[Oxybis(ethane-1,2-di­yl)]bis­(di­methyl­ammonium) octa­molybdate dihydrate

Ermert, D.M.; Gembicky, M.; Rheingold, A.L.

doi:10.1107/S2414314619015360

metal-organic compounds

IUCrDATA

ISSN: 2414-3146

Volume 4| Part 11| November 2019| x191536

https://doi.org/10.1107/S2414314619015360

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[Oxybis(ethane-1,2-diyl)]bis(dimethylammonium) octamolybdate dihydrate

David M. Ermert,^a ^* Milan Gembicky ^b and Arnold L. Rheingold ^b

^aEntegris, Inc., 7 Commerce Dr., Danbury, CT, 06810, USA, and ^bDepartment of Chemistry, University of California, 9500 Gilman Drive, La Jolla, CA, 92093, USA
^*Correspondence e-mail: David.Ermert@entegris.com

Edited by A. J. Lough, University of Toronto, Canada (Received 1 August 2019; accepted 13 November 2019; online 19 November 2019)

The title compound, (C₈H₂₂N₂O)₂[Mo₈O₂₆]·H₂O, (cis-H₂L)₂[β-Mo₈O₂₆]·H₂O, where L = (bis[2-N,N-dimethylamino)ethyl] ether), was synthesized from bis[2-(dimethylamino)ethyl] ether and MoO₃ under solvothermal conditions and characterized by multinuclear NMR and single-crystal X-ray diffraction techniques. The structure displays two [oxybis(ethane-1,2-diyl)]bis(dimethylammonium), or [cis-H₂L]²⁺, cations, a central [β-Mo₈O₂₆]⁴⁻ anionic cluster consisting of eight distorted MoO₆ octahedra, and two water molecules in their deuterated form. The central anion lies across an inversion center. The [cis-H₂L]²⁺ cations are hydrogen bonded to the central [β-Mo₈O₂₆]⁴⁻ cluster via bridging water molecules. In the crystal, O—H⋯O hydrogen bonds link the components into chains along [010]. Weak C—H⋯O hydrogen bonds link these chains into a three-dimensional network.

Keywords: crystal structure; molybdenum; molybdenum oxide; octamolybdate; polyoxomolybdate.

CCDC reference: 1965627

Structure description

Polyoxometalates (POMs) are self-assembled metal clusters finding broad application in coatings, the pulp and paper industry, catalysis, microelectronics, and medicine (Katsoulis, 1998 ; Chaidogiannos et al., 2004 ; Long et al., 2007 ; Rhule et al., 1998 ). Generally, group 5 and 6 POMs are more common and can adopt a wide range of nuclearity (Pope, 1983 ; Pope & Müller, 1991 ). Within the context of molybdenum, seven isomers of the octamolybdate anion, [Mo₈O₂₆]⁴⁻, have been reported (Bridgeman, 2002 ; Allis et al., 2004 ). Here, we report the isolation of the title compound (1), which is characterized by a protonated bis(dialkyl)ammonium ether salt linked to an octamolybdate anion through hydrogen bonding (Table 1).

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯O14	1.00	2.26	2.737 (6)	108
N1—H1⋯O15	1.00	1.97	2.916 (7)	157
N2—H2⋯O14	1.00	2.46	2.808 (7)	100
N2—H2⋯O15	1.00	1.87	2.863 (6)	170
O15—D15A⋯O4	0.87	1.99	2.854 (5)	170
O15—D15B⋯O4ⁱⁱ	0.87	1.99	2.863 (6)	177
C1—H1A⋯O5ⁱⁱⁱ	0.98	2.56	3.440 (6)	149
C1—H1B⋯O9	0.98	2.36	3.189 (7)	142
C1—H1C⋯O11ⁱⁱ	0.98	2.39	3.355 (8)	168
C2—H2A⋯O3^iv	0.98	2.44	3.343 (7)	153
C2—H2B⋯O10ⁱⁱ	0.98	2.34	3.300 (8)	167
C3—H3A⋯O13ⁱ	0.99	2.52	3.407 (7)	150
C3—H3B⋯O11ⁱⁱⁱ	0.99	2.42	3.266 (7)	143
C4—H4A⋯O6^v	0.99	2.50	3.472 (8)	167
C6—H6B⋯O6ⁱ	0.99	2.44	3.360 (8)	154
C7—H7A⋯O12^v	0.98	2.49	3.316 (8)	142
C7—H7B⋯O8ⁱⁱ	0.98	2.26	3.227 (8)	170
C8—H8A⋯O9^vi	0.98	2.48	3.402 (7)	157
C8—H8B⋯O9ⁱⁱ	0.98	2.48	3.461 (8)	176
C8—H8C⋯O11	0.98	2.40	3.155 (7)	134
C8—H8C⋯O7ⁱ	0.98	2.52	3.270 (8)	133
Symmetry codes: (i) -x+1, -y+1, -z+1; (ii) -x+1, -y, -z+1; (iii) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (iv) $[-x+{\script{1\over 2}}, y-{\script{1\over 2}}, -z+{\script{1\over 2}}]$ ; (v) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (vi) x+1, y, z.

