% probability ellipsoids).
meso-Me groups and hydrogen atoms except for NH are omitted
for clarity. Selected bond lengths (Å), angles (deg), and distances
(Å): Pt-Cl1, 2.3035(12); Pt-Cl2, 2.2992(11); Pt-P1, 2.3390(14);
Pt-P2, 2.3286(14); Cl1-Pt-P1, 94.76(4); Cl1-Pt-P2, 86.99(4);
Cl2-Pt-P1, 86.57(4); Cl2-Pt-P2, 93.36(4); Cl1 · · · N3, 3.27;
Cl1 · · · N4, 3.52; Cl2 · · · N1, 3.50; Cl2 · · · N2, 3.23.
(28) (a) Attar, S.; Bearden, W. H.; Alcock, N. W.; Alyea, E. C.;
Nelson, J. H. Inorg. Chem. 1990, 29, 425. Au-P, 2.220(9)-2.227(2) Å;
Au-Cl, 2.282(9)-2.288(2) Å. (b) Su, H.-C.; Fadhel, O.; Yang, C.-J.; Cho,
T.-Y.; Fave, C.; Hissler, M.; Wu, C.-C.; Re´au, R. J. Am. Chem. Soc. 2006,
128, 983. Au-P, 2.2290(16)-2.2300(16) Å; Au-Cl, 2.2638(18)-
2.2895(19) Å (c) Dienes, Y.; Eggenstein, M.; Neumann, T.; Englert, U.;
Baumgartner, T. Dalton Trans. 2006, 1424. Au-P, 2.2249(12) Å; Au-Cl,
2.2946(12) Å.
cavity. In the in-in type Pt(II) and Pd(II) complexes 13i-i and
14i-i, the conformation of two symmetric σ3-P,N2,S ligands is
basically the same as that of the in type ligand of 13i-o. In these
in-in type complexes, however, the whole structure has a C2h

Phosphole-Containing Hybrid Calixpyrroles
Organometallics, Vol. 27, No. 13, 2008 3149
sharp contrast, the crystal structures of the present complexes
11in, 13i-i, 13i-o, 14i-i, and 16i-i clearly show that the symmetric
and asymmetric σ3-P,N2,S-hybrids 1S and 2Sin behave as
monodentate P ligands to bind the metal above the cavity. This
is attributable to the difference in rigidity at the phosphorus
center between the monophosphinated calix[4]arenes and the
σ3-P,N2,S-hybrids: the latter ligands are much more rigid than
the former ones. Another interesting feature of the σ3-P,N2,S-
hybrid ligands stems from the pyrrole units, which behave as
hydrogen-bonding donors. In the 1H NMR spectra of the Pt(II)
and Pd(II) complexes 13i-i, 13i-o, 14i-i, 14i-o, 15i-i, and 16i-i in
CDCl3, the NH resonances of the in type ligands were observed
downfield relative to those of their free bases 1Sin and 2Sin (∆δ
) 1.2-2.7 ppm; Table 5). In fact, in the crystal structures, two
pyrrole rings of the in type macrocyclic ligands of 13i-i, 13i-o,
14i-i, and 16i-i are tilted to direct the NH protons toward the
chlorine atom bound to the metal with N · · · Cl distances of
3.18-3.52 Å, which are close to the reported values [3.264(7)-
3.331(7) Å] of a chloride ion complex of meso-octamethyl-
calix[4]pyrrole.3a These observations demonstrate the presence
of cooperative hydrogen-bonding interactions between the
M-Cl (M ) Pt, Pd) fragment and the NH protons in these
complexes.
Figure 11. ORTEP diagram of 13i-o (30% probability ellipsoids).
meso-Me groups and hydrogen atoms except for NH are omitted
for clarity. Selected bond lengths (Å), angles (deg), and distances
(Å): Pt-Cl1, 2.3194(6); Pt-Cl2, 2.3018(6); Pt-P1, 2.3219(6);
Pt-P2, 2.3375(6); Cl1-Pt-P1, 85.09 (2); Cl1-Pt-P2, 88.89(2);
Cl2-Pt-P1, 93.20(2); Cl2-Pt-P2, 93.08(2); Cl1 · · · N1, 3.41;
Cl1 · · · N2, 3.40.
Concluding Remarks
Symmetric and asymmetric hybrid calixpyrroles containing
a phosphole or a 2,3-dihydrophosphole unit (symmetric and
asymmetric P,N2,X-hybrids) were prepared for the first time via
acid-promoted condensation reactions of the σ4-phosphatripyr-
ranes with 2,5-difunctionalized heteroles. As clearly revealed
by X-ray crystallographic analyses of the σ4-P,N2,X-hybrids,
the cavity size of the phosphole-containing hybrid calixpyrroles
is tunable by exchanging the components of the macrocyclic
backbone. The results on the complexation of the symmetric
and asymmetric σ3-P,N2,S-hybrid calixpyrroles with Au(I),
Pd(II), and Pt(II) salts represent that both the symmetric and
asymmetric σ3-P,N2,S-hybrids behave as monodentate P ligands.
It is of particular interest that the pyrrole NH protons can be
utilized as hydrogen-bonding donors to the metal-bound chlorine
atoms. The present study demonstrates the potential utility of
the phosphole-containing hybrid calixpyrroles as a new class
of multifunctional macrocyclic P ligands.
Experimental Section
General Comments. All melting points are uncorrected. 1H,
13C{1H}, and 31P{1H} NMR spectra were recorded using CDCl3
as the solvent unless otherwise noted. Chemical shifts are reported
as the relative value versus tetramethylsilane (1H and 13C) and
H3PO4 (31P). MALDI-TOF and (HR-)FAB mass spectra were
measured using CHCA and 3-nitrobenzyl alcohol as matrixes.
CH2Cl2 and toluene were distilled from calcium hydride before use.
