Luminescent benzoquinolate-isocyanide platinum(II) complexes: Effect of Pt...Pt and π...π interactions on their photophysical properties

Article abstract of DOI:10.1002/asia.201200585

The neutral compounds [Pt(bzq)(CN)(CNR)] (R=tBu (1), Xyl (2), 2-Np (3); bzq= benzoquinolate, Xyl=2,6-dimethylphenyl, 2-Np=2-napthyl) were isolated as the pure isomers with a trans-C_bzq,CNR configuration, as confirmed by ¹³C{¹

Full text of DOI:10.1002/asia.201200585

DOI: 10.1002/asia.201200585
Luminescent Benzoquinolate-Isocyanide Platinum(II) Complexes: Effect of
Pt···Pt and p···p Interactions on their Photophysical Properties
Juan Forniꢀs,*[a] Violeta Sicilia,*[b] Pilar Borja,[a] Josꢀ M. Casas,[a] Alvaro Dꢁez,[c]
Elena Lalinde,[c] Carmen Larraz,[a] Antonio Martꢁn,[a] and M. Teresa Moreno[c]
Abstract: The neutral compounds [Pt-
(bzq)(CN)(CNR)] (R=tBu (1), Xyl
(2), 2-Np (3); bzq= benzoquinolate,
Xyl=2,6-dimethylphenyl, 2-Np=2-
configuration, has been selectively iso-
lated from [Pt(bzq)Cl(CNXyl)] (trans-
bzq,CNR) using Sonogashira condi-
tions. X-ray diffraction studies reveal
that while 1 adopts a columnar-stacked
chain structure with Pt–Pt distances of
3.371(1) ꢀ and significant p···p interac-
tions (3.262 ꢀ), complex
2
forms
G
E
T
N
dimers supported only by short Pt···Pt
(3.370(1) ꢀ) interactions. In complex 4
the packing is directed by weak
bzq···Xyl and bzq···CꢁE (C, N) inter-
actions. In solid state at room tempera-
ture, compounds 1 and 2 both show
a bright red emission (f=42.1% 1,
57.6% 2). Luminescence properties in
the solid state at 77 K and concentra-
tion-dependent emission studies in
CH2Cl2 at 298 K and at 77 K are also
reported for 1-4.
N
napthyl) were isolated as the pure iso-
mers with a trans-Cbzq,CNR configura-
tion, as confirmed by 13C{1H} NMR
spectroscopy in the isotopically marked
[PtACHTUNGTRENNUNG(bzq)ACHTUNGTRENNUNG ACHTUNGTRENNUNG(CNR)] (R=tBu (1’),
(13CN)
Keywords: coordination chemistry ·
metallophilic interactions · pi inter-
actions · platinum · stacking interac-
tions
Xyl (2’), 2-Np (3’)) derivatives (d13CCN
ꢂ110 ppm; 1J
ACHTUNGTRENNUNG
contrast, complex [Pt
(bzq)
G
ACHTUNGTRENNUNG(CNXyl)] (4) with a trans-Nbzq,CNR
Introduction
a small contribution from covalent Pt···Pt bonding interac-
tions is also present.[6] Such linear-chain structures have
been observed not only for complex salts but also for anion-
ic, cationic, or neutral complexes. Illustrative examples are
It is well known that square-planar PtII complexes show a re-
markable tendency to self-assemble into one-dimensional
(1D) architectures directed by PtII···PtII interactions.[1] Typi-
cal are the double complex salts (DCS) consisting of infinite
alternating stacks of cations and anions with the platinum
atoms aligned linearly and separated by approximately
ACTHNUTRGNEUNG
found in the salts of [Pt(CN)4]2ꢀ,[7] [Pt(Nttpy)Cl]2+ (Nttpy=
4’-(p-nicotinamide-N-methylphenyl)-2,2’:6’,2“-terpyridine),[8]
+
ꢀ
[Pt
G
E
C6H5, 4-OCH3-C6H4)[9–10] and [Pt
tral complexes [PtCl2A
(bpy)] (bpy=bipyridine),[12] [Pt(CN)2
(bpy)],[13] [Pt(bpm)Cl2] (bpm=2,2’-bipyrimidine),[14] [Pt-
(phen)(CN)2] [Pt(bpy)-
(phen=phenanthroline),[14]
(NCS)2],[14] [cis-Pt (C2H5)C6H4)2(CN)2],[15] [trans-Pt-
(CN-p-
(CN-p-
(C2H5)C6H4)2(CN)2],[16] [Pt(CNtBu)2(CN)2][17] and
[Pt(bzq)Cl
(CNtBu)].[18] (bzq=benzoquinolate; dPt···Pt =3.09
(tpy)Cl]+,[11] and in the neu-
ACHTUNGTRENNUNG
3.3 ꢀ, as the Magnus salt [Pt
[Pt(NH2R)4] (CNR)4]
[PtCl4][3] or [Pt
known DCS [Pt
(CNR)4][Pt(CN)4].[4–5] In these cases stack-
C
N
G
G
A
U
A
ACHTUNGTRENNUNG
G
N
ing is largely controlled by electrostatic interactions, but
T
G
[a] J. Forniꢂs, P. Borja, J. M. Casas, C. Larraz, A. Martꢃn
Instituto de Sꢃntesis Quꢃmica y Catꢄlisis Homogꢂnea (ISQCH)
CSIC—Universidad de Zaragoza
to 3.60 ꢀ). The presence in the complexes of nonbulky p-
conjugated systems such as diimine, terpyridyl, or C,N-cyclo-
metalated ligands adds p···p interactions to the PtII···PtII in-
teractions as the major forces that determine the supra-
molecular structures.[19–20] Significant contribution to the
structureꢁs stability is observed when the Pt···Pt distance is
less than 3.5 ꢀ[6] and the separation between aromatic
groups[21] no more than 3.8 ꢀ.
Departamento de Quꢃmica Inorgꢄnica, Facultad de Ciencias
Pedro Cerbuna 12, 50009 Zaragoza (Spain)
E-mail: juan.fornies@unizar.es
[b] V. Sicilia
Instituto de Sꢃntesis Quꢃmica y Catꢄlisis Homogꢂnea (ISQCH)
CSIC—Universidad de Zaragoza
Departamento de Quꢃmica Inorgꢄnica
As result of Pt···Pt and/or p···p interactions, stacked
Escuela de Ingenierꢃa y Arquitectura de Zaragoza
Campus Rꢃo Ebro, Edificio Torres Quevedo, 50018, Zaragoza (Spain)
square-planar PtII complexes very often show intense colors
3
3
[c] A. Dꢃez, E. Lalinde, M. T. Moreno
Departamento de Quꢃmica - Grupo de Sꢃntesis Quꢃmica de La Rioja
UA-CSIC, Universidad de La Rioja
26006, LogroÇo (Spain)
and luminescence due to an emission from a MMLCT
-
(ds*(Pt)2!p*(L)) excited state that strongly depends on
the extent of such stacking interactions; these photophysical
properties are therefore very different from those of the iso-
lated mononuclear complexes.[22] Ground-state aggregation
or oligomerization through PtII···PtII and p···p interactions
Fax : (+34)941-299621
Supporting information for this article is available on the WWW
under http://dx.doi.org/10.1002/asia.201200585.
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FULL PAPER
exist not only in the solid state but also in solution; that is,
strategies followed only allowed us to obtain the (trans Cbzq
CNR) isomer of [Pt(bzq)(CN)(CNR)] (R=tBu (1), Xyl (2),
2-Np (3)) as pure samples. For the purpose of comparison
with the isoelectronic complex 2, compound [Pt(bzq)-
(CNXyl)] (4; trans-Nbzq,CNR) was also prepared,
-
+
ꢀ
aggregation of [Pt
(tpy)
N
E
ACHTUNGTRENNUNG
OCH3-C6H4) is induced by the variation of solvent composi-
tion, causing drastic changes in the absorption and emission
colors with no precipitation of the higher nuclearity spe-
cies.[9–10,23] Environmental factors such as solvent, vapors,
and counterion can perturb the weak Pt···Pt and/or p···p in-
teractions and subsequently modify their associated photo-
physical properties.[22,24] In fact, some 1D PtII compounds
have been shown to exhibit vapochromic and vapolumines-
ACHTUNGTRENNUNG
G
ACHTUNGTRENNUNG
and the photophysical properties of all of them have been
also examined.
