Racemic (RSC,SRS)-(2-{[1-allyl­oxy­carbonyl-3-(methyl­sulfanyl)prop­yl]iminometh­yl}phenyl-κ3S,N,C1)chlorido­platinum(II)

Isozaki, K.; Sato, A.; Miki, K.

doi:10.1107/S160053680904238X

metal-organic compounds

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ISSN: 2056-9890

Volume 65| Part 11| November 2009| Page m1401

https://doi.org/10.1107/S160053680904238X

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Racemic (RS_C,SR_S)-(2-{[1-allyloxycarbonyl-3-(methylsulfanyl)propyl]iminomethyl}phenyl-κ³S,N,C¹)chloridoplatinum(II)

Katsuhiro Isozaki,^a ^* Akira Sato ^b and Kazushi Miki ^a,^c

^aOrganic Nanomaterials Center, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan, ^bMaterials Analysis Center, National Institute for Materials Science, Tsukuba, Ibaraki 305-0044, Japan, and ^cApplied Scoences, University of Tsukuba, Tsukuba, Ibaraki 305-8571, Japan
^*Correspondence e-mail: isozaki.katsuhiro@nims.go.jp

(Received 10 October 2009; accepted 15 October 2009; online 23 October 2009)

The title compound, [Pt(C₁₅H₁₈NO₂S)Cl], was obtained by the cyclometallation reaction of cis-bis(benzonitrile)dichloridoplatinum(II) with N-benzylidene-L-methionine allyl ester in refluxing toluene. The Pt^II atom has a square-planar geometry and is tetra-coordinated by the Cl atom and the C, N and S atoms from the benzylidene methionine ester ligand. In the crystal structure, the S atoms show opposite chiral configurations with respect to the α-carbon of the methionine, reducing steric repulsion between the methyl and allyl ester groups.

Related literature

For cyclometallated Pt^II complexes having terdentate benzylidenamine ligands cyclometallated benzylideneamine, see: Capapé et al. (2005 ); Caubet et al. (2003 ); Riera et al. (2000 ). For organometallic amino acid complexes, see: Severin et al. (1998 ).

Experimental

Crystal data

[Pt(C₁₅H₁₈NO₂S)Cl]
M_r = 506.90
Monoclinic, P 2₁ /n
a = 8.6000 (13) Å
b = 9.5093 (14) Å
c = 19.679 (3) Å
β = 94.398 (2)°
V = 1604.6 (4) Å³
Z = 4
Mo Kα radiation
μ = 9.04 mm⁻¹
T = 180 K
0.50 × 0.10 × 0.10 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2003 ) T_min = 0.610, T_max = 0.862
12273 measured reflections
3105 independent reflections
2854 reflections with I > 2σ(I)
R_int = 0.024

Refinement

R[F² > 2σ(F²)] = 0.020
wR(F²) = 0.052
S = 1.07
3105 reflections
191 parameters
H-atom parameters constrained
Δρ_max = 1.36 e Å⁻³
Δρ_min = −0.48 e Å⁻³

Data collection: SMART (Bruker, 2003); cell refinement: SAINT (Bruker, 2003); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997 ); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Supporting information

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S160053680904238X/is2471sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S160053680904238X/is2471Isup2.hkl

checkCIF report

Comment top

Research on cyclometallated complexes (Capapé et al., 2005; Riera et al., 2000) has been focused because of their fundamental applications as luminescent materials (Caubet et al., 2003) and catalysts for a range of cross-coupling reactions. Amino acids, possessing natural chiral backbone and strong coordinating groups, are one of the potent candidates for designing stable cyclometallated complexes with highly controlled stereo-structure (Severin et al., 1998). Here, we report the crystal structure of the platinum (II) complex (1), containing chiral methionine-derived C,N,S-terdentate ligand.

The crystal structure of title compound (1) is presented in Fig. 1. The Pt(II) atom is tetracoordinated in a square-planar environment by a Cl atom and C, N, S atoms from benzylidene methionine ester ligand. In the [Pt (C₁₅H₁₈NO₂S)Cl] (1), S atoms showed opposite chiral configurations to the α-carbon of methionine for reducing steric repulsion between methyl and allyl ester groups (Fig. 2).