All the reactions were performed under an argon or nitrogen
atmosphere. Column chromatography was performed on silica gel
or on a fast flow liquid chromatography system fitted with a silica
gel column. Compound 3 was prepared by the reaction of the
corresponding 2,5-diester with excess MeMgBr.17 Other chemicals
were of reagent grade quality, purchased commercially, and used
without further purification unless otherwise noted. Although
spectroscopic data clearly supported high purity of all the isolated
compounds, we were not successful in obtaining satisfactory
analytical data for 2Sin, 2Sout, 6, 9O, 10O, 11in, 12in, 12out, 13i-o,
13o-o, 14i-i, 15i-i, and 16i-i with an accuracy of (0.4% probably due
to incorporation of solvent molecules in the solid state. The 1H
Figure 12. ORTEP diagram of 16i-i (30% probability ellipsoids).
meso-Me groups and hydrogen atoms except for NH are omitted
for clarity. Selected bond lengths (Å), angles (deg), and distances
(Å): Pd-Cl1, 2.2999(9); Pd-Cl2, 2.3007(9); Pd-P1, 2.3488(10);
Pd-P2, 2.3343(8); Cl1-Pd-P1, 89.13(3); Cl1-Pd-P2, 93.01(3);
Cl2-Pd-P1, 94.85(3); Cl2-Pd-P2, 86.04(3); Cl1 · · · N1, 3.38;
Cl1 · · · N2, 3.18; Cl2 · · · N3, 3.51; Cl2 · · · N4, 3.23.
symmetry, and the metal center is located above the cavities of
two macrocyclic ligands as though it is wrapped around. In the
in-in type Pd(II) complex 16i-i, two asymmetric σ3-P,N2,S
ligands coordinating to one palladium center have the same
stereochemistry and adopt partial cone conformations. The
coordination mode of 16i-i is similar to those of 13i-i and 14i-i.
Harvey and co-workers reported that the metal fragments of
Rh(III)complexesoftheupper-rimmonophosphinatedcalix[4]arenes
were located outside the cavity in the crystalline state.14g,h In

3150 Organometallics, Vol. 27, No. 13, 2008
Nakabuchi et al.
Table 5. N · · · Cl Distances and NH Resonances in the Pt(II) and Pd(II) Complexes
complex
N · · · Cl distances (Å)
NH resonances in CDCl3 (ppm)
∆δ (ppm)a
13i-i
13i-o
13o-o
14i-i
15i-i
16i-i
3.23, 3.27, 3.50, 3.52
3.40b, 3.41b
8.85
1.5-1.8
8.91b, 7.19c
7.22
1.5-1.8b, -0.2-0.1c
-0.2-0.1
3.26, 3.27, 3.49, 3.50
8.98
8.24, 9.34
8.37, 9.58
1.6-1.9
1.2-1.4, 2.3-2.5
1.3-1.5, 2.6-2.7
3.18, 3.23, 3.38, 3.51
a Differences in the NH resonances between the metal complexes (δ(M)) and the free ligands (δ(F)): ∆δ ) δ(M) - δ(F). b Values for the in type
ligands. c Values for the out type ligands.
1
NMR spectra of these compounds are included as Figures S6-S18
in the Supporting Information.
9S: Mp 241-242 °C; H NMR δ 1.27 (m, 1H), 1.32 (s, 6H),
1.36 (s, 6H), 1.65 (s, 6H), 1.72 (s, 6H), 1.86 (m, 1H), 2.10 (m,
4H), 5.79 (m, 4H), 6.78 (s, 2H), 7.50 (m, 3H), 7.90 (m, 2H), 9.09
(s, 2H); 13C{1H} NMR δ 26.7, 27.2, 28.0, 28.2, 31.4, 31.7, 37.4,
37.6, 38.1, 99.8, 101.7, 101.8, 123.6, 128.6, 129.1, 129.5, 131.8,
135.5, 136.5, 137.0, 141.3, 152.0, 158.4, 158.7; 31P{1H} NMR
(toluene-d8) δ 69.6; MS (FAB) m/z 610 (M+); Anal. Calcd for
C37H43N2PS2: C, 72.75; H, 7.10; N, 4.59; P, 5.07. Found: C, 72.85;
H, 7.10; N, 4.47; P, 5.12.
Synthesis of Compounds 4, 5, and 6. To a solution of diol 3
(2.2 g, 6.3 mmol) in 60 mL (870 mmol) of pyrrole was added 0.78
mL (6.3 mmol) of BF3 · OEt2. After stirring for 5 h at room
temperature, CH2Cl2 (50 mL) and saturated NaHCO3 solution (30
mL) were added. The water phase was extracted with CH2Cl2, and
the organic extracts were combined, washed with brine, dried over
Na2SO4, and evaporated. Purification by silica gel column chro-
matography (CH2Cl2/EtOAc ) 50:1) followed by recrystallization
from EtOAc/hexane afforded compounds 4 (890 mg, 32%; Rf )
0.6), 5 (740 mg, 26%; Rf ) 0.5), and 6 (670 mg, 27%; Rf ) 0.2)
as colorless solids.