Results and Discussion
Synthesis and Characterization
cent properties, such as the stacked double salts [PtACTHNUTRGNEUNG(CNR)4]
[M(CN)4][25] and the neutral complexes [PtII(CN-i-
C3H7)2(CN)2][26] and cis-[Pt(p-CN-C6H4-C2H5)2(CN)2].[15]
In the course of our research we have prepared the chloro
With the aim of preparing the neutral compounds [Pt-
ACHUTNGERN(NUG bzq)(CN)ACHUTNGTRENN(UNG CNR)] (R=tBu, Xyl, 2-Np) as pure single iso-
isocyanide complexes [Pt
(bzq)Cl
E
mers, various strategies were followed. The first consisted of
the addition of the equimolar amount of KCN to a solution
of [PtACHTNUTRGENN(UG bzq)CAHTUNGTERNN(GUN CNR)2]ClO4 (R=tBu, Xyl, 2-Np) in dichlorome-
Np)[18] and studied their intriguing structural and photophys-
ical properties. As considerable experimental work has dem-
onstrated that the electronic properties of the ligands have
a primary effect on the strength of Pt···Pt interactions, with
stronger field and p-acidic ligands enhancing the interac-
tions,[1,27–28] we decided to investigate the effect, if any, of
the substitution of the chloride by CNꢀ and CꢁCPhꢀ in the
crystal packing and photophysical properties of the final
compounds.
thane/methanol (see Scheme 1, path a, and the Experimen-
The neutral complexes [Pt
ACHUTGTNRENN(GU bzq)(CN)AHCTUNGTREN(NGUN CNR)] (R=tBu,
Xyl, 2-Np) were first observed in solutions of the double
complex salts (DCS) [PtCAHTUGNRTEN(NNUG bzq)ACHTNURTGEG(NNUN CNR)2][PtACHTNUGRTENN(UGN bzq)(CN)2] (R=
tBu, Xyl, 2-Np).[29] These DCS transform into the corre-
sponding neutral complexes as a mixture of two isomers
1
that could be identified by H and 13C NMR spectroscopy
experiments, but no pure samples of any of them could be
obtained. For this work, we aimed to prepare pure samples
of each isomer of the neutral compounds. The different
Scheme 1. Synthetic strategies to 1–4.
Abstract in Spanish: Los compuestos neutros [Pt
ACHTUNGTRENUN(NG bzq)(CN)-
tal Section). These reactions always proceed with replace-
ACHTUNGTRENNUNG(CNR)] [R=tBu 1, Xyl 2, 2-Np 3] fueron aislados como isꢆ-
ment of CNR trans to N by CNꢀ to give the neutral com-
meros puros con una configuraciꢆn trans-Cbzq,CNR, como se
confirmꢆ por espectroscopꢃa de RMN de 13C{1H} de los deri-
plexes (SP-4-3)-[PtACTHUNRGTENNUG(bzq)(CN)ACHTUNGTERN(NUGN CNR)] (R=tBu (1), Xyl (2),
2-Np (3)), which were obtained from the reaction mixture
as pure samples in very high yields (75–90%). The second
strategy consisted of the treatment of [PtACHTNUTGRENNUG(bzq)ClACHTUNGTRENNUNG(CNR)]
vados marcados isotꢆpicamente [PtACTHUNGTREN(NGUN bzq)ACHNUTRTGENNUNG CAHTNUGTRENN(UGN CNR)] [R=
(13CN)
tBu 1’, Xyl 2’, 2-Np 3’] [d13CCN ꢂ110 ppm; 1J
(Pt,13C)
ACHTUNGTRENNUNG
(CꢁCPh)-
ꢂ1425 Hz]. Por el contrario, el complejo [Pt
(bzq)
G
(R=tBu, Xyl, 2-Np)[18] with AgClO4 (molar ratio 1:1) to ab-
stract the chloride ligand from the coordination sphere of
the platinum center as AgCl(s) and the subsequent addition
of KCN (molar ratio 1:1) to the resulting solutions (see
Scheme 1, path b, and Experimental Section). Work-up of
the reaction mixtures allowed us to obtain the neutral com-
plexes 1–3 as pure samples in moderate yields (48–67%). A
third method consisting of the addition of CNR to a solution
ACHTUNGTRENNUNG
a
N
ACHTUNGTRENNUNG
(trans-Nbzq,CNR) empleando la reacciꢆn de Sonogashira.
Los estudios de difracciꢆn de rayos X revelan que mientras
1 adopta una estructura de apilamiento en columna con dis-
tancias Pt-Pt de 3.371(1) ꢀ e importantes interacciones p···p
(3.262 ꢀ), el complejo 2 forma dꢃmeros unidos solamente
por interacciones Pt···Pt [3.370(1) ꢀ]. En el complejo 4 el
empaquetamiento estꢄ dirigido por dꢂbiles interacciones
bzq···Xyl y bzq···CꢁE (C, N). En estado sꢆlido a temperatu-
ra ambiente los compuestos 1 y 2 muestran una emisiꢆn roja
muy intensa (f=57.6% 2, 42.1% 1). Se describen tambiꢂn
las propiedades luminiscentes en estado sꢆlido a 77 K y en
CH2Cl2 en diversas concentraciones a 298 K y a 77 K de 1–4.
of (NBu4)[PtACTHNUTRGNE(UNG bzq)(CN)2] in dichloromethane was also
checked, but substitution of CNꢀ by CNR was never ob-
served.
Compounds 1–3 were hence obtained in two ways, repre-
sented in Scheme 1 (paths a, b) but with very different
yields. The moderate yields obtained with the second
method (Scheme 1, path b) can be explained because the re-
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Luminescent Benzoquinolate-Isocyanide Platinum(II) Complexes
action always led to mixtures of the two possible isomers
SP-4-2 and SP-4-3 (1H and 13C NMR spectroscopy data are
given in the Experimental Section and the Supporting Infor-
mation), from which only the less soluble one, SP-4-3, could
be isolated as a pure substance.
NEt3) in chloroform gave rise to the compound (SP-4-2)-[Pt-
(bzq) (CNXyl)] (4, 88% yield) with retention of
(CꢁCPh)
G
E
ACHTUNGTRENNUNG
the trans-N,CNR geometry observed in the chloride deriva-
tive (see Scheme 1, path c and the Experimental Section).
The most informative signals in the 13C{1H} NMR spectrum
of 4 are the expected low-field resonance at d=159.1 ppm
with a large 1J(195Pt,13C) coupling constant (712 Hz), as-
signed to the metalated carbon atom of the bzq ligand, and
the resonances of the Ca and Cb alkynyl carbons. The Ca
signal appears at d=118.3 ppm with a platinum coupling
Taking into account that the chloride derivatives [Pt-
A
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
C, CNR geometry, a partial change in the configuration of
the Pt center seems to occur. To gain a better insight into
this process, the addition of a solution of K13CN in methanol
was performed at low temperature (ꢀ788C), and after 1 h
1
constant J(195Pt,13C) of 848 Hz, while the Cb alkyne carbon
appears shifted to higher field (d=107.8 ppm), exhibiting
1
2
the solvent was evaporated to dryness. The H and 13C NMR
a low J(195Pt,13C)=220 Hz. The relatively low 195Pt–Ca,b cou-
spectra of these residues showed the presence of both iso-
mers in each case. These mixtures remained unchanged
after several days at room temperature in CH2Cl2 or after
heating them in refluxing acetone. These experimental re-
sults indicate that the tetra-coordinated (SP-4-2) and (SP-4-
pling constants confirm that the alkynyl fragment is located
trans to metalated Cbzq atom of high trans influence. In fact,
these values are in the range of those obtained for alkynyl
groups located trans to the metalated Cbzq in [Pt
ACHTUNGTRENNUNG(bzq)-
AHCTUNGTRENNUNG
3)-[PtACHTUNGTRENNUNG(bzq)(CN)ACHTUNGTRENNUNG(CNR)] compounds, once formed, do not
isomerize one into the other, even in refluxing acetone.
Therefore, it seems that low-temperature isomerization
could take place on the solvent-coordinated species [Pt-
X-ray Structures
The X-ray studies on compounds 1 and 2 (Figure 2 and
Figure 3) show that they are mononuclear complexes in
which the PtII center is located in distorted square-planar
environments formed by the donor atoms of a bzq group,
a cyanide ligand, and an isocyanide ligand (CNtBu (1),
ACHTUNGTRENNUNG(bzq)ACHTUNGTRENNUNG
(CNR)(S)]+ (S=acetone or acetonitrile) or, more
likely, that the substitution of acetone (OCMe2) by CNꢀ
proceeds without stereoretention.
The air-stable compounds 1–3 were fully characterized
(see the Experimental Section), and for a better characteri-
zation, the isotopically marked compounds (SP-4-3)-[Pt-
A
ACHTUNGTRENNUNG ACHTUNGTRENNUNG(CNR)] (R=tBu (1’), Xyl (2’), 2-Np (3’)) were
(13CN)
ACHUTNGREN(NUG bzq)ACHUTGNTREN(NUGN CNR)2]ClO4 (R=tBu,
Xyl, 2-Np) with K13CN according to path a (Scheme 1). All
the spectroscopic data indicate that these complexes show
a trans Cbzq, CNR configuration.
Of particular significance are the 13C{1H} NMR spectra of
compounds 1’–3’, which show a singlet at approximately d=
110 ppm with the corresponding 195Pt satellites, the
1J(195Pt,13C) being about 1425 Hz, as corresponds to a 13CNꢀ
ligand trans to Nbzq (see Figure 1 for compound 2’).[29]
However, treatment of [PtACTHNUGRTENNUG(bzq)ClACHUTNGTRENN(GUN CNXyl)] with excess
HCꢁCPh in the presence of the catalytic mixture (CuI/
Figure 2. X-ray structure of [PtACTHNUGRTENNUG(bzq)(CN)ACHTUGNTREN(NUGN CNtBu)] (1). Thermal ellip-
soids are set at the 50% probability level. H atoms are omitted for clari-
ty.