Related literature top

For cyclometallated benzylideneamine terdentate Pt^II complexes, see: Capapé et al. (2005); Caubet et al. (2003); Riera et al. (2000). For organometallic amino acid complexes, see: Severin et al. (1998).

Experimental top

The methionine-derived ligand was synthesized from three step reactions, esterification, deprotection, condensation using Fmoc-L-methionine as a starting material (Fig. 3). A suspension of cis-[PtCl₂(PhCN)₂] and methionine-derived ligand was refluxed under nitrogen atmosphere for 3 h. The crude mixture was purified by SiO₂ flash column chromatography. Single crystals for X-ray analyses were obtained from a CH₂Cl₂ solution.

Structure description top

Computing details top

Data collection: SMART (Bruker, 2003); cell refinement: SAINT (Bruker, 2003); data reduction: SAINT (Bruker, 2003); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. ORTEP drawing of (R_C,S_S)-1 with 50% probability displacement.
	Fig. 2. The packing structure of (1). Hydrogen atoms are omitted for clarity.
	Fig. 3. Synthetic scheme of the amino acid-derived ligand for 1.

(RS_C,SR_S)-(2-{[1-allyloxycarbonyl-3- (methylsulfanyl)propyl]iminomethyl}phenyl- κ³S,N,C¹)chloridoplatinum(II) top

Crystal data top

[Pt(C₁₅H₁₈NO₂S)Cl]	F(000) = 968
M_r = 506.90	D_x = 2.098 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 1024 reflections
a = 8.6000 (13) Å	θ = 2.8–26.0°
b = 9.5093 (14) Å	µ = 9.04 mm⁻¹
c = 19.679 (3) Å	T = 180 K
β = 94.398 (2)°	Prism, orange
V = 1604.6 (4) Å³	0.50 × 0.10 × 0.10 mm
Z = 4

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	3105 independent reflections
Radiation source: fine-focus sealed tube	2854 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.024
ω scans	θ_max = 26.0°, θ_min = 2.4°
Absorption correction: multi-scan (SADABS; Bruker, 2003)	h = −9→10
T_min = 0.610, T_max = 0.862	k = −11→11
12273 measured reflections	l = −24→24

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.020	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.052	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.033P)² + 0.6405P] where P = (F_o² + 2F_c²)/3
3105 reflections	(Δ/σ)_max = 0.003
191 parameters	Δρ_max = 1.36 e Å⁻³
0 restraints	Δρ_min = −0.48 e Å⁻³

Crystal data top

[Pt(C₁₅H₁₈NO₂S)Cl]	V = 1604.6 (4) Å³
M_r = 506.90	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 8.6000 (13) Å	µ = 9.04 mm⁻¹
b = 9.5093 (14) Å	T = 180 K
c = 19.679 (3) Å	0.50 × 0.10 × 0.10 mm
β = 94.398 (2)°

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	3105 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2003)	2854 reflections with I > 2σ(I)
T_min = 0.610, T_max = 0.862	R_int = 0.024
12273 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.020	0 restraints
wR(F²) = 0.052	H-atom parameters constrained
S = 1.07	Δρ_max = 1.36 e Å⁻³
3105 reflections	Δρ_min = −0.48 e Å⁻³
191 parameters

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.