4: Mp 154-155 °C; 1H NMR δ 1.38 (s, 6H), 1.41 (s, 6H),
1.54-1.62 (m, 1H), 1.90-1.94 (m, 1H), 2.09-2.25 (m, 4H),
5.88-5.90 (m, 2H), 5.99-6.01 (m, 2H), 6.70-6.71 (m, 2H),
7.48-7.59 (m, 3H), 7.97 (m, 2H), 9.12 (br s, 2H); 13C{1H} NMR
δ 26.6, 26.6, 27.6, 27.7, 27.9, 28.1, 28.7, 28.8, 37.7, 37.8, 102.5,
106.4, 117.2, 128.8, 129.8, 131.7, 131.8, 135.0, 136.1, 138.3, 138.3,
158.0, 158.4; 31P{1H} NMR δ 69.3; MS (MALDI-TOF) m/z 447
(M+). Anal. Calcd for C27H31N2PS: C, 72.61; H, 7.00; N, 6.27; P,
6.94. Found: C, 72.60; H, 6.99; N, 6.27; P, 6.89.
5: Mp 163-164 °C; 1H NMR δ 1.28 (s, 3H), 1.48 (s, 3H), 1.54
(d, 3H, J ) 2.4 Hz), 1.65-1.71 (m, 1H), 1.68 (d, 3H, J ) 2.0 Hz),
1.77-1.91 (m, 2H), 1.92-2.01 (m, 1H), 2.11-2.26 (m, 1H),
2.79-2.88 (m, 1H), 5.79-5.81 (m, 1H), 5.94-5.96 (m, 1H),
6.03-6.05 (m, 1H), 6.07-6.09 (m, 1H), 6.55-6.57 (m, 1H),
6.77-6.78 (m, 1H), 7-9 (br, 2H), 7.50-7.61 (m, 3H), 7.97 (br s,
1H), 9.60 (br s, 1H); 13C{1H} NMR δ 22.8, 22.9, 23.5, 23.5, 23.6,
23.8, 23.9, 27.6, 27.6, 30.1, 30.1, 34.6, 34.7, 38.2, 38.3, 60.0, 60.2,
102.8, 102.9, 104.8, 106.7, 106.9, 116.8, 118.5, 128.6, 131.5, 131.5,
132.3, 133.0, 133.1, 133.8, 134.1, 134.9, 139.8, 139.9, 147.5, 147.6,
168.6, 168.8; 31P{1H} NMR δ 62.2; MS (MALDI-TOF) m/z 447
(M+). Anal. Calcd for C27H31N2PS: C, 72.61; H, 7.00; N, 6.27.
Found: C, 72.47; H, 6.99; N, 6.26.
6: Mp 180-182 °C; 1H NMR δ 1.07 (s, 3H), 1.36 (s, 3H), 1.57
(d, 3H, J ) 2.1 Hz), 1.69 (d, 3H, J ) 1.5 Hz), 1.86-1.96 (m, 1H),
2.04-2.20 (m, 1H), 2.29-2.52 (m, 3H), 2.88-2.94 (m, 1H), 3.30
(s, 1H), 6.07-6.09 (m, 1H), 6.15-6.17 (m, 1H), 6.78-6.80 (m,
1H), 7.46-7.51 (m, 3H), 7.87-7.94 (m, 2H), 9.46 (br s, 1H);
13C{1H} NMR δ 22.6, 22.7, 23.7, 23.8, 23.9, 24.8, 24.9, 28.3, 33.1,
33.2, 34.4, 34.4, 60.6, 60.9, 72.8, 73.0, 104.8, 106.8, 118.8, 128.3,
128.5, 131.4, 131.4, 131.6, 131.8, 132.2, 133.1, 133.2, 133.2, 133.9,
134.4, 134.9, 148.4, 148.6, 163.2, 163.4; 31P{1H} NMR δ 62.4;
MS (MALDI-TOF) m/z 397 (M+).
1
9O: Mp 177-178 °C; H NMR δ 1.27 (m, 1H), 1.39 (s, 6H),
1.40 (s, 6H), 1.60 (s, 6H), 1.67 (s, 6H), 1.82 (m, 1H), 2.11 (m,
4H), 5.76 (dd, 2H, J ) 2.6, 2.6 Hz), 5.78 (dd, 2H, J ) 2.6, 2.6
Hz), 6.05 (s, 2H), 7.51 (m, 3H), 7.96 (m, 2H), 9.57 (s, 2H); 13C{1H}
NMR δ 22.6, 22.8, 23.3, 23.6, 23.7, 24.4, 24.6, 25.4, 25.7, 25.8,
25.9, 29.0, 29.2, 29.7, 29.8, 34.1, 36.0, 36.1, 37.6, 37.7, 60.2, 60.5,
100.2, 100.3, 100.9, 103.6, 103.8, 104.2, 130.1, 131.1, 131.2, 131.3,
133.5, 133.7, 134.4, 134.9, 137.9, 138.9, 139.2, 146.8, 147.0, 159.6,
159.7, 168.8, 169.0; 31P{1H} NMR δ 69.4; MS (MALDI-TOF)
m/z 595 (M+).
Synthesis of Compounds 10S and 10O. Compounds 5 (110
mg, 0.25 mmol) and 8S (50 mg, 0.25 mmol) were dissolved in
CH2Cl2 (300 mL), and BF3 · OEt2 (0.014 mL, 0.11 mmol) was added
to the solution. After stirring for 3.5 h at room temperature, the
resulting mixture was washed with distilled water (3 × 150 mL),
dried over Na2SO4, and evaporated. The products were subjected
to silica gel column chromatography (hexane/CH2Cl2 ) 2:1) to give
the asymmetric σ4-P,N2,S-hybrid 10S as a colorless solid (Rf )
0.3; 75 mg, 49%). A similar treatment of 5 with 8O afforded the
asymmetric σ4-P,N2,O-hybrid 10O as a colorless solid (Rf ) 0.3;
44%).
1
10S: Mp 252-253 °C; H NMR δ 1.14 (s, 3H), 1.32 (s, 3H),
1.45 (d, 3H, J ) 2.1 Hz), 1.64-1.75 (m, 17H), 1.80-2.02 (m,
1H), 2.10-2.26 (m, 1H), 2.40-2.55 (m, 1H), 2.73-2.79 (m, 1H),
5.63 (dd, 1H, J ) 3.0, 3.0 Hz), 5.68 (dd, 1H, J ) 3.0, 3.0 Hz),
5.82 (dd, 1H, J ) 3.0, 3.0 Hz), 5.90 (dd, 1H, J ) 3.0, 3.0 Hz),
6.85 (pseudo s, 2H), 7.26-7.60 (m, 4H), 7.84 (s, 1H), 8.40-8.52
(m, 1H), 8.93 (s, 1H); 13C{1H} NMR δ 22.7, 22.8, 22.9, 23.4, 23.5,
24.1, 24.2, 26.4, 26.5, 29.5, 30.0, 30.2, 30.4, 34.1, 34.2, 37.4, 37.6,
38.2, 38.3, 59.5, 59.9, 99.6, 100.4, 101.0, 103.4, 120.9, 121.3, 130.9,
131.4, 131.4, 131.9, 133.1, 133.3, 134.2, 134.2, 135.3, 139.7, 139.7,
141.2, 142.1, 147.0, 147.2, 153.7, 155.7, 168.7, 169.0; 31P{1H}
NMR (toluene-d8) δ 62.3; MS (MALDI-TOF) m/z 610 (M+). Anal.