Compound (1) (Fig. 1) crystallizes as a salt containing two [bis(2-N,N-dimethylammonium)ethyl ether]²⁺ cations and a [β-Mo₈O₂₆]⁴⁻ anion hydrogen bonded through a single water molecule (deuterated)of hydration per [H₂L]²⁺. The anion lies across a center of inversion. The protonated amino arms of the ether groups are arranged in a cis orientation and create a hydrogen-bonding pocket for D₂O coordination between both N—H protons of a given ether group and a μ₂-O-atom of the [Mo₈O₂₆]⁴⁻ anion. Overall, hydrogen-bond lengths range from 1.87–2.46 Å, with the close proximity of the ammonium protons to the oxygen atom of the ether group facilitating the longer (2.26–2.46 Å) hydrogen bonding. In the crystal, O—H⋯O hydrogen bonds link the components into chains (Fig. 2) along [010]. Furthermore, weak C—H⋯O hydrogen bonds link these chains into a three-dimensional network (Fig. 3). Although 1 was crystallized from D₂O, only the solvent molecules have been modeled with deuterium atoms; however, deuterium exchange with N—H protons is likely and supported by ¹H-NMR experiments (see below).

Figure 1
The molecular entities in the title compound with ellipsoids drawn at the 50% probability level. Only the symmetry-unique cation and solvent water molecules are shown. H atoms bonded to C atoms are omitted for the sake of clarity. Atoms labeled with the suffix `a' are related by the symmetry operator (−x + 1, −y + 1, −z + 1).

Figure 2
Part of the crystal structure with N—H⋯O and O—H⋯O hydrogen bonds shown as dashed lines viewed along the [100] direction of the unit cell.

Figure 3
Part of the crystal structure with N—H⋯O, O—H⋯O and weak C—H⋯O hydrogen bonds shown as dashed lines viewed along the [010] direction of the unit cell.

In 1, the octamolybate anion consists of six-coordinate Mo atoms in a distorted octahedral shape bound to oxygen through combinations of terminal, μ₂, μ₃, or μ₅ modes. Relevant bond metrics are reported in Table 2. Most notable, the μ₂-O13 bond lengths are closer to that of terminal [Mo4—O13: 1.759 (4) Å] and higher-coordination environment oxides [Mo2—O13: 2.270 (4) Å], respectively. The atypical bridging Mo—O bond lengths are a hallmark of the β-isomer and have been described as `pseudoterminal' (Bridgeman, 2002). Taken together, these data are consistent with the structural trends present in reported [β-Mo₈O₂₆]⁴⁻ motifs (Bridgeman, 2002).

Table 2
Selected bond lengths (Å)

Mo1—O1	2.340 (4)	Mo3—O1	2.277 (4)
Mo1—O2	2.015 (4)	Mo3—O2ⁱ	2.334 (4)
Mo1—O3	1.893 (4)	Mo3—O4	1.933 (4)
Mo1—O5ⁱ	2.357 (4)	Mo3—O5	1.984 (4)
Mo1—O6	1.696 (4)	Mo3—O10	1.705 (4)
Mo1—O7	1.700 (4)	Mo3—O11	1.699 (4)
Mo2—O1	2.450 (4)	Mo4—O1	2.172 (4)
Mo2—O3	1.901 (4)	Mo4—O1ⁱ	2.368 (4)
Mo2—O4	1.968 (4)	Mo4—O2	1.942 (4)
Mo2—O8	1.699 (4)	Mo4—O5	1.963 (4)
Mo2—O9	1.696 (4)	Mo4—O12	1.692 (4)
Mo2—O13ⁱ	2.270 (4)	Mo4—O13	1.759 (4)
Symmetry code: (i) -x+1, -y+1, -z+1.

