μ-Glycine-κ²O:O′-di-μ-sulfido-bis­[(gly­cin­ato-κ²N,O)oxidomolybdenum(V)]

In the title compound, [Mo₂(C₂H₄NO₂)₂O₂S₂(C₂H₅NO₂)], the two Mo^V atoms are bridged by two μ₂-S atoms and one glycine ligand in an O:O′-bidentate mode. In addition, each Mo^V atom is bonded to one terminal oxygen ligand and chelated by one N,O-bidentate glycinate ligand, resulting in a distorted octa­hedral coordination. A complex hydrogen-bonding network is constructed by inter­molecular N—H...O hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 295 K
• Mean [sigma](C-C) = 0.023 Å
• R factor = 0.087
• wR factor = 0.178
• Data-to-parameter ratio = 13.3

checkCIF/PLATON results

No syntax errors found



Alert level B
ABSTM02_ALERT_3_B  The ratio of expected to reported Tmax/Tmin(RR') is < 0.75
            Tmin and Tmax reported:      0.483     0.813
            Tmin(prime) and Tmax expected:      0.655     0.813
            RR(prime) =      0.737
            Please check that your absorption correction is appropriate.
PLAT027_ALERT_3_B _diffrn_reflns_theta_full (too) Low ............      24.99 Deg.
PLAT061_ALERT_3_B Tmax/Tmin Range Test RR' too Large .............       0.72
PLAT342_ALERT_3_B Low Bond Precision on C-C Bonds (x 1000) Ang ...         23

Alert level C
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Mo1    -   S1      ..       6.95 su
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Mo2    -   S1      ..       8.46 su
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for         S1
PLAT420_ALERT_2_C D-H Without Acceptor       N2     -   H2B    ...          ?

Alert level G
PLAT794_ALERT_5_G Check Predicted Bond Valency for Mo1         (5)       5.10
PLAT794_ALERT_5_G Check Predicted Bond Valency for Mo2         (5)       5.26

   0 ALERT level A = In general: serious problem
   4 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   2 ALERT level G = General alerts; check

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   4 ALERT type 2 Indicator that the structure model may be wrong or deficient
   4 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   2 ALERT type 5 Informative message, check

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S1. Comment

Dimolybdenum complexes containing [Mo₂O₂(µ-S)₂] have attracted many chemists' attention, not only because the [Mo₂O₂(µ-S)₂] unit has special stability but also because it may be employed as a starting material to react with many transition metals. Some [Mo₂O₂(µ-S)₂] structural compounds based on amino-acid have been isolated and structurally characterized (Spivack & Dori, 1975; Li et al., 2005). The crystal structure of our new neutral dimolybdenum glycinato complex is similar to the compound [Mo₂O₄(C₂H₄NO₂)₂(C₂H₅NO₂)] (Liu et al., 2000).

The title structure consists of the neutral Mo₂O₂(µ-S)₂(C₂H₅NO₂)(C₂H₄NO₂)₂ (Fig. 1). In the structure, the two molybdenum atoms are not crystallographically equivalent, which are linked by two µ₂-S ligand and one glycine (⁺H₃NCH₂COO^-) ligand in an O:O'-bidentate mode. Each Mo^V atom is also bonded to one terminal oxygen atom and chelated by one N,O-glycine (NH₂CH₂COO^-) ligand, resulting in a distorted octahedral coordination. The Mo···Mo separation is 2.788 (2) Å, which is shorter than the Mo···Mo distance (2.848 (1) Å) in the histidinato complex (Spivack & Dori, 1975). The Mo—S, Mo—N, Mo—O and Mo?O bond lengths are 2.304 (5)—2.336 (4) Å, 2.195 (12)—2.225 (11) Å, 2.091 (11)—2.328 (9) Å and 1.668 (11)—1.696 (10) Å, respectively.

A three-dimensional network is constructed by six classic intermolecular N—H···O hydrogen bonds (Table 1 and Fig. 2).

Related literature

For related structure, see: Spivack & Dori (1975); Li et al. (2005); Liu et al. (2000); Lin et al. (1998).

S2. Experimental

The title compound was prepared by adding a solution of glycin (0.075 g, 1 mmol) in 5 ml H₂O to a solution of (Et₄N)₂Mo₂S₂O₂(edt)₂ (0.366 g, 0.5 mmol) in 5 ml DMF. After stirring about 10 min, the solution was filtered. Orange block crystals of the title compound were obtained by slow evaporation of the orange filtrate for several weeks. (Et₄N)₂Mo₂S₂O₂(edt)₂ was synthesized by the literature (Lin et al.,1998).