Refinement. Refinement of F² against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F², conventional R-factors R are based on F, with F set to zero for negative F². The threshold expression of F² > σ(F²) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F² are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Pt1	0.456604 (14)	0.848674 (12)	0.309063 (6)	0.01942 (6)
S4	0.63428 (10)	0.87893 (9)	0.22448 (5)	0.02394 (18)
Cl1	0.60649 (11)	1.00955 (10)	0.37235 (5)	0.0338 (2)
C3	0.3033 (4)	0.8222 (3)	0.37990 (18)	0.0224 (7)
N4	0.3141 (3)	0.7078 (3)	0.26035 (14)	0.0222 (6)
C6	0.1849 (5)	0.9473 (5)	−0.0659 (2)	0.0518 (12)
H6A	0.1530	0.8793	−0.0980	0.062*
H6B	0.2203	1.0341	−0.0801	0.062*
O7	0.1383 (4)	0.8499 (3)	0.16257 (16)	0.0423 (7)
C9	0.2011 (4)	0.6636 (3)	0.29340 (19)	0.0258 (8)
H9	0.1318	0.5959	0.2752	0.031*
C11	0.1695 (5)	0.8600 (4)	0.4821 (2)	0.0331 (9)
H11	0.1639	0.9067	0.5234	0.040*
O12	0.2371 (3)	0.7266 (3)	0.07819 (13)	0.0377 (6)
C13	0.1798 (5)	0.9200 (5)	0.0011 (3)	0.0497 (11)
H13	0.2122	0.9893	0.0324	0.060*
C15	0.1855 (4)	0.7230 (3)	0.36017 (17)	0.0242 (7)
C16	0.5768 (4)	0.7677 (4)	0.15222 (17)	0.0277 (7)
H16A	0.5139	0.8229	0.1190	0.033*
H16B	0.6699	0.7388	0.1311	0.033*
C17	0.2223 (4)	0.7597 (4)	0.14303 (18)	0.0292 (8)
C18	0.0640 (4)	0.6922 (4)	0.40057 (19)	0.0322 (8)
H18	−0.0100	0.6246	0.3868	0.039*
C19	0.2922 (4)	0.8882 (4)	0.44249 (18)	0.0274 (7)
H19	0.3685	0.9524	0.4580	0.033*
C20	0.0548 (4)	0.7633 (4)	0.46131 (18)	0.0366 (9)
H20	−0.0277	0.7465	0.4881	0.044*
C21	0.1259 (5)	0.7871 (5)	0.0261 (2)	0.0469 (11)
H21A	0.1100	0.7217	−0.0116	0.056*
H21B	0.0264	0.8009	0.0453	0.056*
C27	0.8092 (4)	0.7906 (4)	0.2577 (2)	0.0355 (9)
H27A	0.7881	0.6922	0.2627	0.053*
H27B	0.8434	0.8298	0.3012	0.053*
H27C	0.8892	0.8029	0.2268	0.053*
C28	0.3198 (4)	0.6605 (3)	0.18980 (18)	0.0246 (8)
H28	0.2675	0.5689	0.1867	0.030*
C29	0.4852 (4)	0.6366 (3)	0.16894 (19)	0.0270 (8)
H29A	0.5436	0.5870	0.2056	0.032*
H29B	0.4793	0.5756	0.1293	0.032*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Pt1	0.01859 (9)	0.02131 (9)	0.01877 (9)	−0.00125 (4)	0.00404 (6)	−0.00029 (4)
S4	0.0227 (4)	0.0254 (4)	0.0247 (5)	0.0004 (3)	0.0077 (3)	0.0000 (3)
Cl1	0.0320 (5)	0.0411 (5)	0.0291 (5)	−0.0148 (4)	0.0066 (4)	−0.0086 (4)
C3	0.0202 (18)	0.0253 (16)	0.0217 (18)	−0.0021 (13)	0.0012 (14)	0.0065 (13)
N4	0.0247 (15)	0.0216 (14)	0.0206 (14)	−0.0022 (11)	0.0042 (11)	−0.0008 (11)
C6	0.046 (3)	0.062 (3)	0.050 (3)	0.009 (2)	0.020 (2)	0.018 (2)
O7	0.0392 (17)	0.0494 (18)	0.0387 (17)	0.0171 (13)	0.0061 (14)	0.0016 (12)
C9	0.0243 (19)	0.0242 (18)	0.029 (2)	−0.0058 (13)	0.0012 (15)	−0.0004 (13)
C11	0.030 (2)	0.047 (2)	0.022 (2)	−0.0010 (16)	0.0050 (16)	−0.0026 (15)
O12	0.0289 (14)	0.0599 (18)	0.0244 (13)	0.0047 (13)	0.0030 (11)	0.0035 (12)
C13	0.036 (2)	0.052 (3)	0.062 (3)	0.007 (2)	0.005 (2)	0.001 (2)
C15	0.0224 (17)	0.0290 (18)	0.0211 (17)	−0.0015 (13)	0.0013 (13)	0.0021 (13)
C16	0.0244 (18)	0.036 (2)	0.0236 (17)	0.0017 (15)	0.0079 (14)	−0.0030 (15)
C17	0.0224 (18)	0.037 (2)	0.0287 (19)	−0.0002 (15)	0.0044 (14)	0.0039 (16)
C18	0.024 (2)	0.042 (2)	0.030 (2)	−0.0109 (16)	0.0030 (15)	0.0034 (17)
C19	0.0253 (19)	0.0330 (18)	0.0240 (18)	−0.0018 (15)	0.0021 (14)	−0.0021 (15)
C20	0.028 (2)	0.059 (3)	0.0234 (19)	−0.0062 (18)	0.0097 (15)	0.0058 (17)
C21	0.036 (2)	0.071 (3)	0.033 (2)	0.000 (2)	−0.0041 (18)	0.009 (2)
C27	0.0222 (19)	0.043 (2)	0.041 (2)	0.0063 (16)	0.0015 (16)	−0.0047 (18)
C28	0.029 (2)	0.0233 (18)	0.0219 (18)	−0.0019 (13)	0.0018 (15)	−0.0044 (12)
C29	0.027 (2)	0.0287 (18)	0.0255 (19)	0.0064 (14)	0.0037 (15)	−0.0075 (14)