The octamolybdate anion, [Mo₈O₂₆]⁴⁻, is common. A search of the Cambridge Structural Database (CSD version 5.40 up to May 2019; Groom et al., 2016 ) listed 278 deposited structures. However, the cis-[bis(2-N,N-dimethylammonium)ethyl ether]²⁺ cation reported here is the first crystallographic example in the literature.

Synthesis and crystallization

Synthesis of the title complex (1): All reagents were purchased from Sigma–Aldrich and used without further purification. MoO₃ (5.0 g, 34.7 mmol) and bis[2-(N,N-dimethylamino)ethyl] ether (13.1 ml, 69.4 mmol) were loaded into a 250 ml round-bottom flask equipped with a magnetic stir bar and diluted with 100 ml of H₂O. The resulting mint-green mixture was heated to 373 K. After 20 minutes the reaction presented as a colorless solution and was cooled to room temperature. The solution was transferred to a 500 ml beaker and diluted with 2-propanol (300 ml), resulting in the formation of a fine colorless precipitate. The solid was allowed to settle, the mother liquor decanted off, and the white solid collected and dried under reduced pressure at 333 K. ¹H NMR (400 MHz, D₂O) in p.p.m.: δ = 4.79 (s, 6H), 3.92 (t, 5.34 Hz, 4H), 3.42 (t, 5.34 Hz, 4H), 2.96 (s, 12H). ¹³C NMR (100 MHz, D₂O) in p.p.m.: δ = 64.40, 56.78, 43.26.

The title complex (1) precipitated as colorless crystals from a D₂O solution stored inside of an NMR tube for three days.

Refinement

Crystal data, data collection and structure refinement details are summarized in Table 3.

Table 3
Experimental details

Crystal data
Chemical formula	(C₈H₂₂N₂O)₂[Mo₈O₂₆]·2D₂O
M_r	1548.13
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	100
a, b, c (Å)	10.139 (3), 11.350 (3), 17.815 (5)
β (°)	96.773 (3)
V (Å³)	2035.7 (9)
Z	2
Radiation type	Mo Kα
μ (mm⁻¹)	2.48
Crystal size (mm)	0.28 × 0.23 × 0.02

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2017 )
T_min, T_max	0.581, 0.646
No. of measured, independent and observed [I > 2σ(I)] reflections	8296, 3652, 2992
R_int	0.029
(sin θ/λ)_max (Å⁻¹)	0.603

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.032, 0.074, 1.08
No. of reflections	3652
No. of parameters	269
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.75, −0.88
Computer programs: APEX3 and SAINT (Bruker, 2017), SHELXS97 (Sheldrick, 2008 ), SHELXL2016 (Sheldrick, 2015 ), PLATON (Spek, 2009 ) and OLEX2 (Dolomanov et al., 2009 ).

Structural data

CCDC reference: 1965627

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2414314619015360/lh4048sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2414314619015360/lh4048Isup2.hkl

checkCIF report

Computing details top

Data collection: APEX3 (Bruker, 2017); cell refinement: SAINT (Bruker, 2017); data reduction: SAINT (Bruker, 2017); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2016 (Sheldrick, 2015); molecular graphics: PLATON (Spek, 2009); software used to prepare material for publication: OLEX2 (Dolomanov et al., 2009).

[Oxybis(ethane-1,2-diyl)]bis(dimethylammonium) octamolybdate dihydrate top

Crystal data top

(C₈H₂₂N₂O)₂[Mo₈O₂₆]·2D₂O	F(000) = 1496
M_r = 1548.13	D_x = 2.526 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
a = 10.139 (3) Å	Cell parameters from 4105 reflections
b = 11.350 (3) Å	θ = 2.2–25.4°
c = 17.815 (5) Å	µ = 2.48 mm⁻¹
β = 96.773 (3)°	T = 100 K
V = 2035.7 (9) Å³	Block, colourless
Z = 2	0.28 × 0.23 × 0.02 mm

Data collection top

Bruker APEXII CCD diffractometer	2992 reflections with I > 2σ(I)
Detector resolution: 8.258 pixels mm^-1	R_int = 0.029
φ and ω scans	θ_max = 25.4°, θ_min = 2.1°
Absorption correction: multi-scan (SADABS; Bruker, 2017)	h = −10→12
T_min = 0.581, T_max = 0.646	k = −9→13
8296 measured reflections	l = −21→19
3652 independent reflections