Figure 3. X-ray structure of [PtACTHNUGRTENNUG(bzq)(CN)ACHTUGNTREN(NUGN CNXyl)] (2). Thermal ellip-
soids are set at the 50% probability level. H atoms are omitted for clari-
ty.
Figure 1. 13C{1H} NMR spectrum of compound 2’ in CD2Cl2 solution.
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Juan Forniꢂs, Violeta Sicilia et al.
FULL PAPER
CNXyl (2)). In both complexes the CNꢀ is in trans position
to the N atom of the cyclometalated group. In the case of
compound 1, two molecules with slight differences between
each other are present in the crystal. All bond lengths and
angles (Table 1) are similar to those observed in platinum
complexes containing these kinds of ligands (CN,[30–31] cyani-
de[15,31c,32] and isocyanide[15–17,31a,33]).
Table 1. Structural data for compounds 1·CHCl3 and 2·CHCl3.
Distances [ꢀ] and angles [deg]
1(A)·CHCl3
1(B)·CHCl3
2·CHCl3
Pt–CCN
Pt–CCNR
Pt–Cbzq
Pt–Nbzq
1.933(9)
1.989(9)
2.024(7)
2.060(6)
1.161(10)
1.142(11)
3.371(1)
92.7(3)
91.4(3)
94.3(3)
81.6(3)
178.3(7)
179.1(7)
177.0(8)
1.966(8)
2.013(7)
2.022(7)
2.071(6)
1.140(10)
1.120(9)
3.371(1)
91.6(3)
94.0(3)
92.8(3)
81.6(3)
178.0(7)
178.7(6)
173.8(8)
1.961(2)
1.980(3)
2.029(2)
2.067(2)
1.155(3)
1.165(3)
3.370(1)
92.39(9)
90.67(9)
95.73(9)
81.15(8)
177.9(2)
179.5(2)
172.6(2)
Figure 4. Molecular structure of [Pt
ellipsoids are set at the 50% probability level. H atoms are omitted for
clarity.
G
E
ACHTUNGTREN(NUNG CNXyl)] (4). Thermal
C
CN–NCN
CCNR–NCNR
Pt–Pt
Table 2. Selected structural data for [Pt
Distances [ꢀ] and angles [deg]
ACHTUNGTREN(NUNG CN-Xyl)] (4).
CCN-Pt-Cbzq
CCN-Pt-CCNR
Nbzq-Pt-CCNR
Nbzq-Pt-Cbzq
Pt-CCN-NCN
Pt-CCNR-NCNR
C-NCNR-C
Pt–CCꢁCPh
Pt–Cbzq
C–CCꢁC
2.053(13)
2.051(13)
1.154(19)
1.387(17)
95.1(5)
90.3(6)
175.4(13)
175.6(13)
1.908(14)
2.097(10)
1.110(16)
CXyl–N
Nbzq-Pt-CCꢁCPh
Cbzq-Pt-CCNR
91.0(6)
83.5(5)
176.2(15)
171.1(14)
Pt-Ca-Cb
CꢁCPh
Pt-C-NCNR
Both the cyanide and isocyanide ligands are almost linear-
ly coordinated to the platinum center, with bond angles for
C and N close to 1808. Complexes 1 and 2 are almost
planar; the CNꢀ ligand is in the Pt coordination plane
the CNXyl ligand is slightly stronger than that of the Cꢁ
CPh group. Bond lengths and angles are in the usual ranges
for this type of complexes. Both the CNXyl (175.6(13)/
171.1(14)8) and CꢁCPh (175.4(13)/176.2(15)8) groups show
the expected almost linear arrangement. As in 2, the Xyl
ring is coplanar with the Pt coordination plane, but the Ph
ring of CꢁCPh forms a dihedral angle of 30.528. The mole-
cules are arranged as head-to-tail pairs by weak p···p inter-
actions (3.60(2) ꢀ) between the bzq ligands and the Xyl
rings of the corresponding isocyanides. The dimers form ex-
tended 1D chains by weak p···p interactions (ca. 3.5 ꢀ) be-
tween the bzq ligands and the CꢁE bonds of CꢁCPh and
CNXyl groups. No metallophilic contacts are observed; the
platinum atoms are separated by long distances (Pt····Pt
4.717(1), 4.809(1) ꢀ; Figure 4).
ꢀ
(angles formed by the C N lines and the normal to plane
are 908 1, 86.138 2) as is the CNR ligand (angles formed by
ꢀ
the C N lines and the normal to plane are 908 1, 88.968 2).
In complex 2 the Xyl ring is coplanar with the bzq and
with the platinum coordination plane; the interplanar angles
are 0.698 and 2.108 respectively. The isolated complexes in
1 and 2 are quite similar but differ in the packing arrange-
ment. In complex 1, the complex units 1(A) and 1(B) are ar-
ranged in a head-to-head fashion and stacked in a columnar
way along the b axis through both significant p···p (the
shortest atomic separation between two neighboring bzq
units is 3.362 ꢀ, below the upper limit of 3.8 ꢀ for this kind
of interaction in aromatic compounds[21]) and metallophilic
Pt···Pt interactions (equivalent Pt···Pt···Pt angles of 161.458
and Pt···Pt distances of 3.371(1) ꢀ, shorter than the accepted
upper limit of 3.5 ꢀ for these kinds of interactions[6]). The
platinum coordination planes are parallel and lie staggered
(torsion angle N-Pt-Pt-Cbzq 23.8(2)8), presumably to mini-
mize repulsions and optimize the Pt···Pt and p···p interac-
tions. By contrast, in complex 2, the molecules are arranged
in head-to-tail pairs linked by short Pt···Pt (3.370(1) ꢀ) but
not p···p interactions. The dimers are packed in the crystal
forming extended 1D chains, but separated by longer distan-
ces (Pt···Pt 4.697(1) ꢀ).
Comparison of the crystal structures of the cyanide com-
pounds 1 and 2 with those of their chloro isocyanide coun-
terparts reveals that 1 shows a 1D crystal packing with sig-
nificant Pt···Pt (3.371 (1) ꢀ) and p···p interactions (3.262 ꢀ),
similar to that observed for [PtACHTNUTRGENN(UG bzq)ClACHTUNTGREN(NUGN CNtBu)·CHCl3]1
(Pt···Pt 3.3547(2) ꢀ). In these cases, neither the electronic
effect of the p-acceptor cyanide nor the local geometry
around the Pt center significantly affects the crystal struc-
ture. However, in [Pt
are arranged in head-to-tail pairs with short Pt···Pt (3.370
(1) ꢀ) but not p···p interactions, while in [Pt(bzq)Cl-
ACHTUNGTREN(NUGN CNXyl)], a head-to-tail pairing with one molecule shifted
ACHUTGTNREN(UNG bzq)(CN)ACHTUNTGREN(NUGN CNXyl)] (2), the molecules
The molecular structure of [Pt
(bzq)
E
G
ACHTUNGTRENNUNG
Figure 4, Table 2) confirms that, as in the precursor, the
isomer generated has the isocyanide ligand trans to the N
atom of the bzq group, suggesting that the trans influence of
significantly to the side of the other leads to a short
(3.293(8) ꢀ) interplanar separation between bzq groups but
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Luminescent Benzoquinolate-Isocyanide Platinum(II) Complexes
no metallophilic interactions. Bearing in mind the nonbulky
nature of chloride and cyanide ligands, the metallophilic
contacts in 2 could be attributed, to some extent, to the elec-
tron-withdrawing character of the cyanide ligand. In com-
plex 4, in spite of the p-acid character of the acetylide
ligand, the expected metallophilic interactions were not ob-
served, but rather p···p interactions between bzq and Xyl
isocyanide charge transfer 1ML’CT (dp(Pt)!p*
ACHTUNGTRENNUNG(CNR))
transitions to the LE absorptions bands, if any, must be very
low in complexes 1–3, since these bands show no depend-
ence on the isocyanide substituent (see inset in Figure 5).
By contrast, the lowest energy absorption band in the al-
kynyl complex 4 is remarkably red-shifted with respect to
the related cyanide derivative 2 (423 nm 4 vs. 400 nm 2). By
analogy with other alkynyl cycloplatinate compounds,[30,35]
ꢀ
ꢀ
rings and the bzq group and the C C and C N triple bonds
of CꢁCPh and CꢁNXyl groups. Therefore, complex 4 is
another example in which the supramolecular structure
seems to be determined by a delicate balance of the overall
noncovalent intermolecular interactions.
1
this band can be assigned to a mixed MLCT and alkynyl to
bzq (L’’LCT) transition. The observed bathochromic shift of
this band in complex 4 in relation to 2 and the chloride pre-
cursor (412 nm) is consistent with the expected destabiliza-
tion of a platinum alkynyl based HOMO upon replacement
of the cyanide or chloride group by the more electron-rich
alkynyl ligand. In all complexes, the lowest energy absorp-
tion band obeys Beerꢁs law in the range from 5ꢇ10ꢀ5 m to
10ꢀ3 m (complexes 1, 2, 4) or from 5ꢇ10ꢀ4 m to 10ꢀ5 m (com-
plex 3), which suggests no ground-state aggregation within
these concentration ranges.