Calcd for C37H43N2PS2: C, 72.75; H, 7.10; N, 4.59; P, 5.07. Found:
C, 72.99; H, 7.14; N, 4.53; P, 5.37.
1
10O: Mp ca. 240 °C (dec); H NMR δ 1.23 (s, 3H), 1.43 (s,
Synthesis of Compounds 9S and 9O. Compounds 4 (50 mg,
0.11 mmol) and 8S (22 mg, 0.11 mmol) were dissolved in CH2Cl2
(80 mL), and the solution was bubbled with N2 for 40 min.
BF3 · OEt2 (0.014 mL, 0.11 mmol) was added to the solution, and
the mixture was then stirred for 3.5 h at room temperature. The
resulting mixture was washed with distilled water (3 × 80 mL),
dried over Na2SO4, and evaporated to give a pale yellow solid,
which was subjected to silica gel column chromatography (hexane/
CH2Cl2 ) 2:1) to give the σ4-P,S,N2-hybrid 9S as a yellow solid
(Rf ) 0.4; 41 mg, 61%). A similar treatment of 4 with 8O afforded
the σ4-P,N2,O-hybrid 9O as a yellow solid (Rf ) 0.4; 39%).
3H), 1.51 (d, 3H, J ) 2.4 Hz), 1.61-1.79 (m, 17H), 1.89-1.99
(m, 1H), 2.12-2.26 (m, 1H), 2.48-2.56 (m, 1H), 2.77-2.82 (m,
1H), 5.63 (dd, 1H, J ) 3.0, 3.0 Hz), 5.65 (dd, 1H, J ) 3.0, 3.0
Hz), 5.75 (dd, 1H, J ) 3.0, 3.0 Hz), 5.89 (dd, 1H, J ) 3.0, 3.0
Hz), 6.04 (d, 1H, J ) 2.8 Hz), 6.05 (d, 1H, J ) 2.8 Hz), 7.3-7.7
(br, 4H), 8.4-8.7 (br, 1H), 9.00 (s, 1H), 9.32 (s, 1H); 13C{1H}
NMR δ 22.6, 22.8, 23.3, 23.6, 23.7, 24.4, 24.6, 25.4, 25.7, 25.9,
25.9, 29.0, 29.2, 29.7, 29.8, 34.1, 36.0, 36.1, 37.6, 37.7, 60.2, 60.5,
100.2, 100.3, 100.5, 100.9, 103.6, 103.8, 104.2, 130.1, 131.1, 131.3,
131.3, 131.4, 133.5, 133.7, 134.4, 137.9, 138.9, 138.9, 139.2, 146.8,

Phosphole-Containing Hybrid Calixpyrroles
Organometallics, Vol. 27, No. 13, 2008 3151
14.70, 159.7, 159.7, 168.8, 169.0; 31P{1H} NMR δ 63.1; MS
(MALDI-TOF) m/z 595 (M+).
(m, 1H), 2.14-2.26 (m, 2H), 5.82 (dd, 2H, J ) 3.2, 3.2 Hz), 5.87
(dd, 2H, J ) 3.2, 3.2 Hz), 6.98 (s, 2H), 7.43-7.49 (m, 2H),
7.51-7.57 (m, 3H), 7.64-7.72 (m, 2H); 13C{1H} NMR δ 26.9,
26.9, 27.8, 27.9, 28.2, 28.2, 30.9, 31.5, 31.6, 31.8, 36.9, 37.1, 38.0,
100.1, 103.5, 103.5, 125.4, 125.9, 126.7, 129.5, 129.6, 132.5, 132.5,
133.4, 133.6, 135.4, 136.1, 137.3, 137.4, 140.8, 150.6, 161.6, 161.8;
31P{1H} NMR δ 53.8; HR-FAB-MS calcd for C37H43N2ClPSAu
(M+) 810.2239, found 810.2242.
Synthesis of Compound 1X. To a degassed solution of 9S (47
mg, 0.077 mmol) in toluene (5 mL) was added P(NMe2)3 (0.040
mL, 0.22 mmol), and the mixture was then stirred under reflux for
33 h. The resulting mixture was concentrated under reduced pressure
and subjected to silica gel column chromatography (hexane/CH2Cl2
) 2:1) to give the symmetric σ3-P,N2,S-hybrid 1S as a colorless
solid (Rf ) 0.5; 41 mg, 92%). A similar treatment of 9O with
P(NMe2)3 afforded the symmetric σ3-P,N2,O-hybrid 1O as a
colorless solid (Rf ) 0.5; 72%).
1
11out: H NMR δ 1.25 (s, 6H), 1.58 (s, 6H), 1.68 (s, 6H), 1.69
(s, 6H), 1.83-1.94 (m, 1H), 2.06-2.19 (m, 3H), 2.33-2.43 (m,
2H), 5.62 (dd, 2H, J ) 3.0, 3.0 Hz), 5.76 (dd, 2H, J ) 3.0, 3.0
Hz), 6.8-7.3 (br, 2H), 6.88 (s, 2H), 7.07 (br s, 2H), 7.30-7.33
(m, 2H), 7.42-7.46 (m, 1H); 31P{1H} NMR δ 52.1.