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.032	H-atom parameters constrained
wR(F²) = 0.074	w = 1/[σ²(F_o²) + (0.0204P)² + 11.0569P] where P = (F_o² + 2F_c²)/3
S = 1.08	(Δ/σ)_max = 0.001
3652 reflections	Δρ_max = 0.75 e Å⁻³
269 parameters	Δρ_min = −0.88 e Å⁻³
0 restraints

Special details top

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

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

	x	y	z	U_iso*/U_eq
Mo4	0.51222 (5)	0.56859 (4)	0.59121 (2)	0.00664 (12)
Mo3	0.57308 (5)	0.29183 (4)	0.58295 (2)	0.00758 (12)
Mo2	0.27674 (5)	0.24855 (5)	0.49345 (3)	0.00926 (13)
Mo1	0.21926 (5)	0.52804 (5)	0.50414 (3)	0.00963 (13)
O5	0.6544 (4)	0.4504 (3)	0.59792 (19)	0.0083 (8)
O4	0.4575 (4)	0.1866 (3)	0.52022 (19)	0.0082 (8)
O1	0.4160 (4)	0.4202 (3)	0.53033 (19)	0.0081 (8)
O2	0.3639 (4)	0.6471 (3)	0.53276 (19)	0.0078 (8)
O3	0.1739 (4)	0.3814 (3)	0.45750 (19)	0.0090 (8)
O15	0.5610 (4)	0.0398 (4)	0.4110 (2)	0.0102 (9)
D15A	0.538031	0.090272	0.443795	0.015*
D15B	0.552187	−0.028589	0.431848	0.015*
O13	0.6163 (4)	0.6926 (3)	0.6051 (2)	0.0102 (8)
O7	0.1035 (4)	0.6188 (4)	0.4579 (2)	0.0138 (9)
O14	0.6350 (4)	0.1851 (4)	0.2749 (2)	0.0138 (9)
O11	0.7115 (4)	0.2063 (4)	0.5948 (2)	0.0127 (9)
O9	0.2025 (4)	0.1352 (4)	0.4428 (2)	0.0161 (9)
O10	0.5105 (4)	0.2820 (4)	0.6675 (2)	0.0116 (9)
O8	0.2277 (4)	0.2344 (4)	0.5810 (2)	0.0162 (9)
O12	0.4551 (4)	0.5481 (4)	0.6757 (2)	0.0117 (9)
O6	0.1744 (4)	0.5114 (4)	0.5923 (2)	0.0148 (9)
N1	0.8289 (5)	0.1047 (4)	0.3826 (2)	0.0108 (10)
H1	0.731353	0.088198	0.377628	0.013*
N2	0.4038 (5)	0.0472 (4)	0.2666 (3)	0.0120 (11)
H2	0.465967	0.050370	0.314483	0.014*
C4	0.5429 (6)	0.1940 (6)	0.2073 (3)	0.0163 (14)
H4A	0.567447	0.138138	0.168577	0.020*
H4B	0.543593	0.274796	0.186460	0.020*
C6	0.8473 (6)	0.2142 (6)	0.3394 (3)	0.0159 (13)
H6A	0.942746	0.224333	0.334054	0.019*
H6B	0.818449	0.282736	0.367715	0.019*
C2	0.4473 (7)	−0.0508 (6)	0.2199 (3)	0.0221 (15)
H2A	0.385925	−0.057648	0.173291	0.033*
H2B	0.447599	−0.124628	0.248378	0.033*
H2C	0.536992	−0.034577	0.207200	0.033*
C5	0.7685 (6)	0.2105 (6)	0.2617 (3)	0.0185 (14)
H5A	0.773187	0.287257	0.235703	0.022*
H5B	0.802965	0.148390	0.230206	0.022*
C8	0.8742 (6)	0.1196 (6)	0.4648 (3)	0.0172 (14)
H8A	0.969481	0.137400	0.471856	0.026*
H8B	0.857809	0.046710	0.491716	0.026*
H8C	0.825183	0.184516	0.484942	0.026*
C3	0.4072 (6)	0.1646 (6)	0.2288 (3)	0.0153 (13)
H3A	0.380344	0.226151	0.263347	0.018*
H3B	0.342107	0.164899	0.182807	0.018*