Geometric parameters (Å, º) top

Pt1—C3	2.006 (4)	C13—C21	1.446 (7)
Pt1—N4	2.009 (3)	C13—H13	0.9300
Pt1—Cl1	2.3037 (9)	C15—C18	1.392 (5)
Pt1—S4	2.3618 (9)	C16—C29	1.524 (5)
S4—C27	1.801 (4)	C16—H16A	0.9700
S4—C16	1.810 (3)	C16—H16B	0.9700
C3—C19	1.392 (5)	C17—C28	1.524 (5)
C3—C15	1.417 (5)	C18—C20	1.381 (5)
N4—C9	1.281 (4)	C18—H18	0.9300
N4—C28	1.464 (4)	C19—H19	0.9300
C6—C13	1.348 (6)	C20—H20	0.9300
C6—H6A	0.9300	C21—H21A	0.9700
C6—H6B	0.9300	C21—H21B	0.9700
O7—C17	1.204 (4)	C27—H27A	0.9600
C9—C15	1.446 (5)	C27—H27B	0.9600
C9—H9	0.9300	C27—H27C	0.9600
C11—C19	1.386 (5)	C28—C29	1.528 (5)
C11—C20	1.387 (5)	C28—H28	0.9800
C11—H11	0.9300	C29—H29A	0.9700
O12—C17	1.330 (4)	C29—H29B	0.9700
O12—C21	1.464 (5)

C3—Pt1—N4	80.72 (13)	O7—C17—O12	125.4 (3)
C3—Pt1—Cl1	94.46 (10)	O7—C17—C28	124.4 (3)
N4—Pt1—Cl1	175.18 (8)	O12—C17—C28	110.1 (3)
C3—Pt1—S4	179.20 (10)	C20—C18—C15	119.1 (3)
N4—Pt1—S4	98.56 (8)	C20—C18—H18	120.4
Cl1—Pt1—S4	86.26 (3)	C15—C18—H18	120.4
C27—S4—C16	100.53 (18)	C11—C19—C3	121.2 (3)
C27—S4—Pt1	104.77 (14)	C11—C19—H19	119.4
C16—S4—Pt1	109.27 (12)	C3—C19—H19	119.4
C19—C3—C15	116.5 (3)	C18—C20—C11	119.6 (3)
C19—C3—Pt1	130.7 (3)	C18—C20—H20	120.2
C15—C3—Pt1	112.8 (2)	C11—C20—H20	120.2
C9—N4—C28	117.6 (3)	C13—C21—O12	111.9 (4)
C9—N4—Pt1	115.8 (2)	C13—C21—H21A	109.2
C28—N4—Pt1	126.4 (2)	O12—C21—H21A	109.2
C13—C6—H6A	120.0	C13—C21—H21B	109.2
C13—C6—H6B	120.0	O12—C21—H21B	109.2
H6A—C6—H6B	120.0	H21A—C21—H21B	107.9
N4—C9—C15	117.4 (3)	S4—C27—H27A	109.5
N4—C9—H9	121.3	S4—C27—H27B	109.5
C15—C9—H9	121.3	H27A—C27—H27B	109.5
C19—C11—C20	121.1 (4)	S4—C27—H27C	109.5
C19—C11—H11	119.4	H27A—C27—H27C	109.5
C20—C11—H11	119.4	H27B—C27—H27C	109.5
C17—O12—C21	118.2 (3)	N4—C28—C17	109.0 (3)
C6—C13—C21	122.5 (5)	N4—C28—C29	113.6 (3)
C6—C13—H13	118.8	C17—C28—C29	114.2 (3)
C21—C13—H13	118.8	N4—C28—H28	106.5
C18—C15—C3	122.4 (3)	C17—C28—H28	106.5
C18—C15—C9	124.2 (3)	C29—C28—H28	106.5
C3—C15—C9	113.3 (3)	C16—C29—C28	116.4 (3)
C29—C16—S4	115.0 (2)	C16—C29—H29A	108.2
C29—C16—H16A	108.5	C28—C29—H29A	108.2
S4—C16—H16A	108.5	C16—C29—H29B	108.2
C29—C16—H16B	108.5	C28—C29—H29B	108.2
S4—C16—H16B	108.5	H29A—C29—H29B	107.4
H16A—C16—H16B	107.5