1
1S: The H NMR spectrum of 1S indicated that, in toluene-d8,
two conformers are present in about 4:1 ratio. Major conformer:
1H NMR (toluene-d8) δ 1.39 (s, 6H), 1.46 (s, 6H), 1.61 (s, 6H),
1.63 (s, 6H), 1.7-2.3 (m, 6H), 5.95 (m, 2H), 5.96 (m, 2H), 6.63
(s, 2H), 6.9-7.1 (m, 3H), 7.34 (m, 2H), 7.43 (br s, 2H); 31P{1H}
Synthesis of Compounds 12in and 12out. To a Schlenk tube
containing 2Sin (8 mg, 0.014 mmol) and AuCl(SMe2) (4.5 mg, 0.015
mmol) was added 1 mL of CH2Cl2. After stirring for 0.5 h at room
temperature, the resulting mixture was evaporated and subjected
to silica gel column chromatography (hexane/CH2Cl2 ) 1:1) to give
12in as a pale yellow solid (Rf ) 0.4; 9 mg, 80%). A similar
treatment of 2Sout with AuCl(SMe2) afforded the complex 12out as
a colorless solid (Rf ) 0.4; 92%).
1
NMR (toluene-d8) δ 32.1. Minor conformer: H NMR (toluene-
d8) δ 1.30 (s, 6H), 1.57 (s, 6H), 1.58 (s, 6H), 1.61 (s, 6H), 1.7-2.3
(m, 6H), 5.79 (m, 2H), 5.88 (m, 2H), 6.60 (s, 2H), 6.9-7.1 (m,
3H), 7.34 (m, 4H); 31P{1H} NMR (toluene-d8) δ 31.4; HR-FAB-
MS calcd for C37H43N2PS (M+) 578.2885, found 578.2896.
1O: The 1H NMR spectrum of 1O indicated that, in toluene-d8,
two conformers are present in about 5:1 ratio. Major conformer:
1H NMR (toluene-d8) δ 1.34 (s, 6H), 1.48 (s, 6H), 1.54 (s, 6H),
1.64 (s, 6H), 1.6-2.5 (m, 6H), 5.70 (m, 2H), 5.85 (m, 2H), 6.04
(s, 2H), 6.9-7.2 (m, 5H), 7.72 (br s, 2H); 31P{1H} NMR (toluene-
d8) δ 32.3. Minor conformer: 1H NMR (toluene-d8) δ 1.34 (s, 6H),
1.45 (s, 6H), 1.57 (s, 6H), 1.64 (s, 6H), 1.6-2.5 (m, 6H), 5.47 (m,
2H), 5.70 (m, 2H), 5.94 (s, 2H), 6.63 (br s, 2H), 6.9-7.2 (m, 5H);
31P{1H} NMR (toluene-d8) δ 37.6; HR-FAB-MS calcd for
C37H43N2PO (M+) 562.3113, found 562.3099.
1
12in: Mp ca. 240 °C (dec); H NMR δ 1.13 (s, 3H), 1.24-1.39
(m, 1H), 1.43 (s, 3H), 1.55 (s, 3H), 1.65 (pseudo s, 6H), 1.69 (s,
3H), 1.70-1.92 (m, 2H), 1.77 (s, 3H), 1.81 (s, 3H), 2.02-2.18
(m, 1H), 2.28-2.37 (m, 1H), 2.77-2.82 (m, 1H), 5.70-5.72 (m,
2H), 5.88 (dd, 1H, J ) 3.0, 3.0 Hz), 5.93 (dd, 1H, J ) 3.0, 3.0
Hz), 6.97 (br s, 1H), 6.98 (d, 1H, J ) 3.6 Hz), 7.15 (d, 1H, J ) 3.6
Hz), 7.30 (br s, 1H), 7.4-8.3 (br, 2H), 7.46-7.56 (m, 3H); 13C{1H}
NMR δ 22.5, 22.6, 23.8, 23.9, 26.5, 26.5, 26.6, 29.4, 29.7, 30.1,
30.5, 31.2, 31.3, 34.5, 37.2, 37.3, 38.4, 38.5, 62.7, 62.9, 99.6, 101.8,
102.9, 104.5, 122.5, 122.9, 128.4, 129.0, 129.2, 129.4, 129.9, 130.5,
131.3, 131.6, 131.6, 131.8, 132.3, 132.3, 138.2, 138.2, 141.0, 142.0,
148.4, 148.5, 153.2, 154.9, 168.4, 168.6; 31P{1H} NMR δ 48.8;
HR-FAB-MS calcd for C37H43N2ClPSAu (M+) 810.2239, found
810.2252.
Synthesis of Compounds 2Sin and 2Sout. To a degassed solution
of 10S (140 mg, 0.23 mmol) in toluene (20 mL) was added
P(NMe2)3 (5.5 mL, 30 mmol), and the mixture was then stirred
under reflux for 60 h. The resulting mixture was concentrated under
reduced pressure and subjected to silica gel column chromatography
(hexane/CH2Cl2 ) 2:1) to give the asymmetric σ3-P,N2,S-hybrids
2Sout (Rf ) 0.4; 32 mg, 24%) and 2Sin (Rf ) 0.2; 80 mg, 60%) as
a colorless solid, respectively.
12out: Mp 294-296 °C; 1H NMR δ 1.20-1.37 (m, 1H), 1.28 (s,
3H), 1.58 (s, 3H), 1.63-1.75 (m, 10H), 1.78-1.93 (m, 2H), 1.85
(s, 3H), 1.89 (s, 3H), 2.03 (s, 3H), 2.18-2.32 (m, 1H), 2.55-2.65
(m, 1H), 5.80 (dd, 1H, J ) 3.0, 3.0 Hz), 5.84 (dd, 1H, J ) 3.0, 3.0
Hz), 5.87 (dd, 1H, J ) 3.0, 3.0 Hz), 5.94 (dd, 1H, J ) 3.0, 3.0
Hz), 6.73 (br s, 1H), 6.82 (d, 1H, J ) 3.3 Hz), 6.88 (d, 1H, J ) 3.3
Hz), 7.09 (br s, 1H), 7.43-7.48 (m, 2H), 7.52-7.64 (m, 3H);
13C{1H} NMR δ 23.4, 23.6, 23.8, 24.4, 24.5, 26.0, 26.2, 27.1, 29.5,
29.6, 30.5, 30.9, 32.2, 32.3, 35.4, 37.9, 38.1, 38.3, 38.3, 62.9, 63.1,
100.7, 103.2, 103.9, 103.9, 106.5, 121.1, 121.5, 127.0, 127.9, 129.4,
129.5, 129.8, 130.5, 131.9, 131.9, 132.3, 132.4, 133.1, 133.2, 133.4,
138.5, 138.5, 140.4, 140.6, 149.7, 149.9, 154.1, 154.5, 169.4, 169.6;
31P{1H} NMR δ 41.9; HR-FAB-MS calcd for C37H43N2ClPSAu
(M+) 810.2239, found 810.2240.