Photophysical Properties
Absorption Spectra
Complexes 1–3 show low solubility in common organic sol-
vents. The electronic absorption spectra of 1–4 were record-
ed in CH2Cl2 at low concentration (5ꢇ10ꢀ5 m, Figure 5) and
The solid diffuse reflectance UV/Vis spectrum of 4 shows
no differences with respect to that observed in CH2Cl2
(Figure 6, Table 3), in accord with the lack of Pt···Pt or
Figure 5. UV/Vis spectra of 1–4 in CH2Cl2 (5ꢇ10ꢀ5 m) at 298 K. The inset
shows the low-energy region.
Figure 6. Normalized absorption spectra calculated from the reflectance
diffuse spectra of 1–4 in the solid state at 298 K. The photographs show
compounds 1–3 in the solid state.
the data are summarized in Table 3. As can be seen in
Figure 5 they reveal several intense absorptions at lmax
values ranging from 225 to 325 nm (e>104 mꢀ1 cmꢀ1), which
can be considered to be mainly due to intra
li
U
bzq···bzq interactions. Something similar was observed for
the yellow compound 2, which showed no effect of the short
Pt···Pt (3.3703(2) ꢀ) distances in the dimers. By contrast,
the 1D extended orange compound 1 and the fuchsia com-
pound 3 show absorption bands centered at approximately
460 and 530 nm, respectively. This LE absorption band is re-
CNR) and metal-perturbed ligand transitions, most likely
1
1
with contributions from MLCT and LL’CT transitions (L=
bzq, L’=CNR), as determined by DFT calculations in the
(CNR)].[18]
analogous compounds [PtACTHNUTRGNENG(U bzq)ClHCATUNGTRENNGUN
The less intense low-energy (LE) absorptions, which are
slightly blue-shifted (l>325–400 nm) in relation to the pre-
1
sponsible for their colors and may be ascribed to MMLCT
cursors [Pt
G
N
(ds*(Pt)!s
ACHTUNGTRENNUNG
2-Np 414 nm), are ascribed to a mixture of spin-allowed
meric” (s*
(p,bzq)!s
ACHTUNGTRENNUNG
metal-to-ligand charge transfer 1MLCT (dp(Pt)!p*
(bzq))
in other square-planar platinum(II) complexes containing
Pt···Pt and p···p interactions.
1
acidic cyanide group. Contributions of LL’CT or metal-to-
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Juan Forniꢂs, Violeta Sicilia et al.
FULL PAPER
Table 3. Absorption and emission data for compounds 1–4.
and S2 in the Supporting Infor-
mation) that, only for 2, ap-
pears together with two weak
bands at 482 and 512 nm when
lexc =400 nm. The emission ef-
ficiency follows the trend 2>
1>3 (f=57.6% (2), 42.1%
(1); inset in Figure S1 in the
Compound
labsorption [nm] (103 e [mꢀ1 cmꢀ1])
lem (lexc) [nm]
[f [%]]
t [ms]
1
solid, 298 K
solid, 77 K
232, 298, 398, 460 sh tail to 540
639 (400–450)
[42.1]
660 (450)
720 (550)
0.4 (58%), 1.4 (42%)
(639)
0.1 (24%), 2.3 (76%)
(660);
1.8 (720)
0.5 (576)
CH2Cl2 10ꢀ3 m,
298 K
576 max, 670 sh
(400)
484, 500, 518, 566
(400)
Supporting
Information).
CH2Cl2
236 (51.2), 290 sh (18.3), 300
(21.0), 342 (3.2), 386 (2.7), 400
(2.8)
Upon cooling at 77 K, 1 and 2
exhibit site-selective emission.
Thus, the emission band in 1 at
298 K splits into two structure-
less symmetric bands at
660 nm and 720 nm, which can
be selectively obtained upon
excitation at 450 and 550 nm,
respectively (Figure 7).
5ꢇ10ꢀ5 m,
298 K[a]
CH2Cl2 10ꢀ3 m,
77 K
535, 594, 653,
718 max (400)
650, 725 max (500)
730 (550)
482, 512, 662 max
(400) [57.6]
1.2 (730)
2
solid, 298 K
solid, 77 K
308, 405 tail to 500
25.4 (482); 20.8 (89%),
97.3 (11%) (512); 2.4
(662)
662 (470)
500, 509, 549 max, 80.1 (31%), 265.4 (69%)
582 sh, 680 sh
(400)
(500);
The excitation spectra moni-
tored at the two emission
maxima differ by 0.22 eV,
which suggest that each emis-
sion band corresponds to a dif-
ferent emissive state. The pres-
ence of two close emissive
states is a common phenomen-
on in platinum(II) complexes
containing p-extended ligands,
which undergo p···p and/or
Pt···Pt stacking. In view of the
observed Pt···Pt and p···p con-
tacts in its crystal structure and
recent calculations, these emis-
sions are assigned to mixed
3pp*/3MMLCT transitions, the
low-energy one having a pre-
120.5 (64%), 310.6
(36%) (509);
13.7 (75%), 213.9 (25%)
(549);
715 (500)
0.7 (715)
CH2Cl210ꢀ3 m,
298 K
475 sh, 583, 645 sh, 0.4 (475); 0.4 (575); 1.5
690 max (400)
(645); 1.2 (690)
CH2Cl2
236 (47.9), 304 (23.2), 386 (2.4), 482, 510 sh,
400 (2.4)
5ꢇ10ꢀ5 m,
298 K[a]
575 max (400)
CH2Cl2 10ꢀ3 m,
77 K
650 sh, 750 max
(400–475)
750 (520)
679 (400–550)
745 (400–550)
570, 698 (400)
2.9 (650)
3.6 (750)
3
4
solid, 298 K
solid, 77 K
CH2Cl2
246, 306, 395, 530 tail to 600
0.1
1.3
238 (82.2), 290 sh (29.0), 304
(32.1), 384 (3.1), 400 (3.1)
5ꢇ10ꢀ5 m,
298 K[a]
CH2Cl2
752 (500)
778 (550)
5ꢇ10ꢀ4 m,
77 K
dominant
(ds*(M)2!p*
and probably some 3MMCT3-
3MMLCT3-
ACHTUNGTREN(NGNU bzq)) character
solid, 298 K
257, 347, 426, 466 sh
480, 505, 517,
580 max (400)
[13.3]
12.1 (505);
9.8 (13%), 3.0 (87%)
(580)
A
solid, 77 K
500 max, 513, 542, 193 (500)
587 sh (400)
490 max, 550 (400)
N
CH2Cl2
237
348
N
R
5ꢇ10ꢀ5 m,
298 K[a]
CH2Cl2 10ꢀ3 m,
77 K
E
ACHTUNGTRENNUNG
490, 525, 570 max
(400)
490 max, 525, 570
(400)
CH2Cl2
5ꢇ10ꢀ5 m,
77 K
[a] The emission pattern was identical to that observed at a concentration of 5ꢇ10ꢀ4 m.
Emission Spectra
As expected, the excitation spectra for these two emis-
sions are quite different; the green emission can be attribut-
Complexes 1–4 are photoluminescent both at room and low
temperature (77 K) in the solid state and in CH2Cl2 solution
(Table 3). In the solid state at 298 K, powdered samples of
1–3 show broad structureless bands with maxima at 639 (1),
662 (2), and 679 nm (3; Figure 7 and Figure 8 and Figures S1
ed to excited states of the monomer species, mostly LC and
3MLCT, while the red-shifted band (715 nm) can be assigned
3
to MMLCT excited states in emissive aggregates. The weak
band of 3 becomes narrower and shifts to the red (745 nm)
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Luminescent Benzoquinolate-Isocyanide Platinum(II) Complexes
Figure 9. Normalized excitation and emission spectra of 1 (10ꢀ3 m), 2
(10ꢀ3 m), and 3 (5ꢇ10ꢀ4 m) at 298 K in CH2Cl2.
Figure 7. Normalized excitation and emission spectra of 1 in the solid
state at 298 and 77 K.
For compounds 1 and 2 the intensity of the emission band
decreases as the concentration decreases from 10ꢀ3 m to 5ꢇ
10ꢀ4 m, and the band shape also changes (see Figures S3 and
S4 in the Supporting Information for 1 and 2 respectively),
with the excimeric emission becoming less important as the
concentration decreases. For compound 3, study of the emis-
sion at different concentrations is precluded due to its
scarce solubility.
The emission profiles of 1–3 change dramatically in rigid
matrix of CH2Cl2 (77 K, Figure 10). In all cases an intense
3
low-energy MMLCT emission (l=730 (1), 750 (2), 778 nm
Figure 8. Normalized excitation and emission spectra of 2 in the solid
state at 298 and 77 K.
at 77 K (Figure S2 in the Supporting Information), as ex-
pected for an emission due to 3MMLCT/3pp* transitions
with predominant 3MMLCT contribution, associated with
aggregates with relatively strong Pt···Pt and p···p interac-
tions.[18,22–23,36b–d,37a]
Figure 10. Normalized excitation and emission spectra of 1 (10ꢀ3 m), 2
(10ꢀ3 m), and 3 (5ꢇ10ꢀ4 m) at 77 K in rigid matrix of CH2Cl2.