C7	0.8937 (7)	0.0006 (6)	0.3518 (4)	0.0244 (16)
H7A	0.866396	−0.005198	0.297311	0.037*
H7B	0.866965	−0.070964	0.376808	0.037*
H7C	0.990385	0.009487	0.361060	0.037*
C1	0.2683 (6)	0.0247 (6)	0.2869 (3)	0.0209 (15)
H1A	0.205718	0.018943	0.240680	0.031*
H1B	0.241766	0.089540	0.318142	0.031*
H1C	0.267874	−0.049343	0.315157	0.031*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Mo4	0.0060 (3)	0.0080 (3)	0.0061 (2)	−0.0005 (2)	0.00142 (17)	−0.00017 (18)
Mo3	0.0070 (3)	0.0078 (3)	0.0080 (2)	−0.0009 (2)	0.00073 (18)	0.00107 (19)
Mo2	0.0070 (3)	0.0099 (3)	0.0112 (2)	−0.0009 (2)	0.00251 (18)	0.0000 (2)
Mo1	0.0070 (3)	0.0103 (3)	0.0118 (2)	−0.0009 (2)	0.00221 (19)	−0.0002 (2)
O5	0.009 (2)	0.008 (2)	0.0078 (17)	−0.0009 (16)	0.0008 (15)	0.0025 (15)
O4	0.007 (2)	0.008 (2)	0.0096 (18)	0.0003 (16)	0.0029 (15)	−0.0001 (15)
O1	0.008 (2)	0.009 (2)	0.0073 (17)	−0.0017 (16)	0.0010 (15)	−0.0002 (15)
O2	0.007 (2)	0.005 (2)	0.0108 (18)	−0.0014 (16)	0.0003 (15)	0.0010 (15)
O3	0.007 (2)	0.009 (2)	0.0107 (18)	0.0000 (16)	0.0007 (15)	0.0011 (16)
O15	0.011 (2)	0.008 (2)	0.0122 (19)	0.0018 (18)	0.0033 (16)	−0.0002 (16)
O13	0.007 (2)	0.012 (2)	0.0113 (18)	−0.0006 (17)	0.0012 (15)	−0.0023 (16)
O7	0.011 (2)	0.013 (2)	0.018 (2)	−0.0020 (18)	0.0013 (16)	0.0032 (18)
O14	0.009 (2)	0.021 (3)	0.0116 (19)	−0.0033 (18)	0.0017 (16)	0.0065 (17)
O11	0.009 (2)	0.014 (2)	0.0151 (19)	−0.0011 (17)	−0.0002 (16)	−0.0001 (17)
O9	0.010 (2)	0.018 (3)	0.021 (2)	−0.0008 (18)	0.0049 (17)	−0.0042 (18)
O10	0.015 (2)	0.012 (2)	0.0082 (18)	−0.0027 (18)	0.0037 (16)	0.0010 (16)
O8	0.016 (2)	0.020 (3)	0.014 (2)	−0.0002 (19)	0.0061 (17)	0.0020 (18)
O12	0.015 (2)	0.013 (2)	0.0075 (18)	0.0002 (18)	0.0039 (16)	0.0027 (16)
O6	0.011 (2)	0.016 (2)	0.018 (2)	0.0006 (18)	0.0059 (16)	−0.0006 (18)
N1	0.008 (3)	0.012 (3)	0.013 (2)	−0.001 (2)	0.0044 (19)	0.000 (2)
N2	0.013 (3)	0.011 (3)	0.012 (2)	−0.002 (2)	0.0012 (19)	−0.001 (2)
C4	0.019 (3)	0.017 (4)	0.013 (3)	−0.002 (3)	0.001 (2)	0.003 (3)
C6	0.013 (3)	0.017 (4)	0.018 (3)	−0.004 (3)	0.003 (2)	0.002 (3)
C2	0.034 (4)	0.014 (4)	0.017 (3)	0.002 (3)	−0.002 (3)	0.001 (3)
C5	0.016 (3)	0.020 (4)	0.020 (3)	−0.005 (3)	0.004 (3)	0.008 (3)
C8	0.010 (3)	0.028 (4)	0.014 (3)	0.000 (3)	0.001 (2)	−0.002 (3)
C3	0.015 (3)	0.017 (3)	0.013 (3)	0.005 (3)	−0.002 (2)	0.003 (2)
C7	0.034 (4)	0.019 (4)	0.022 (3)	0.003 (3)	0.011 (3)	−0.006 (3)
C1	0.014 (3)	0.033 (4)	0.016 (3)	−0.009 (3)	0.003 (3)	0.004 (3)