S3. Refinement

All H atoms were positioned geometrically and treated as riding atoms (including free rotation about the C—NH₃⁺ bond), with C—H = 0.97 Å and N—H = 0.89—0.90 Å, with U_iso(H) = 1.2 U_eq(C, N) (1.5 for —NH₃⁺ groups). R_int value of 0.086 and R of 0.0869 indicate a low structure quality.

Computing details

Data collection: SMART (Siemens, 1996); cell refinement: SAINT (Siemens, 1996); data reduction: SAINT (Siemens, 1996); program(s) used to solve structure: SHELXTL (Siemens, 1996); program(s) used to refine structure: SHELXTL (Siemens, 1996); molecular graphics: SHELXTL (Siemens, 1996); software used to prepare material for publication: SHELXTL (Siemens, 1996).

Figures

	Fig. 1. The molecular structure of the title compound, with atom labels and 30% probability displacement ellipsoids for non-H atoms.
	Fig. 2. A view of the crystal packing along the b axis. Hydrogen bonds are shown as dashed lines.

µ-Glycine-κ²O:O'-di-µ-sulfido- bis[(glycinato-κ²N,O)oxidomolybdenum(V)]

Crystal data

[Mo2(C2H4NO2)2O2S2(C2H5NO2)]	F(000) = 1000
Mr = 511.19	Dx = 2.353 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 45 reflections
a = 13.1258 (13) Å	θ = 2.5–25.0°
b = 10.8384 (10) Å	µ = 2.07 mm^−1
c = 10.585 (1) Å	T = 295 K
β = 106.597 (2)°	Block, orange
V = 1443.1 (2) Å^3	0.20 × 0.15 × 0.10 mm
Z = 4

Data collection

Bruker SMART CCD area-detector diffractometer	2519 independent reflections
Radiation source: fine-focus sealed tube	1620 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.086
phi and ω scans	θmax = 25.0°, θmin = 2.5°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −15→13
Tmin = 0.483, Tmax = 0.813	k = −12→7
4358 measured reflections	l = −7→12