A concentrated solution of 1 (10ꢀ3 m) in CH2Cl2 at 298 K
displays a broad band from 450 to 750 nm with its maximum
at 576 nm (Figure 9). The excitation spectra monitored at
different frequencies resemble its absorption spectrum, indi-
cating that the emission is mainly due to monomer species
and excimers formed by interaction (p···p and/or Pt···Pt) of
an excited molecule with an adjacent ground-state one. Sol-
utions of 2 (10ꢀ3 m) and 3 (5ꢇ10ꢀ4 m) in CH2Cl2 show analo-
gous behavior, but in these complexes a more important
contribution associated with excimers of relatively low
energy is clearly observed.
(3)) can be obtained upon excitation at l=550 (1), 520 (2),
550 nm (3). The corresponding excitation spectra monitored
in these maxima indicate that these emissions are mainly
due to ground-state aggregates formed through Pt···Pt and/
or p···p stacking interactions.
For complexes 1 and 3, both the emission and the excita-
tion spectra in rigid matrix of CH2Cl2 (77 K) resemble those
observed in the solid state at 77 K. However, for complex 2
the green emission (ca. 500–600 nm) observed in the solid
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Juan Forniꢂs, Violeta Sicilia et al.
FULL PAPER
state upon excitation at 400 nm was not observed in rigid
matrix of CH2Cl2, and the LE band is notably red-shifted
(750 nm, glassy CH2Cl2 vs. 715 nm, solid 77 K). This feature
may be associated with the formation of aggregates with
a closer proximity in the glass than in the solid state.
the cyanide seems to strengthen the Pt···Pt interactions in
such a way that the phosphorescent emission of compounds
1–3 in rigid media (solid or rigid matrix in CH2Cl2) has a pre-
dominant 3MMLCT
A
ACHTUNGERTN(NUNG bzq)) character. Howev-
er, in complex 4, in spite of the p-acid character of the al-
kynyl ligand, no metallophilic interactions are present, and
therefore, its luminescence behavior resembles that of the
Powdered samples of the alkynyl isocyanide complex 4
exhibit a high-energy (HE) structured band (480, 505,
517 nm) at 298 K, which is ascribed to a typical mixed
3LC/3MLCT transition of the monomer species, together
(CNXyl)].[18]
related chloro derivative [PtACTHNUGTRENNUG(bzq)ClCAHTUNGTRENNUGN
3
with LE emission of pp* excimeric nature with its maxi-
mum at 580 nm (Figure 11). In keeping with this notion, the
excitation spectra monitored at 505 and at 580 nm are essen-
tially coincident. The quantum yield (13.3%) is considerably
lower than in 1 and 2.
Conclusions
Compounds [Pt
Np (3)) and [Pt
tained from the corresponding chloro isocyanide derivatives
[Pt(bzq)Cl(CNR)]. The isolated cyanide compounds show
a trans-Cbzq,CNR configuration in contrast to a trans-
bzq,CNR observed for complex 4 and the starting chloro
compounds. A more efficient and selective way to obtain 1–
3 is by reaction of [Pt(bzq)(CNR)2]ClO4 (R=tBu, Xyl, 2-
G
ACHTUNGTRENNUNG
E
E
ACHTUNGTRENNUNG
G
ACHTUNGTRENNUNG
N
A
ACHTUNGTRENNUNG
Np) with equimolar amount of KCN.
X-ray studies on single crystals reveal that 1 shows a col-
umnar-stacked chain structure with significant Pt···Pt
(3.371(1) ꢀ) and p···p (3.262 ꢀ) interactions. These interac-
tions are similar to those observed for the precursor [Pt-
ACHUTNGERN(NUG bzq)ClAHCTUNGTREN(NUNG CNtBu)·CHCl3]1, suggesting that in this case nei-
ther the electronic effect of the p-acceptor cyanide ligand
nor the local geometry around the Pt center have a signifi-
cant effect on the crystal structure. However, in [Pt-
A
ACHTUNGTRENUN(NG CNXyl)] (2), the molecules are arranged in
Figure 11. Normalized excitation and emission spectra of 4 in the solid
state at 298 K and 77 K.
A
ACHTUNGTRENNUNG
which displayed p···p (3.293(8) ꢀ, bzq···bzq) interactions,
but not metallophilic interactions. In this case the metallo-
philic contacts in 2 could be attributed to the electron-with-
drawing character of the cyanide ligand. However, in spite
of the presence of the p-acidic acetylide ligand, no metallo-
philic interactions were observed in related complex 4, and
its solid structure is mainly determined by a subtle balance
of different (bzq···Xyl/CꢁC/CꢁN) interactions between
molecules.
Lifetime measurement in the maximum (580 nm) fit to
two components (t=9.8 ms (13%), 3.0 ms (87%)), the long
component (dominant in the high-energy peaks 12.1 ms
3
(505 nm)) is attributed mainly to the structured LC emis-
sion, whereas the short component is attributed to excimeric
3pp* emission. Upon cooling to 77 K, the LE band almost
disappears, and only the structured HE emission, with lmax
=
500 nm, is observed (Figure 11). The long lifetime (193 ms),
which fits well to monoexponential decay, is indicative of
emission with primarily LC parentage. Both in diluted (5ꢇ
Pt···Pt and/or p···p contacts present in the cyanide deriva-
tives (1–3) affect their emission properties in rigid media
showing, in the solid state and in glasses, characteristic
3
10ꢀ5 m) and concentrated (10ꢀ3 m) deaereated CH2Cl2 solu-
tions at room temperature, this complex only exhibits the
structured emission profile of the monomer (lmax 490 nm).
At 77 K an additional excimeric feature located at 570 nm is
also observed, the intensity of which clearly increases with
concentration (Figures S5 and S6 in the Supporting Informa-
tion).
3
3MMLCT and/or pp* excimeric low-energy features. How-
ever, in liquid CH2Cl2 the emissions are due to monomer
and excimer species, with the excimeric emission becoming
more important as the concentration increases. In agree-
ment with the crystal packing, the alkynyl isocyanide com-
plex 4 does not show low-energy 3MMLCT features. This
complex displays a typical emission of the monomer species
and it is only at 298 K in solid state or in rigid matrix of
CH2Cl2 at 77 K that an additional low-energy emission of
3pp* excimeric nature is also observed.
The bright luminescence of 1 and 2 at 298 K in the solid
state at 298 K contrasts with the weak or nonluminescence
of the related chloro isocyanide compounds. This fact can be
related to the stronger-field nature of the cyanide compared
to chloride, which increases the energy gap DE between the
lowest-lying excited state and the higher-lying nonradiative
d–d state. In addition, the electron-withdrawing character of
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Luminescent Benzoquinolate-Isocyanide Platinum(II) Complexes
CH3); 1H NMR (400.13 MHz, CD2Cl2, 258C, TMS): d=8.88 (dd, 3J-
(H2,H3)=5 Hz, 4J(H2,H4)=1 Hz, 3J(H2,Pt)=31 Hz, 1H; bzq-H2), 8.42
(dd, 3J(H4,H3)=8 Hz, 1H; bzq-H4), 8.27 (dd, 4J(H9,H7)=1 Hz, 3J-
(H9,H8)=7 Hz, 3J(H9,Pt)=51 Hz, 1H; bzq-H9) 7.81 (AB, 3J(H5,H6)=
9 Hz, 1H; bzq-H5), 7.67 (dd, 3J(H7,H8)=8 Hz, 1H; bzq-H7), 7.61 (dd,
1H; bzq-H8), 7.59 (AB, 1H; bzq-H6), 7.53 ppm (dd, 1H; bzq-H3); 13C{1H}
Experimental Section
G
R
ACHTUNGTRENNUNG
G
ACHTUNGTRENNUNG
General Procedures and Materials
R
G
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
[31a]
The starting materials [Pt
G
G
(CNR)][18]
and [PtACTHNGUTREN(UNG bzq)ClACTHUNGTRENNUNG
(R=tert-butyl, 2,6-dimethylphenyl, 2-naphtyl) were prepared as de-
scribed elsewhere. K13CN and KCN were used as purchased from Isotec.
Elemental analyses were carried out with a EuroEa or CE Instrument
EA1110 elemental analyzers. IR spectra were recorded on a Perkin–
Elmer Spectrum 100 or on a Nicolet Nexus FTIR spectrometer (ATR in
the range 250–4000 cmꢀ1). Mass spectra analyses were performed with
NMR (1’, 100.6 MHz, CD2Cl2, 258C, TMS): d=111.1 ppm (s, 1J
ACHTUNGTRENNUNG(C,Pt)=
1429 Hz; 13CNtransꢀN,); IR: n˜ =2209 (s, CꢁN-tBu), 2188 (s), 2123 cmꢀ1 (s,
CꢁNꢀ); MS (ES+): m/z (%): 482.9 (100) [M+]; elemental analysis calcd
(%) for C19H17N3Pt: C 47.30, H 3.55, N 8.71; found: C 47.28, H 3.48, N
8.69.
a
Microflex MALDI-TOF Bruker or an Autoflex III MALDI-TOF
Synthesis of (SP-4–3)-[Pt
ACHUTGTNRENN(GU bzq)(CN)HCATUNGTREN(NNGU CN-Xyl)] (2)
Bruker instrument. NMR spectra were recorded on a Varian Unity-300
and a Bruker AV-400 spectrometer using the standard reference SiMe4
(TMS) for 1H and 13C. All of the 13C spectra were proton-decoupled, J is
given in Hz, and assignments are based on 1H–1H COSY experiments.