1
2Sin: Mp ca. 90 °C (dec); H NMR δ 1.01 (s, 3H), 1.15-1.33
(m, 1H), 1.28 (s, 3H), 1.40 (s, 3H), 1.60-1.65 (m, 9H), 1.69 (s,
3H), 1.72 (s, 3H), 1.77-2.05 (m, 3H), 2.10-2.22 (m, 1H),
2.60-2.75 (m, 1H), 5.69 (dd, 1H, J ) 3.0, 3.0 Hz), 5.75 (dd, 1H,
J ) 3.0, 3.0 Hz), 5.90-5.91 (m, 2H), 6.81 (d, 1H, J ) 3.3 Hz),
6.83 (d, 1H, J ) 3.3 Hz), 6.88 (br s, 1H), 7.03 (br s, 1H), 7.25-7.40
(m, 3H), 7.52-7.63 (m, 2H); 31P{1H} NMR δ 29.5; HR-FAB-MS
calcd for C37H43N2PS (M+) 578.2885, found 578.2894.
1
2Sout: Mp ca. 70 °C (dec); H NMR δ 1.19 (s, 3H), 1.20-1.30
(m, 1H), 1.53 (s, 3H), 1.58-1.67 (m, 10H), 1.71 (s, 3H), 1.75-1.90
(m, 2H), 1.81 (s, 3H), 1.93 (s, 3H), 1.99-2.07 (m, 1H), 2.45-2.52
(m, 1H), 5.71 (dd, 1H, J ) 3.2, 3.2 Hz), 5.82-5.86 (m, 3H), 6.84
(pseudo s, 2H), 7-8 (br, 2H), 7.06 (br s, 1H), 7.21-7.35 (m, 4H);
31P{1H} NMR δ 17.7; HR-FAB-MS calcd for C37H43N2PS (M+)
578.2885, found 578.2877. We were not successful in obtaining
satisfactory 13C NMR spectra of 2Sin and 2Sout because of the
gradual interconversion between these two conformers in CDCl3
solution during the prolonged measurement time.
Synthesis of Compounds 13i-i, 13i-o, and 13o-o. To a Schlenk
tube containing 1S (20 mg, 0.034 mmol) and PtCl2 (4.5 mg, 0.017
mmol) was added 2.0 mL of toluene, and the resulting mixture
was heated under reflux for 2 h. The solution was evaporated and
subjected to silica gel column chromatography (CH2Cl2/hexane )
2:1), affording the bisphosphine complexes 13i-i (Rf ) 0.5; 3 mg,
12%), 13i-o (Rf ) 0.3; 15 mg, 60%), and 13o-o (Rf ) 0.2; 6 mg,
24%) as a pale yellow solid, respectively. When the reaction time
was 4 days, complex 13i-i was obtained exclusively (85%); small
amounts of 13i-o (ca. 10%) and 13o-o (trace) were also observed in
Synthesis of Compounds 11in and 11out. To a Schlenk tube
containing 1S (57 mg, 0.099 mmol) and AuCl(SMe2) (32 mg, 0.11
mmol) was added 3 mL of toluene. After stirring for 1 h at room
temperature, the resulting mixture was evaporated and subjected
to silica gel column chromatography (hexane/CH2Cl2 ) 2:1) to give
11in as a colorless solid (Rf ) 0.5; 66 mg, 86%). When the reaction
time was 15 min, a small amount of 11out (ca. 10%) was observed
1
the H NMR spectrum of the crude products.
13i-i: Mp ca. 290 °C (dec); 1H NMR δ 0.92-1.04 (m, 4H), 1.23
(s, 12H), 1.60-1.72 (m, 28H), 1.88-2.05 (m, 4H), 2.09 (s, 12H),
5.76-5.79 (m, 8H), 6.41 (s, 4H), 7.34-7.38 (m, 4H), 7.45-7.49
(m, 2H), 7.86-7.90 (m, 4H), 8.85 (s, 4H); 13C{1H} NMR δ 26.1,
26.8, 30.7, 31.5, 34.4, 37.8, 38.0, 38.1, 38.1, 99.4, 102.5, 124.7,
125.7, 125.9, 126.1, 128.2, 128.2, 128.3, 130.6, 132.8, 132.8, 132.9,
138.4, 138.7, 138.9, 141.6, 142.1, 150.6, 163.5, 163.6, 163.7;
by H and 31P NMR spectra.
1
1
11in: Mp ca. 220 °C (dec); H NMR δ 1.34 (s, 6H), 1.54 (s,
6H), 1.55-1.69 (m, 3H), 1.67 (s, 6H), 1.75 (s, 6H), 1.85-1.97

3152 Organometallics, Vol. 27, No. 13, 2008
Nakabuchi et al.
31P{1H} NMR δ 46.7 (JPt-P ) 2476 Hz); HR-FAB-MS calcd for
C74H86N4Cl2P2S2Pt (M+) 1421.4794, found 1421.4780. Anal. Calcd
for C74H86N4Cl2P2S2Pt: C, 62.43; H, 6.09; N, 3.94. Found: C, 62.09;
H, 6.38; N, 3.51.