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.087	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.178	H-atom parameters constrained
S = 1.11	w = 1/[σ^2(Fo^2) + (0.0001P)^2 + 52.2323P] where P = (Fo^2 + 2Fc^2)/3
2519 reflections	(Δ/σ)max < 0.001
190 parameters	Δρmax = 1.16 e Å^−3
0 restraints	Δρmin = −1.10 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Mo1	0.72243 (11)	0.35843 (13)	0.32342 (13)	0.0272 (4)
Mo2	0.64096 (11)	0.59751 (13)	0.30419 (13)	0.0281 (4)
S1	0.7788 (4)	0.5267 (4)	0.2284 (5)	0.0513 (13)
S2	0.5926 (3)	0.4310 (4)	0.4150 (4)	0.0355 (10)
O1	1.0118 (9)	0.1842 (12)	0.4619 (12)	0.051 (3)
O2	0.8716 (8)	0.2768 (10)	0.3310 (10)	0.034 (3)
O3	0.6503 (8)	0.2828 (10)	0.1868 (10)	0.036 (3)
O4	0.5367 (8)	0.6025 (11)	0.1700 (10)	0.040 (3)
O5	0.7134 (10)	0.9688 (11)	0.3142 (13)	0.051 (3)
O6	0.7004 (8)	0.7698 (10)	0.2716 (10)	0.033 (3)
O7	0.7740 (7)	0.6195 (10)	0.5025 (10)	0.030 (3)
O8	0.8358 (9)	0.4270 (10)	0.5171 (10)	0.035 (3)
N1	0.7391 (10)	0.1977 (10)	0.4585 (12)	0.027 (3)
H1A	0.7119	0.2171	0.5250	0.032*
H1B	0.7018	0.1336	0.4143	0.032*
N2	0.5774 (10)	0.7223 (11)	0.4264 (12)	0.030 (3)
H2A	0.5061	0.7154	0.4028	0.036*
H2B	0.6023	0.6992	0.5113	0.036*
N3	0.9018 (10)	0.6917 (13)	0.7315 (12)	0.035 (3)
H3A	0.9475	0.7059	0.8101	0.053*
H3B	0.8358	0.7047	0.7355	0.053*
H3E	0.9156	0.7423	0.6722	0.053*
C1	0.9187 (14)	0.2111 (16)	0.4302 (18)	0.040 (4)
C2	0.8498 (12)	0.1619 (18)	0.5123 (16)	0.043 (5)
H2C	0.8547	0.0726	0.5158	0.052*
H2D	0.8763	0.1929	0.6016	0.052*
C3	0.6054 (14)	0.8498 (15)	0.4143 (17)	0.040 (4)
H3C	0.6394	0.8823	0.5016	0.047*
H3D	0.5409	0.8968	0.3775	0.047*
C4	0.6778 (13)	0.8681 (16)	0.3302 (14)	0.034 (4)
C5	0.9124 (13)	0.5617 (16)	0.6923 (17)	0.042 (4)
H5A	0.9843	0.5468	0.6884	0.050*
H5B	0.8980	0.5061	0.7569	0.050*
C6	0.8361 (12)	0.5390 (16)	0.5617 (14)	0.029 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Mo1	0.0314 (8)	0.0282 (8)	0.0244 (7)	−0.0040 (6)	0.0116 (6)	−0.0006 (6)
Mo2	0.0289 (8)	0.0300 (8)	0.0281 (7)	0.0000 (6)	0.0128 (6)	0.0005 (6)
S1	0.062 (3)	0.035 (3)	0.061 (3)	0.000 (2)	0.024 (3)	−0.004 (2)
S2	0.039 (3)	0.035 (3)	0.038 (2)	−0.0018 (19)	0.019 (2)	0.0015 (19)
O1	0.032 (7)	0.057 (9)	0.062 (9)	0.005 (6)	0.010 (6)	0.015 (7)
O2	0.026 (6)	0.046 (7)	0.035 (6)	0.002 (5)	0.017 (5)	0.003 (6)
O3	0.037 (7)	0.039 (7)	0.032 (6)	−0.012 (5)	0.012 (5)	−0.001 (5)
O4	0.035 (7)	0.052 (8)	0.037 (6)	0.004 (6)	0.016 (5)	0.007 (6)
O5	0.058 (9)	0.030 (7)	0.078 (10)	−0.009 (6)	0.038 (8)	−0.005 (7)
O6	0.038 (7)	0.025 (6)	0.043 (7)	0.005 (5)	0.023 (6)	0.006 (5)
O7	0.015 (5)	0.038 (7)	0.030 (6)	−0.004 (5)	−0.004 (4)	−0.006 (5)
O8	0.046 (7)	0.033 (7)	0.028 (6)	−0.004 (5)	0.012 (5)	0.002 (5)
N1	0.044 (8)	0.007 (6)	0.037 (7)	−0.003 (6)	0.023 (6)	−0.002 (5)
N2	0.032 (8)	0.031 (8)	0.030 (7)	0.001 (6)	0.012 (6)	0.001 (6)
N3	0.031 (8)	0.053 (10)	0.024 (7)	−0.003 (7)	0.011 (6)	−0.007 (6)
C1	0.033 (11)	0.037 (11)	0.053 (12)	0.010 (8)	0.015 (9)	0.002 (9)
C2	0.028 (10)	0.067 (14)	0.033 (10)	−0.012 (9)	0.004 (8)	0.000 (9)
C3	0.047 (11)	0.030 (10)	0.050 (11)	0.000 (8)	0.028 (9)	−0.005 (8)
C4	0.035 (9)	0.040 (11)	0.021 (8)	−0.003 (8)	−0.003 (7)	0.003 (8)
C5	0.034 (10)	0.045 (11)	0.047 (11)	0.007 (8)	0.012 (8)	−0.011 (9)
C6	0.017 (8)	0.049 (11)	0.021 (8)	0.012 (8)	0.003 (7)	0.004 (8)

Geometric parameters (Å, º)