The NMR spectral assignments follow the numbering in Scheme 2.
Method a) KCN (0.017 g, 0.27 mmol) and MeOH (10 mL) were added to
a solution of [Pt(bzq)(CN-Xyl)2]ClO4 (0.183 g, 0.25 mmol) in CH2Cl2
A
ACHTUNGTRENNUNG
(8 mL), and the mixture was stirred. The initially yellow solution turned
orange, and after 15 min a yellow solid precipitated. The solvent was
evaporated to dryness, CH2Cl2 (65 mL) was added to the residue, and the
suspension was filtered. The resulting solution was evaporated to ca.
2 mL to give a yellow solid 2 that was filtered and washed with Et2O
(5 mL). Yield: 0.120 g, 91%. Method b) AgClO4 (0.062 g, 0.29 mmol) was
added to a solution of [PtACTHUNTGRNENUG(bzq)ClHCATUNGTRENN(UGN CN-Xyl)] (0.162 g, 0.30 mmol) in di-
cloromethane/acetone (25/2 mL) at 08C. The mixture was stirred for 1 h
and it was then filtered through Celite. KCN (0.019 g, 0.29 mmol) and
MeOH (2 mL) were added to the resulting solution; the mixture was
stirred for one hour at 08C and then left to reach RT. It was then evapo-
rated to dryness, the residue was treated with CH2Cl2 (10 mL), and the
mixture was filtered through Celite. The evaporation of the solvent to
2 mL caused the precipitation of complex 2 as a yellow solid. Yield:
0.077, 48%. 1H NMR (400.13 MHz, CD2Cl2, 258C, TMS): d=9.13 (d, 3J-
Scheme 2. Numbering for NMR spectral assignment.
Diffuse reflectance UV/Vis (DRUV) spectra were recorded on a Thermo
Electron Corporation Evolution 600 or on a Shimadzu UV-3600 spectro-
photometers equipped with a Praying Mantis integrating sphere. The
solid samples were homogeneously diluted with silica. The absorption
spectra were obtained using the Kubelka–Munk transformation of the re-
flectance spectra. Steady-state photoluminescence spectra were recorded
on a Jobin–Yvon Horiba Fluorolog FL-3–11 Tau 3 spectrofluorimeter
using band pathways of 3 nm for both excitation and emission. Phosphor-
escence lifetimes were recorded with a Fluoromax phosphorimeter acces-
sory containing a UV xenon flash tube with a flash rate between 0.05 and
25 Hz. Phase shift and modulation were recorded over the frequency
range of 0.1–100 MHz. Nanosecond lifetimes were recorded with an IBH
5000F coaxial nanosecond flashlamp. Quantum yields in the solid state
were measured upon excitation at 400 nm (2, 4), 450 nm (1), using an F-
3018 Integrating Sphere mounted on a Fluorolog FL-3-11-Tau3 spectro-
fluorimeter. Data were fitted using the Jobin–Yvon software package
and the Origin 7.5 program.
A
U
(H4,H3)=8 Hz,
ACHTUNGTRENNUNG
A
ACHTUNGTRENNUNG
AHCTUNGTRENNUNG
ACTHNUTRGNEUNG
7.65 (AB, 1H; bzq-H6), 7.59 (dd, 1H; bzq-H3), 7.39 (t, 3J(H3,H4,H5)=
8 Hz, 1H; CNXyl-H4), 7.26 (d, 2H; CNXyl-H3,H5) 2.64 ppm (s, 6H;
CNXyl-CH3); 13C{1H} NMR (2’, 100.6 MHz, CD2Cl2, 258C, TMS): d=
1
110.5 ppm (s, J
U
2131 cmꢀ1 (s, CꢁNꢀ). MS (ES+): m/z (%): 531.0 (100) [M+]; elemental
analysis calcd (%) for C23H17N3Pt: C 52.07, H 3.23, N 7.92. Found: C
52.20, H 3.40, N 7.65.
Synthesis of (SP-4–3)-[Pt
ACHUTGTNRENN(GU bzq)(CN)AHCTUNGTREN(NNGU CN-2-Np)] (3):
Method a) KCN (0.0158 g, 0.24 mmol) and MeOH (25 mL) were added
to a solution of [Pt(bzq)(CN-2-Np)2]ClO4 (0.189 g, 0.24 mmol) in CH2Cl2
A
ACHTUNGTRENNUNG
(35 mL) and the mixture was stirred. The initially yellow solution turned
red, and after 50 min the solvent was evaporated to dryness. CH2Cl2
(200 mL) was added to the residue, and the suspension was filtered.
Evaporation of the resulting solution to dryness gave a fuchsia solid 3
that was filtered and washed with Et2O (30 mL). Yield: 0.114 g, 85%.
Method b) AgClO4 (0.082 g, 0.39 mmol) was added to a solution of [Pt-
Synthesis of (SP-4-3)-[Pt
ACHTUNGTRENNUNG(bzq)(CN)HCATUNGTREN(NNGU CN-tBu)] (1)
Method a) KCN (0.015 g, 0.23 mmol) and MeOH (30 mL) were added to
a solution of [Pt(bzq)(CN-tBu)2]ClO4 (0.148 g, 0.23 mmol) in CH2Cl2
A
ACHTUNGTRENNUNG
(9 mL) and the mixture was stirred for 40 min. The bright yellow solution
was then evaporated to dryness and CH2Cl2 (65 mL) was added to the
residue. Subsequently, the mixture was filtered, the solution was evapo-
rated to dryness, and the orange solid 1 was filtered and washed with
Et2O (5 mL). Yield: 0.080 g, 75%. Method b) AgClO4 (0.062 g,
ACHUTNGRENU(NG bzq)ClHCATUNGTRENN(UGN CN-2-Np)] (0.223 g, 0.39 mmol) in acetonitrile (30 mL) at room
temperature, and the mixture was stirred for 15 min. The solution was fil-
tered through Celite, and KCN (0.026 g, 0.39 mmol) and MeOH (4 mL)
were added to the resulting solution. After one hour the solvent was
evaporated to dryness and the residue was washed with water (2ꢇ
10 mL). It was then treated with acetone (20 mL) and heated at refluxed
for 45 min. The precipitated fuchsia solid 3 was filtered from the hot mix-
0.30 mmol) was added to a solution of [PtACTHNUTRGENN(UG bzq)ClAHCTUNGTRNEN(UGN CN-tBu)] (0.148 g,
0.30 mmol) in dicloromethane/acetone (25/2 mL) at 08C and the mixture
was stirred for one hour. It was then filtered through Celite, and KCN
(0.020 g, 0.30 mmol), MeOH (2 mL) and H2O (3 mL) were added to the
resulting solution. The mixture was stirred for 1 hour at 08C and 1 hour
at room temperature. Subsequently, MgSO4 was added and the mixture
was stirred for a while and then filtered through Celite. The solution was
evaporated to dryness and the orange residue was treated with CH2Cl2
(5 mL). The red solid, 1, was filtered and dried. Yield: 0.077 g, 48%.
1H NMR (400.13 MHz, [D6]acetone, 258C, TMS): d=9.05 (dd, 3J-
1
ture. Yield: 0.145, 67%. H NMR (400.13 MHz, CD2Cl2, 258C, TMS): d=
9.07 (dd, 3J(H2,H3)=5 Hz, 4J(H2,H4)=1 Hz, 3J(H2,Pt)=31 Hz, 1H; bzq-
ACHTUNGTRNENNUG ACHTNUGTRENNUNG ACTHNUGTRENNGUN
H2), 8.39 (dd, 3J(H4,H3)=8 Hz, 1H; bzq-H4), 8.28 (dd, 4J(H9,H7)=1 Hz,
ACTHNUTRGENNUG CAHTUNGTRENNUGN
3
3J(H9,H8)=7 Hz, J(H9,Pt)=51 Hz, 1H; bzq-H9), 8.21 (s, 1H; CNNp-H1),
ACTHNUTRGENNUG CAHTUNGTRENNUGN
7.75 ppm (m, 11H; bzq-H3, bzq-H5, bzq-H6, bzq-H7, bzq-H8, CNNp-H3,
CNNp-H4, CNNp-H5, CNNp-H6, CNNp-H7, CNNp-H8). 13C{1H} NMR
(3’, 75.43 MHz, CD2Cl2, 258C, TMS): d=110.4 ppm (s, 1J
ACHTUNGTRENNUNG(C,Pt)=
1426 Hz; 13CNtransꢀN,); IR: n˜ =2181 (s, CꢁN-2-Np), 2131 cmꢀ1 (s, CꢁNꢀ);
MS (ES+): m/z (%): 553.0 (60) [M+]; elemental analysis calcd (%) for
C25H15N3Pt: C 54.35, H 2.74, N 7.61. Found: C 54.53, H 2.67, N 7.50.
A
R
ACHTUNGTRENNUNG
A
U
ACHTUNGTRENNUNG
7 Hz, 3J
ACHTUNGTRENNUNG
A
3J
3J
N
ACHTUNGTRENNUNG
Chem. Asian J. 2012, 00, 0 – 0
ꢅ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
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Juan Forniꢂs, Violeta Sicilia et al.