Geometric parameters (Å, º) top

Mo1—O1	2.340 (4)	N1—H1	1.0000
Mo1—O2	2.015 (4)	N1—C6	1.485 (7)
Mo1—O3	1.893 (4)	N1—C8	1.493 (7)
Mo1—O5ⁱ	2.357 (4)	N1—C7	1.487 (8)
Mo1—O6	1.696 (4)	N2—H2	1.0000
Mo1—O7	1.700 (4)	N2—C2	1.486 (8)
Mo2—O1	2.450 (4)	N2—C3	1.494 (8)
Mo2—O3	1.901 (4)	N2—C1	1.484 (7)
Mo2—O4	1.968 (4)	C4—H4A	0.9900
Mo2—O8	1.699 (4)	C4—H4B	0.9900
Mo2—O9	1.696 (4)	C4—C3	1.509 (8)
Mo2—O13ⁱ	2.270 (4)	C6—H6A	0.9900
Mo3—O1	2.277 (4)	C6—H6B	0.9900
Mo3—O2ⁱ	2.334 (4)	C6—C5	1.516 (7)
Mo3—O4	1.933 (4)	C2—H2A	0.9800
Mo3—O5	1.984 (4)	C2—H2B	0.9800
Mo3—O10	1.705 (4)	C2—H2C	0.9800
Mo3—O11	1.699 (4)	C5—H5A	0.9900
Mo4—O1	2.172 (4)	C5—H5B	0.9900
Mo4—O1ⁱ	2.368 (4)	C8—H8A	0.9800
Mo4—O2	1.942 (4)	C8—H8B	0.9800
Mo4—O5	1.963 (4)	C8—H8C	0.9800
Mo4—O12	1.692 (4)	C3—H3A	0.9900
Mo4—O13	1.759 (4)	C3—H3B	0.9900
Mo4—Mo3	3.2081 (11)	C7—H7A	0.9800
Mo4—Mo1	3.2177 (9)	C7—H7B	0.9800
O15—D15A	0.8701	C7—H7C	0.9800
O15—D15B	0.8698	C1—H1A	0.9800
O14—C4	1.437 (6)	C1—H1B	0.9800
O14—C5	1.430 (7)	C1—H1C	0.9800