33.2, 37.7, 37.8, 37.9, 38.0, 38.3, 61.8, 62.0, 62.1, 99.7, 101.4,
101.8, 104.6, 121.6, 121.9, 127.6, 127.6, 127.7, 127.8, 128.2, 128.4,
128.7, 129.4, 129.8, 130.1, 130.3, 133.6, 134.5, 134.5, 134.6, 141.1,
141.1, 141.1, 141.3, 142.0, 150.5, 152.3, 155.6, 166.0, 166.1, 166.2;
31P{1H} NMR δ 40.2 (JPt-P ) 2421 Hz); HR-FAB-MS calcd for
C74H86N4Cl2P2S2Pt (M+) 1421.4794, found 1421.4819.
1
13i-o: Mp ca. 230 °C (dec); H NMR δ 1.28 (s, 6H), 1.45 (s,
6H), 1.55-1.70 (m, 32H), 1.77-2.10 (m, 8H), 2.25 (s, 6H),
2.43-2.48 (m, 2H), 5.67 (dd, 2H, J ) 3.0, 3.0 Hz), 5.80-5.82 (m,
6H), 6.55 (s, 2H), 6.84 (s, 2H), 7.19 (s, 2H), 7.35-7.46 (m, 6H),
7.53 (m, 2H), 7.92 (m, 2H), 8.91 (s, 2H); 13C{1H} NMR δ 14.1,
22.7, 25.7, 26.6, 26.7, 26.7, 26.9, 26.9, 27.4, 28.3, 28.3, 28.4, 29.0,
30.3, 30.4, 30.4, 30.5, 30.8, 31.3, 31.6, 31.6, 35.5, 35.5, 37.8, 37.9,
38.0, 38.4, 38.5, 38.6, 99.4, 101.5, 102.5, 103.1, 123.6, 124.4, 126.0,
126.7, 127.3, 127.9, 127.9, 128.0, 128.6, 128.7, 128.8, 130.3, 130.9,
132.8, 132.9, 132.9, 134.4, 134.5, 134.6, 138.1, 138.6, 138.8, 138.9,
139.0, 139.0, 139.2, 142.0, 142.1, 142.1, 142.2, 151.0, 152.2, 159.3,
16i-i: Mp ca. 220 °C (dec); 1H NMR δ 0.86 (s, 6H), 1.10-1.25
(m, 2H), 1.35 (s, 6H), 1.54 (s, 6H), 1.60 (s, 6H), 1.62-1.79 (m,
4H), 1.70 (s, 6H), 1.86 (s, 6H), 1.91 (s, 6H), 1.95-2.13 (m, 4H),
2.06 (s, 6H), 2.68-2.74 (m, 2H), 5.67 (dd, 2H, J ) 3.0, 3.0 Hz),
5.72 (dd, 2H, J ) 3.0, 3.0 Hz), 5.81 (dd, 2H, J ) 3.0, 3.0 Hz),
5.91 (dd, 2H, J ) 3.0, 3.0 Hz), 6.05 (d, 2H, J ) 3.6 Hz), 6.52 (d,
2H, J ) 3.6 Hz), 7.45-7.57 (m, 6H), 7.85-7.91 (m, 4H), 8.37 (s,
2H), 9.58 (s, 2H); 13C{1H} NMR δ 22.5, 22.5, 22.6, 22.9, 23.0,
23.0, 26.1, 28.6, 28.6, 28.7, 28.8, 30.8, 31.1, 31.5, 33.0, 33.6, 33.6,
33.7, 37.7, 37.8, 37.9, 38.0, 38.3, 62.1, 62.2, 62.3, 99.7, 101.4,
101.9, 104.6, 121.7, 122.0, 127.6, 127.7, 127.8, 128.3, 128.6, 128.9,
129.2, 129.4, 129.6, 130.2, 130.8, 131.1, 131.4, 133.3, 134.6, 134.6,
134.7, 140.7, 140.8, 140.8, 141.4, 142.1, 150.3, 150.4, 150.6, 152.2,
155.7, 165.4, 165.5, 165.6; 31P{1H} NMR δ 44.0; HR-FAB-MS
calcd for C74H86N4Cl2P2S2Pd (M+) 1332.4181, found 1332.4186.
X-ray Crystallography. Single crystals suitable for X-ray
159.4, 159.5, 163.2, 163.4, 163.5; 31P{1H} NMR δ 45.5 (JPt-P
)
2400 Hz), 46.5 (JPt-P ) 2560 Hz); HR-FAB-MS calcd for
C74H86N4Cl2P2S2Pt (M+) 1421.4794; found 1421.4780.
1
13o-o: Mp ca. 220 °C (dec); H NMR δ 1.51 (s, 12H), 1.66 (s,
12H), 1.68 (s, 12H), 1.69 (s, 12H), 1.75-2.05 (m, 8H), 2.35-2.46
(m, 4H), 5.70 (dd, 4H, J ) 3.0, 3.0 Hz), 5.79 (dd, 4H, J ) 3.0, 3.0
Hz), 6.85 (s, 4H), 7.16-7.28 (m, 4H), 7.22 (br s, 4H), 7.31-7.35
(m, 2H), 7.54-7.59 (m, 4H); 13C{1H} NMR δ 27.4, 27.9, 28.0,
28.0, 28.7, 30.5, 30.7, 31.3, 37.9, 38.4, 38.5, 38.6, 101.2, 103.1,
123.8, 125.3, 125.6, 125.9, 128.4, 128.4, 128.5, 130.6, 134.5, 134.6,
134.7, 138.3, 138.7, 139.0, 139.2, 152.1, 159.6, 159.7, 159.8;
31P{1H} NMR δ 45.7 (JPt-P ) 2445 Hz); HR-FAB-MS calcd for
C74H86N4Cl2P2S2Pt (M+) 1421.4794, found 1421.4816.