FULL PAPER
Synthesis of (SP-4–2)-[Pt
(bzq)
E
G
and the diffraction frames were integrated and corrected for absorption
using the Crysalis RED package.[38] For 4, X-ray intensity data were col-
lected with a Nonius k-CCD area-detector diffractometer using graphite-
monocromated Mo Ka radiation. Images were processed using the
DENZO and SCALEPACK suite of programs,[39] and the absorption cor-
rection was performed using XABS2.[40] The structures were solved by
Patterson and Fourier methods and refined by full-matrix least squares
on F2 with SHELXL-97.[41] All non-hydrogen atoms were assigned aniso-
tropic displacement parameters and refined without positional con-
straints. All hydrogen atoms were constrained to idealized geometries
and assigned isotropic displacement parameters equal to 1.2 times the
Uiso values of their attached parent atoms (1.5 times for the methyl hy-
drogen atoms). Full-matrix least-squares refinement of these models
against F2 converged to final residual indices given in Table 4.
HCꢁCPh (31 mL, 0.28 mmol), CuI (6.5 mg, 0.03 mmol), and NEt3 (1 mL)
were added to yellow solution of [Pt(bzq)Cl(CN-Xyl)] (0.100 g,
a
0.18 mmol) in deoxygenated CHCl3 (15 mL) under Ar. After 1 h of stir-
ring, the solvent was evaporated to dryness and the residue was treated
with 2-propanol (15 mL), giving a yellow solid 4. Yield: 0.098 g, 88%.
1H NMR (400.13 MHz, CDCl3, 258C, TMS): d=10.03 (d, 3J
ACHTUNGTRENNUNG
5 Hz, 3J
H4), 8.06 (d, 3J
ACHTUNGTRENNUNG
3J(H5,H6)=9 Hz, 1H; bzq-H5), 7.68 (AB, 1H; bzq-H6), 7.58 (m, 3H; bzq-
G
N
H3, bzq-H7, bzq-H8), 7.26 (m, 3H; CNXyl-H3,H4,H5), 2.66 ppm (s, 6H;
CNXyl-CH3). 13C{1H} NMR (100.6 MHz, CDCl3, 258C, TMS): d=159.1
(s, 1J
(s, 2J
(Pt-C)=21, 1C, bzq), 138.6–121.5 (8C bzq and aromatics), 118.3 (s, 1J-
ACHTUNGTRENNUNG ACHTUNGTRENNUGN
(C-Pt)=712 Hz; bzq-C10), 158.1 (s, 2J(C-Pt)=61 Hz, bzq-C12), 151.4
ACHTUNGTRENNUNG ACHTUNGTREN(NGUN C-Pt)=23 Hz, 1C, bzq), 143.0 (s,
(C-Pt)=41 Hz; bzq-C2), 148.0 (s, J
JACHTUNGTRENNUNG
A
U
Cb, Cb trans to Corthomet), 19.0 ppm (s; Xyl-CH3); IR: n˜ =2178 (s, CꢁN-
Xyl), 2167 (s), 2119 cmꢀ1 (s, CꢁC); MS (MALDI-TOF+): m/z (%):
605.3 (50) [M+], 1210.6 (40) [2M]+, elemental analysis calcd (%) for
C30H22N2Pt: C 59.50, H 3.66, N 4.63. Found: C 58.97, H 3.84, N 4.47.
Acknowledgements
This work was supported by the Spanish MICINN [Projects CTQ2008-
06669-C02-01,02 and the Gobierno de Aragꢆn (Grupo Consolidado: Quꢃ-
mica Inorgꢄnica y de los Compuestos Organometꢄlicos). P.B. and A.D.
acknowledge the support of a FPI grant from the MICINN.
X-ray Structure Determination
Crystal data and other details of the structure analysis are presented in
Table 4. Suitable crystals for X-ray diffraction studies were obtained by
slow diffusion of n-hexane into concentrated solutions of the complexes
in CHCl3 at 48C (1 and 2) ꢀ308C (4). The crystals were mounted at the
end of a quartz fiber. The radiation used was graphite monochromated
MoKa (l=0.71073 ꢀ). For 1·CHCl3 and 2·CHCl3, X-ray intensity data
were collected on an Oxford Diffraction Xcalibur CCD diffractometer,
[1] B. M. Anderson, S. K. Hurst, Eur. J. Inorg. Chem. 2009, 3041–3054.
[2] M. Atoji, J. W. Richardson, R. E. Rundle, J. Am. Chem. Soc. 1957,
79, 3017–3020.
[3] a) J. R. Miller, J. Chem. Soc. 1961, 4452–4457; b) J. Bremi, D. Bro-
velli, W. Caseri, G. Hꢈhner, P. Smith, T. Tervoort, Chem. Mater.
1999, 11, 977–994.
[4] a) S. M. Drew, D. E. Janzen, K. R. Mann, Anal. Chem. 2002, 74,
2547–2555; b) S. M. Drew, D. e. Janzen, C. E. Buss, D. I. MacEwan,
K. M. Dublꢃn, K. R. Mann, J. Am. Chem. Soc. 2001, 123, 8414–8415.
[5] S. M. Drew, J. E. Mann, B. J. Marquardt, K. R. Mann, Sens. Actua-
tors B 2004, 97, 307–312.
[6] L. H. Doerrer, Dalton Trans. 2010, 39, 3543–3553.
[7] G. Gliemann, H. Yersin, Structure and Bonding, Springer, Berlin,
1985.
[8] T. J. Wadas, Q.-M. Wang, Y.-J. Kim, C. Flashenreim, T. M. Blanton,
R. Eisenberg, J. Am. Chem. Soc. 2004, 126, 16841–16849.
[9] V. W. W. Yam, K. M. C. Wong, N. Zhu, J. Am. Chem. Soc. 2002, 124,
6506–6507.
[10] V. W. W. Yam, K. H. Y. Chan, K. M. C. Wong, N. Zhu, Chem. Eur. J.
2005, 11, 4535–4543.
[11] J. A. Bailey, M. G. Hill, R. E. Marsh, V. M. Miskowski, W. P. Schae-
fer, H. B. Gray, Inorg. Chem. 1995, 34, 4591–4599.
[12] a) R. J. Osborn, D. Rogers, J. Chem. Soc. Dalton Trans. 1974, 1002–
1004; b) W. B. Connick, L. M. Henling, R. E. Marsh, H. B. Gray,
Inorg. Chem. 1996, 35, 6261–6265.
[13] a) W. B. Connick, L. M. Henling, R. E. Marsh, Acta Crystallogr. Sect.
B 1996, 52, 817–822; b) M. Kato, C. Kosuge, K. Morii, J. S. Ahn, H.
Kitagawa, T. Mitani, M. Matsushita, T. Kato, S. Yano, M. Kimura,
Inorg. Chem. 1999, 38, 1638–1641.
[14] W. B. Connick, R. E. Marsh, W. P. Schaefer, H. B. Gray, Inorg.
Chem. 1997, 36, 913–922.
[15] C. E. Buss, K. R. Mann, J. Am. Chem. Soc. 2002, 124, 1031–1039.
[16] A. G. Dylla, D. E. Janzen, M. K. Pomije, K. R. Mann, Organometal-
lics 2007, 26, 6243–6247.
[17] Y. Sun, K. Ye, H. Zhang, J. Zhang, L. Zhao, B. Li, G. Yang, B. Yang,
Y. Wang, S. W. Lai, C. M. Che, Angew. Chem. 2006, 118, 5738–5741;
Angew. Chem. Int. Ed. 2006, 45, 5610–5613.
[18] A. Dꢃez, J. Fornies, C. Larraz, E. Lalinde, J. A. Lꢆpez, A. Martin,
M. T. Moreno, V. Sicilia, Inorg. Chem. 2010, 49, 3239–3259.
[19] a) I. Eryazici, C. N. Moorefield, G. R. Newkome, Chem. Rev. 2008,
108, 1834–1895; b) J. Moussa, K. M. C. Wong, L. M. Chamoreau, H.
Amouri, V. W. W. Yam, Dalton Trans. 2007, 3526–3530.
[20] S. Y. L. Leung, A. Y. Y. Tam, C. H. Tao, H. S. Chow, V. W. W. Yam,
J. Am. Chem. Soc. 2012, 134, 1047–1056.
Table 4. Crystal data and structure refinement for complexes 1·CHCl3,
2·CHCl3 and 4.