Mo3—Mo4—Mo1	90.539 (19)	O6—Mo1—O3	103.34 (18)
O5—Mo4—Mo3	35.86 (11)	O6—Mo1—O7	105.74 (19)
O5—Mo4—Mo1	124.14 (11)	Mo4—O5—Mo3	108.74 (17)
O5—Mo4—O1	77.51 (15)	Mo4—O5—Mo1ⁱ	110.13 (16)
O5—Mo4—O1ⁱ	77.85 (14)	Mo3—O5—Mo1ⁱ	104.21 (16)
O1—Mo4—Mo3	45.18 (10)	Mo3—O4—Mo2	113.77 (19)
O1ⁱ—Mo4—Mo3	85.93 (9)	Mo4—O1—Mo4ⁱ	104.28 (15)
O1—Mo4—Mo1	46.64 (10)	Mo4—O1—Mo3	92.26 (13)
O1ⁱ—Mo4—Mo1	86.14 (9)	Mo4—O1—Mo2	164.06 (18)
O1—Mo4—O1ⁱ	75.72 (15)	Mo4ⁱ—O1—Mo2	91.55 (12)
O2—Mo4—Mo3	124.45 (11)	Mo4—O1—Mo1	90.93 (14)
O2—Mo4—Mo1	36.36 (11)	Mo3—O1—Mo4ⁱ	97.77 (14)
O2—Mo4—O5	149.67 (15)	Mo3—O1—Mo2	87.39 (13)
O2—Mo4—O1ⁱ	77.70 (14)	Mo3—O1—Mo1	162.78 (18)
O2—Mo4—O1	79.29 (15)	Mo1—O1—Mo4ⁱ	97.84 (13)
O13—Mo4—Mo3	132.42 (13)	Mo1—O1—Mo2	84.95 (12)
O13—Mo4—Mo1	133.35 (12)	Mo4—O2—Mo3ⁱ	109.56 (17)
O13—Mo4—O5	96.57 (17)	Mo4—O2—Mo1	108.81 (18)
O13—Mo4—O1	156.57 (16)	Mo1—O2—Mo3ⁱ	104.03 (14)
O13—Mo4—O1ⁱ	80.88 (15)	Mo1—O3—Mo2	117.03 (18)
O13—Mo4—O2	97.00 (16)	D15A—O15—D15B	104.5
O12—Mo4—Mo3	89.67 (14)	Mo4—O13—Mo2ⁱ	117.40 (18)
O12—Mo4—Mo1	90.91 (13)	C5—O14—C4	112.4 (4)
O12—Mo4—O5	100.26 (17)	C6—N1—H1	107.1
O12—Mo4—O1	99.04 (17)	C6—N1—C8	111.7 (5)
O12—Mo4—O1ⁱ	174.68 (17)	C6—N1—C7	112.7 (5)
O12—Mo4—O2	102.45 (17)	C8—N1—H1	107.1
O12—Mo4—O13	104.33 (18)	C7—N1—H1	107.1
O5—Mo3—Mo4	35.40 (11)	C7—N1—C8	110.7 (5)
O5—Mo3—O1	74.60 (14)	C2—N2—H2	107.8
O5—Mo3—O2ⁱ	72.35 (14)	C2—N2—C3	113.0 (5)
O4—Mo3—Mo4	121.63 (11)	C3—N2—H2	107.8
O4—Mo3—O5	148.38 (15)	C1—N2—H2	107.8
O4—Mo3—O1	79.08 (14)	C1—N2—C2	110.6 (5)
O4—Mo3—O2ⁱ	83.29 (14)	C1—N2—C3	109.5 (5)
O1—Mo3—Mo4	42.56 (9)	O14—C4—H4A	110.3
O1—Mo3—O2ⁱ	72.39 (13)	O14—C4—H4B	110.3
O2ⁱ—Mo3—Mo4	79.86 (9)	O14—C4—C3	107.0 (4)
O11—Mo3—Mo4	135.57 (14)	H4A—C4—H4B	108.6
O11—Mo3—O5	100.21 (17)	C3—C4—H4A	110.3
O11—Mo3—O4	98.89 (17)	C3—C4—H4B	110.3
O11—Mo3—O1	160.74 (16)	N1—C6—H6A	109.3
O11—Mo3—O2ⁱ	88.35 (16)	N1—C6—H6B	109.3
O11—Mo3—O10	103.94 (18)	N1—C6—C5	111.4 (5)
O10—Mo3—Mo4	85.97 (14)	H6A—C6—H6B	108.0
O10—Mo3—O5	97.61 (17)	C5—C6—H6A	109.3
O10—Mo3—O4	101.94 (17)	C5—C6—H6B	109.3
O10—Mo3—O1	95.18 (16)	N2—C2—H2A	109.5
O10—Mo3—O2ⁱ	165.54 (17)	N2—C2—H2B	109.5
O4—Mo2—O1	74.23 (14)	N2—C2—H2C	109.5
O4—Mo2—O13ⁱ	77.07 (14)	H2A—C2—H2B	109.5
O3—Mo2—O4	145.37 (16)	H2A—C2—H2C	109.5
O3—Mo2—O1	74.65 (14)	H2B—C2—H2C	109.5
O3—Mo2—O13ⁱ	78.41 (15)	O14—C5—C6	105.2 (5)
O13ⁱ—Mo2—O1	70.16 (13)	O14—C5—H5A	110.7
O9—Mo2—O4	101.54 (17)	O14—C5—H5B	110.7
O9—Mo2—O1	162.10 (16)	C6—C5—H5A	110.7
O9—Mo2—O3	103.37 (18)	C6—C5—H5B	110.7
O9—Mo2—O13ⁱ	91.97 (17)	H5A—C5—H5B	108.8
O9—Mo2—O8	104.9 (2)	N1—C8—H8A	109.5
O8—Mo2—O4	96.25 (17)	N1—C8—H8B	109.5
O8—Mo2—O1	92.90 (17)	N1—C8—H8C	109.5
O8—Mo2—O3	100.13 (18)	H8A—C8—H8B	109.5
O8—Mo2—O13ⁱ	162.85 (17)	H8A—C8—H8C	109.5
O5ⁱ—Mo1—Mo4	78.60 (9)	H8B—C8—H8C	109.5
O1—Mo1—Mo4	42.44 (9)	N2—C3—C4	112.4 (5)
O1—Mo1—O5ⁱ	71.35 (13)	N2—C3—H3A	109.1
O2—Mo1—Mo4	34.83 (10)	N2—C3—H3B	109.1
O2—Mo1—O5ⁱ	71.34 (14)	C4—C3—H3A	109.1
O2—Mo1—O1	73.89 (14)	C4—C3—H3B	109.1
O3—Mo1—Mo4	120.00 (11)	H3A—C3—H3B	107.9
O3—Mo1—O5ⁱ	83.03 (15)	N1—C7—H7A	109.5
O3—Mo1—O1	77.57 (14)	N1—C7—H7B	109.5
O3—Mo1—O2	146.37 (16)	N1—C7—H7C	109.5
O7—Mo1—Mo4	133.80 (14)	H7A—C7—H7B	109.5
O7—Mo1—O5ⁱ	88.28 (16)	H7A—C7—H7C	109.5
O7—Mo1—O1	159.59 (16)	H7B—C7—H7C	109.5
O7—Mo1—O2	99.00 (17)	N2—C1—H1A	109.5
O7—Mo1—O3	101.67 (17)	N2—C1—H1B	109.5
O6—Mo1—Mo4	84.40 (13)	N2—C1—H1C	109.5
O6—Mo1—O5ⁱ	162.77 (16)	H1A—C1—H1B	109.5
O6—Mo1—O1	94.14 (16)	H1A—C1—H1C	109.5
O6—Mo1—O2	96.14 (17)	H1B—C1—H1C	109.5