N4—Pt1—S4—C27	−107.41 (16)	C21—O12—C17—C28	165.9 (3)
Cl1—Pt1—S4—C27	72.70 (14)	C3—C15—C18—C20	1.8 (6)
Cl1—Pt1—S4—C16	179.70 (13)	C9—C15—C18—C20	−175.2 (3)
N4—Pt1—C3—C19	−176.3 (4)	C20—C11—C19—C3	1.1 (6)
Cl1—Pt1—C3—C19	3.6 (3)	C15—C3—C19—C11	−1.6 (5)
N4—Pt1—C3—C15	1.1 (2)	Pt1—C3—C19—C11	175.8 (3)
Cl1—Pt1—C3—C15	−179.0 (2)	C15—C18—C20—C11	−2.4 (6)
C3—Pt1—N4—C9	−1.8 (3)	C19—C11—C20—C18	1.0 (6)
S4—Pt1—N4—C9	178.5 (2)	C6—C13—C21—O12	128.9 (4)
C3—Pt1—N4—C28	172.9 (3)	C17—O12—C21—C13	90.1 (5)
S4—Pt1—N4—C28	−6.8 (3)	C9—N4—C28—C17	86.9 (4)
C28—N4—C9—C15	−173.0 (3)	Pt1—N4—C28—C17	−87.7 (3)
Pt1—N4—C9—C15	2.2 (4)	C9—N4—C28—C29	−144.4 (3)
C19—C3—C15—C18	0.1 (5)	Pt1—N4—C28—C29	40.9 (4)
Pt1—C3—C15—C18	−177.7 (3)	O7—C17—C28—N4	−9.1 (5)
C19—C3—C15—C9	177.5 (3)	O12—C17—C28—N4	174.3 (3)
Pt1—C3—C15—C9	−0.3 (4)	O7—C17—C28—C29	−137.4 (4)
N4—C9—C15—C18	176.1 (3)	O12—C17—C28—C29	46.0 (4)
N4—C9—C15—C3	−1.2 (4)	S4—C16—C29—C28	69.7 (4)
C27—S4—C16—C29	83.2 (3)	N4—C28—C29—C16	−78.1 (4)
Pt1—S4—C16—C29	−26.7 (3)	C17—C28—C29—C16	47.8 (4)
C21—O12—C17—O7	−10.6 (6)

Experimental details

Crystal data
Chemical formula	[Pt(C₁₅H₁₈NO₂S)Cl]
M_r	506.90
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	180
a, b, c (Å)	8.6000 (13), 9.5093 (14), 19.679 (3)
β (°)	94.398 (2)
V (Å³)	1604.6 (4)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	9.04
Crystal size (mm)	0.50 × 0.10 × 0.10

Data collection
Diffractometer	Bruker SMART APEX CCD area-detector
Absorption correction	Multi-scan (SADABS; Bruker, 2003)
T_min, T_max	0.610, 0.862
No. of measured, independent and observed [I > 2σ(I)] reflections	12273, 3105, 2854
R_int	0.024
(sin θ/λ)_max (Å⁻¹)	0.617

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.020, 0.052, 1.07
No. of reflections	3105
No. of parameters	191
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	1.36, −0.48

Computer programs: SMART (Bruker, 2003), SAINT (Bruker, 2003), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997), SHELXTL (Sheldrick, 2008).

Acknowledgements

This work was supported financially by the Ministry of Education, Science, Sports and Culture, Grant-in-Aid for Young Scientists (Start-up, 19850030).

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