1·CHCl3
2·CHCl3
4
formula
Mt [gmolꢀ1
T [K]
C19H17N3Pt·CHCl3 C23H17N3Pt·CHCl3 C30H22N2Pt
]
601.81
100(1)
0.71073
orthorhombic
Pnma
649.85
100(1)
0.71073
triclinic
605.59
173(1)
0.71073
monoclinic
P21/c
l [ꢀ]
crystal system
space group
a [ꢀ]
b [ꢀ]
c [ꢀ]
¯
P1
25.8987(6)
6.6532(1)
23.9980(6)
90
90
90
7.3178(2)
10.2903(3)
15.2916(5)
93.787(2)
95.044(3)
103.757(2)
1109.62(6)
2
12.8868(13)
8.8689(9)
19.8272(16)
90
96.994(6)
90
a [8]
b [8]
g [8]
V [ꢀ3]
Z
4135.05(16)
8
2249.2(4)
4
1 [gcmꢀ3
]
1.933
1.945
1.788
m [mmꢀ1
(000)
2q range [8]
]
7.184
6.701
6.260
F
A
2304
624
1176
8.4–57.7
7.8–54.2
12627
5.0–51.4
4241
no. of reflns collect- 25140
ed
no. of unique reflns 5383
4817
4241
R
(int)
0.0259
0.0179
0.0000
final R indices
[I>2q(I)][a]
R1
wR2
0.0329
0.0674
0.0154
0.0411
0.0659
0.1360
R indices (all data)
R1
wR2
0.0432
0.0686
0.0165
0.0413
1.063
0.1309
0.1650
1.064
Goodness-of-fit on 1.281
F2[b]
2
2
[a] R1 =ꢀ(jFojꢀjFcj)/ꢀ jFo j. wR2 =[ꢀw (Fo ꢀFc2)2/ꢀw
(Fo )2
]
1/2. [b] Good-
2
ness-of-fit=[ꢀw (Fo ꢀFc2)2/(nobsꢀnparam)]1/2
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Luminescent Benzoquinolate-Isocyanide Platinum(II) Complexes
[21] C. Janiak, J. Chem. Soc. Dalton Trans. 2000, 3885–3896.
[22] M. Kato, Bull. Chem. Soc. Jpn. 2007, 80, 287–294.
[23] C. Po, A. Y. Y. Tam, K. M. C. Wong, V. W. W. Yam, J. Am. Chem.
Soc. 2011, 133, 12136–12143.
[33] a) S. W. Lai, H. W. Lam, W. Lu, K. K. Cheung, C. M. Che, Organo-
metallics 2002, 21, 226–234; b) J. Vicente, A. Arcas, J. M. Fernꢄn-
dez-Hernꢄndez, G. Aullꢆn, D. Bautista, Organometallics 2007, 26,
6155–6169; c) P. J. Martellaro, S. K. Hurst, R. Larson, E. H. Abbott,
E. S. Peterson, Inorg. Chim. Acta 2005, 358, 3377–3383.
[24] a) J. Ni, X. Zhang, Y. H. Wu, L. Y. Zhang, Z. N. Chen, Chem. Eur. J.
2011, 17, 1171–1183; b) X. Zhang, J. Y. Wang, J. Ni, L. Y. Zhang,
Z. N. Chen, Inorg. Chem. 2012, 51, 5569–5579; c) X. Zhang, B. Li,
Z. H. Chen, Z. N. Chen, J. Mater. Chem. 2012, 22, 11427–11441.
[25] a) C. L. Exstrom, J. R. Sowa, Jr., C. A. Daws, D. Janzen, K. R.
Mann, G. A. Moore, F. F. Stewart, Chem. Mater. 1995, 7, 15–17;
b) C. A. Daws, C. L. Exstrom, J. R. Sowa Jr., K. R. Mann, Chem.
Mater. 1997, 9, 363–368; c) Y. Kunugi, L. L. Miller, K. R. Mann,
M. K. Pomije, Chem. Mater. 1998, 10, 1487–1489; d) J. W. Grate,
L. K. Moore, D. E. Janzen, D. J. Veltkamp, S. Kaganove, S. M. Drew,
K. R. Mann, Chem. Mater. 2002, 14, 1058–1066; e) C. E. Buss, C. E.
Anderson, M. K. Pomije, C. M. Lutz, D. Britton, K. R. Mann, J. Am.
Chem. Soc. 1998, 120, 7783–7790.
[34] J. Fornies, S. Fuertes, J. A. Lꢆpez, A. Martꢃn, V. Sicilia, Inorg. Chem.
2008, 47, 7166–7176.
[35] a) P. H. Lanoꢉ, H. Le Bozec, J. A. G. Williams, J. L. Fillaut, V. Guer-
chais, Dalton Trans. 2010, 39, 707–710; b) R. Liu, Y. Li, H. Zhu, W.
Sun, J. Phys. Chem. A 2010, 114, 12639–12645; c) W. Lu, B. X. Mi,
M. C. W. Chan, Z. Hui, C. M. Che, N. Zhu, S. T. Lee, J. Am. Chem.
Soc. 2004, 126, 4958–4971.
[36] a) V. W. W. Yam, K. H. Y. Chan, K. M. C. Wong, B. W. K. Chu,
Angew. Chem. 2006, 118, 6315; Angew. Chem. Int. Ed. 2006, 45,
6169; b) C. K. Koo, K. L. Wong, K. C. Lau, W. Y. Wong, M. H. W.
Lam, Chem. Eur. J. 2009, 15, 7689–7697; c) K. M. C. Wong, V. W. W.
Yam, Acc. Chem. Res. 2011, 44, 424–434; d) V. Sicilia, J. Fornies,
J. M. Casas, A. Martꢃn, J. A. Lꢆpez, C. Larraz, P. Borja, C. Ovejero,
D. Tordera, H. Bolink, Inorg. Chem. 2012, 51, 3427–3435.
[37] a) C. T. Liao, H. H. Chen, H. F. Hsu, A. Poloek, H. H. Yeh, Y. Chi,
K. W. Wang, C. H. Lai, G. H. Lee, C. W. Shih, P. T. Chou, Chem.
Eur. J. 2011, 17, 546–556; b) X. Zhou, H. X. Zhang, Q. J. Pan, M. X.
Li, Y. Wang, C. M. Che, Eur. J. Inorg. Chem. 2007, 2181–2188.
[38] CrysAlis RED Program for X-ray CCD camera data reduction,
Oxford Difraction Ltd, Oxford, UK, 2005–2006.
[39] Z. Otwinowski, W. Minor in Methods in Enzymology, Vol. 276A
(Eds.: C. V. Carter, Jr., R. M. Sweet), Academic Press, New York,
1997, p. 307.
[40] S. Parkin, B. Moezzi, H. Hope, J. Appl. Crystallogr. 1995, 28, 53–56.
[41] G. M. Sheldrick, SHELXL-97 Program for Crystal Structure Deter-
mination, University of Gçttingen, Gçttingen, Germany, 1997.
[26] S. M. Drew, L. I. Smith, K. A. McGee, K. R. Mann, Chem. Mater.
2009, 21, 3117–3124.
[27] G. Aullꢆn, S. Alvarez, Chem. Eur. J. 1997, 3, 655–664.
[28] J. P. H. Charmant, J. Forniꢂs, J. Gꢆmez, E. Lalinde, R. I. Merino,
M. T. Moreno, G. Orpen, Organometallics 1999, 18, 3353–3358.
[29] J. Forniꢂs, S. Fuertes, C. Larraz, A. Martꢃn, V. Sicilia, A. C. Tsipis,
Organometallics 2012, 31, 2729–2740.
[30] S. Fernꢄndez, J. Forniꢂs, B. Gil, J. Gꢆmez, E. Lalinde, Dalton Trans.
2003, 822–830.
[31] a) A. Dꢃez, J. Forniꢂs, S. Fuertes, E. Lalinde, C. Larraz, J. A. Lꢆpez,
A. Martꢃn, M. T. Moreno, V. Sicilia, Organometallics 2009, 28, 1705;
b) A. Dꢃez, J. Forniꢂs, A. Garcꢃa, E. Lalinde, M. T. Moreno, Inorg.
Chem. 2005, 44, 2443–2453; c) J. Forniꢂs, S. Fuertes, A. Martꢃn, V.
Sicilia, B. Gil, E. Lalinde, Dalton Trans. 2009, 2224–2234.
[32] a) B.-H. Xia, C. M. Che, D. L. Phillips, K.-H. Leung, K. K. Cheung,
Inorg. Chem. 2002, 41, 3866–3875; b) M.-L. Flay, H. Vahrenkamp,
Eur. J. Inorg. Chem. 2003, 1719–1726; c) J. Forniꢂs, J. Gꢆmez, E. La-
linde, M. T. Moreno, Chem. Eur. J. 2004, 10, 888–898.
Received: June 29, 2012
Published online: && &&, 0000
Chem. Asian J. 2012, 00, 0 – 0
ꢅ 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
www.chemasianj.org
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FULL PAPER
Platinum Complexes
Shining bright: New benzoquinolate
isocyanide platinum(II) complexes,
including the bright luminescent com-
Juan Forniꢀs,* Violeta Sicilia,*
Pilar Borja, Josꢀ M. Casas,
pounds (SP-4-3)-[PtACTHNUGRTNENUG(bzq)(CN)ACHTUNGTRENNUNG(CNR)]
Alvaro Dꢁez, Elena Lalinde,
Carmen Larraz, Antonio Martꢁn,
(R=tBu (1), Xyl(2)), have been iso-
lated as pure isomers. The title weak
intermolecular interactions are respon-
sible for their photophysical proper-
ties.
M. Teresa Moreno
&&&& — &&&&
Luminescent Benzoquinolate-Isocya-
nide Platinum(II) Complexes: Effect
of Pt···Pt and p···p Interactions on
their Photophysical Properties
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ÝÝ These are not the final page numbers!