Symmetry code: (i) −x+1, −y+1, −z+1.

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···O14	1.00	2.26	2.737 (6)	108
N1—H1···O15	1.00	1.97	2.916 (7)	157
N2—H2···O14	1.00	2.46	2.808 (7)	100
N2—H2···O15	1.00	1.87	2.863 (6)	170
O15—D15A···O4	0.87	1.99	2.854 (5)	170
O15—D15B···O4ⁱⁱ	0.87	1.99	2.863 (6)	177
C1—H1A···O5ⁱⁱⁱ	0.98	2.56	3.440 (6)	149
C1—H1B···O9	0.98	2.36	3.189 (7)	142
C1—H1C···O11ⁱⁱ	0.98	2.39	3.355 (8)	168
C2—H2A···O3^iv	0.98	2.44	3.343 (7)	153
C2—H2B···O10ⁱⁱ	0.98	2.34	3.300 (8)	167
C3—H3A···O13ⁱ	0.99	2.52	3.407 (7)	150
C3—H3B···O11ⁱⁱⁱ	0.99	2.42	3.266 (7)	143
C4—H4A···O6^v	0.99	2.50	3.472 (8)	167
C6—H6B···O6ⁱ	0.99	2.44	3.360 (8)	154
C7—H7A···O12^v	0.98	2.49	3.316 (8)	142
C7—H7B···O8ⁱⁱ	0.98	2.26	3.227 (8)	170
C8—H8A···O9^vi	0.98	2.48	3.402 (7)	157
C8—H8B···O9ⁱⁱ	0.98	2.48	3.461 (8)	176
C8—H8C···O11	0.98	2.40	3.155 (7)	134
C8—H8C···O7ⁱ	0.98	2.52	3.270 (8)	133

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

Selected bond lengths (Å) top

Mo-O	(Å)	Mo-O	(Å)
Mo1-O1	2.340 (4)	Mo3-O1	2.277 (4)
Mo1-O2	2.015 (4)	Mo3-O2#1	2.334 (4)
Mo1-O3	1.893 (4)	Mo3-O4	1.933 (4)
Mo1-O5#1	2.357 (4)	Mo3-O5	1.984 (4)
Mo1-O6	1.696 (4)	Mo3-O10	1.705 (4)
Mo1-O7	1.700 (4)	Mo3-O11	1.699 (4)
Mo2-O1	2.450 (4)	Mo4-O1	2.172 (4)
Mo2-O3	1.901 (4)	Mo4-O1#1	2.368 (4)
Mo2-O4	1.968 (4)	Mo4-O2	1.942 (4)
Mo2-O8	1.699 (4)	Mo4-O5	1.963 (4)
Mo2-O9	1.696 (4)	Mo4-O12	1.692 (4)
Mo2-O13#1	2.270 (4)	Mo4-O13	1.759 (4)

Symmetry transformations used to generate equivalent atoms: #1 -x+1,-y+1,-z+1

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