Mo1—O3	1.696 (10)	N1—C2	1.454 (19)
Mo1—O2	2.129 (10)	N1—H1A	0.9000
Mo1—N1	2.225 (11)	N1—H1B	0.9000
Mo1—O8	2.286 (11)	N2—C3	1.44 (2)
Mo1—S1	2.304 (5)	N2—H2A	0.9000
Mo1—S2	2.325 (4)	N2—H2B	0.9000
Mo1—Mo2	2.788 (2)	N3—C5	1.49 (2)
Mo2—O4	1.668 (11)	N3—H3A	0.8900
Mo2—O6	2.091 (11)	N3—H3B	0.8900
Mo2—N2	2.195 (12)	N3—H3E	0.8900
Mo2—S1	2.310 (5)	C1—C2	1.52 (2)
Mo2—O7	2.328 (9)	C2—H2C	0.9700
Mo2—S2	2.336 (4)	C2—H2D	0.9700
O1—C1	1.206 (19)	C3—C4	1.49 (2)
O2—C1	1.274 (19)	C3—H3C	0.9700
O5—C4	1.219 (19)	C3—H3D	0.9700
O6—C4	1.308 (19)	C5—C6	1.48 (2)
O7—C6	1.235 (17)	C5—H5A	0.9700
O8—C6	1.303 (19)	C5—H5B	0.9700
O3—Mo1—O2	96.6 (5)	C6—O8—Mo1	124.2 (9)
O3—Mo1—N1	95.6 (5)	C2—N1—Mo1	111.4 (9)
O2—Mo1—N1	74.3 (4)	C2—N1—H1A	109.3
O3—Mo1—O8	169.5 (5)	Mo1—N1—H1A	109.3
O2—Mo1—O8	75.2 (4)	C2—N1—H1B	109.3
N1—Mo1—O8	76.0 (4)	Mo1—N1—H1B	109.3
O3—Mo1—S1	100.4 (4)	H1A—N1—H1B	108.0
O2—Mo1—S1	86.5 (3)	C3—N2—Mo2	112.8 (9)
N1—Mo1—S1	156.3 (4)	C3—N2—H2A	109.0
O8—Mo1—S1	85.8 (3)	Mo2—N2—H2A	109.0
O3—Mo1—S2	102.8 (4)	C3—N2—H2B	109.0
O2—Mo1—S2	154.2 (3)	Mo2—N2—H2B	109.0
N1—Mo1—S2	86.9 (3)	H2A—N2—H2B	107.8
O8—Mo1—S2	83.3 (3)	C5—N3—H3A	109.5
S1—Mo1—S2	106.19 (17)	C5—N3—H3B	109.5
O3—Mo1—Mo2	106.1 (4)	H3A—N3—H3B	109.5
O2—Mo1—Mo2	135.9 (3)	C5—N3—H3E	109.5
N1—Mo1—Mo2	137.7 (3)	H3A—N3—H3E	109.5
O8—Mo1—Mo2	84.3 (3)	H3B—N3—H3E	109.5
S1—Mo1—Mo2	52.90 (13)	O1—C1—O2	125.3 (16)
S2—Mo1—Mo2	53.45 (11)	O1—C1—C2	118.6 (16)
O4—Mo2—O6	94.9 (5)	O2—C1—C2	116.1 (14)
O4—Mo2—N2	97.1 (5)	N1—C2—C1	112.0 (14)
O6—Mo2—N2	76.7 (4)	N1—C2—H2C	109.2
O4—Mo2—S1	104.4 (4)	C1—C2—H2C	109.2
O6—Mo2—S1	82.7 (3)	N1—C2—H2D	109.2
N2—Mo2—S1	151.3 (4)	C1—C2—H2D	109.2
O4—Mo2—O7	170.5 (5)	H2C—C2—H2D	107.9
O6—Mo2—O7	80.7 (4)	N2—C3—C4	113.7 (13)
N2—Mo2—O7	73.7 (4)	N2—C3—H3C	108.8
S1—Mo2—O7	83.5 (3)	C4—C3—H3C	108.8
O4—Mo2—S2	100.2 (4)	N2—C3—H3D	108.8
O6—Mo2—S2	160.1 (3)	C4—C3—H3D	108.8
N2—Mo2—S2	88.7 (3)	H3C—C3—H3D	107.7
S1—Mo2—S2	105.66 (17)	O5—C4—O6	121.1 (15)
O7—Mo2—S2	82.4 (3)	O5—C4—C3	122.5 (16)
O4—Mo2—Mo1	107.2 (4)	O6—C4—C3	116.4 (14)
O6—Mo2—Mo1	133.5 (3)	C6—C5—N3	109.0 (14)
N2—Mo2—Mo1	137.1 (3)	C6—C5—H5A	109.9
S1—Mo2—Mo1	52.73 (13)	N3—C5—H5A	109.9
O7—Mo2—Mo1	81.7 (3)	C6—C5—H5B	109.9
S2—Mo2—Mo1	53.08 (11)	N3—C5—H5B	109.9
Mo1—S1—Mo2	74.36 (16)	H5A—C5—H5B	108.3
Mo1—S2—Mo2	73.47 (13)	O7—C6—O8	122.7 (14)
C1—O2—Mo1	119.2 (10)	O7—C6—C5	122.0 (15)
C4—O6—Mo2	120.2 (10)	O8—C6—C5	115.2 (14)
C6—O7—Mo2	127.0 (10)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1A···O3^i	0.90	2.09	2.975 (16)	167
N1—H1B···O5^ii	0.90	2.10	2.882 (16)	144
N2—H2A···O3^iii	0.90	2.13	2.958 (16)	153
N3—H3A···O1^iv	0.89	2.33	3.119 (17)	148
N3—H3B···O6^v	0.89	1.94	2.825 (16)	172
N3—H3E···O1^vi	0.89	2.08	2.934 (17)	160

Symmetry codes: (i) x, −y+1/2, z+1/2; (ii) x, y−1, z; (iii) −x+1, y+1/2, −z+1/2; (iv) −x+2, y+1/2, −z+3/2; (v) x, −y+3/2, z+1/2; (vi) −x+2, −y+1, −z+1.