Synthesis of Compound 14i-i. To a Schlenk tube containing 1S
(10 mg, 0.017 mmol) and PdCl2 (1.5 mg, 0.0085 mmol) was added
1.5 mL of toluene, and the resulting mixture was heated under reflux
for 2 h. The solution was evaporated and subjected to silica gel
column chromatography (hexane/CH2Cl2 ) 2:1), affording the
bisphosphine complex 14i-i (Rf ) 0.5; 10 mg, 88%) as a yellow
solid.
analyses were grown from CH2Cl2/MeOH (for 9S, 9O, 10S, 12out
,
13i-i, and 13i-o), CH2Cl2/hexane (for 10O, 11in, and 14i-i), or CH2Cl2/
MeCN (for 15i-i and 16i-i). All X-ray crystallographic measurements
were made on a Rigaku Saturn CCD area detector with graphite-
monochromated Mo KR radiation (0.71070 Å). The selected
crystallographic data are summarized in Table S1. The structures
were solved by using direct methods (SIR9229 for 9O, 11in, 13i-i,
and 16i-i; SIR9730 for 9S, 10S, 10O, 13i-o, and 16i-o; SHELXS9731
for 12out). Non-hydrogen atoms were refined anisotropically, and
hydrogen atoms were refined using the rigid model. All calculations
were performed using the CrystalStructure32 crystallographic
software package except for refinement, which was performed using
SHELXL-97.31 The crystals of 9S consist of a pair of two
independent molecules, one of which is depicted in Figure 2. The
CIF files of 9S and 9O were uploaded as the Supporting Information
files in ref 16.
14i-i: Mp ca. 240 °C (dec); 1H NMR δ 0.93-1.02 (m, 4H), 1.22
(s, 12H), 1.55-1.77 (m, 28H), 1.89-2.01 (m, 4H), 2.09 (s, 12H),
5.75-5.78 (m, 8H), 6.43 (s, 4H), 7.33-7.37 (m, 4H), 7.45-7.49
(m, 2H), 7.86-7.90 (m, 4H), 8.98 (s, 4H);13C{1H} NMR δ 25.9,
26.7, 26.7, 26.8, 27.0, 30.6, 31.5, 35.1, 35.2, 35.2, 37.8, 38.0, 38.1,
38.2, 53.4, 99.4, 102.5, 124.8, 126.2, 126.5, 126.7, 128.2, 128.3,
128.4, 130.6, 133.0, 133.0, 133.1, 134.3, 139.9, 140.1, 140.4, 141.4,
142.2, 150.6, 162.9, 163.0, 163.1;31P{1H} NMR δ 49.4; HR-FAB-
MS calcd for C74H86N4Cl2P2S2Pd (M+) 1332.4181, found 1332.4198.
Synthesis of Compounds 15i-i and 16i-i. To a suspension of PtCl2
(2.3 mg, 0.0085 mmol) in MeOH (0.5 mL) was added a CH2Cl2(1
mL) solution of 2Sin (10 mg, 0.017 mmol). After stirring for 2 h at
room temperature, the resulting mixture was evaporated. Purification
with silica gel column chromatography (hexane/CH2Cl2 ) 2:1)
followed by recrystallization from CH2Cl2/MeOH gave 15i-i as a
pale yellow solid (Rf ) 0.2; 10 mg, 83%). A similar treatment of
2Sin with PdCl2 afforded the complex 16i-i as a yellow solid (Rf )
0.2; 79%).
Acknowledgment. This work was partially supported by
Grants-in-Aid (Nos. 19027030 and 17350018) from the
Ministry of Education, Culture, Sports, Science, and Tech-
nology of Japan. We thank Prof. Hidemitsu Uno (Ehime
University) for his helpful suggestions about X-ray crystal-
lographic analysis. T.N. acknowledges a JSPS fellowship for
young scientists.
Supporting Information Available: ORTEP diagrams of 9O,
10O, and 14i-i and CIF files for 10S, 10O, 11in, 12out, 13i-i, 13i-o,
14i-i, and 16i-i. This material is available free of charge via the
Internet at http://pubs.acs.org.
OM800099H
15i-i: Mp ca. 220 °C (dec); 1H NMR δ 0.85 (s, 6H), 1.10-1.30
(m, 2H), 1.36 (s, 6H), 1.54 (s, 6H), 1.59 (s, 6H), 1.62-1.79 (m,
4H), 1.69 (s, 6H), 1.88 (s, 6H), 1.93 (s, 6H), 1.95-2.13 (m, 4H),
2.07 (s, 6H), 2.69-2.75 (m, 2H), 5.66 (dd, 2H, J ) 2.8, 2.8 Hz),
5.71 (dd, 2H, J ) 2.8, 2.8 Hz), 5.80 (dd, 2H, J ) 2.8, 2.8 Hz),
5.92 (dd, 2H, J ) 2.8, 2.8 Hz), 6.03 (d, 2H, J ) 3.6 Hz), 6.47 (d,
2H, J ) 3.6 Hz), 7.45-7.57 (m, 6H), 7.87-7.93 (m, 4H), 8.24 (s,
2H), 9.34 (s, 2H); 13C{1H} NMR δ 22.4, 22.6, 22.6, 22.7, 23.0,
23.1, 26.1, 27.9, 28.0, 28.1, 28.8, 30.8, 30.9, 31.5, 33.0, 33.1, 33.2,
(29) SIR92: Altomare, A.; Cascarano, G.; Giacovazzo, C.; Guagliardi,
A.; Burla, M.; Polidori, G.; Camalli, M. J. Appl. Crystallogr. 1994, 27,
435.
(30) SIR97: Altomare, A.; Burla, M.; Camalli, M.; Cascarano, G.;
Giacovazzo, C.; Guagliardi, A.; Moliterni, A.; Polidori, G.; Spagna, R.
J. Appl. Crystallogr. 1999, 32, 115–119.
(31) Sheldrick, G. M. SHELXL-97; University of Go¨ttingen: Germany,
1997.
(32) CrystalStructure 3.8.0: Crystal Structure Analysis Package; Rigaku
and Rigaku/MSC: The Woodlands, TX, 2000-2006.