Bromido-1κBr-tricarbonyl-2κ³C-(2η⁵-cyclo­penta­dien­yl)molybdenum(I)tungsten(I)(W—Mo)

The title compound, [WMoBr(C₅H₅)(CO)₃], is built up from a pseudo-square-pyramidal piano-stool coordination around the Mo atom, the important geometry being Mo—W = 2.6872 (7) Å, W—Br = 2.5591 (9) Å and Mo—W—Br = 158.35 (3)°.

Key indicators

• Single-crystal X-ray study
• T = 100 K
• Mean [sigma](C-C) = 0.017 Å
• R factor = 0.031
• wR factor = 0.069
• Data-to-parameter ratio = 21.0

checkCIF/PLATON results

No syntax errors found





Alert level B
PLAT213_ALERT_2_B Atom C6      has ADP max/min Ratio .............       4.30 prola

Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR) is > 1.10
            Tmin and Tmax reported:      0.251     0.347
            Tmin and Tmax expected:      0.206     0.348
            RR =      1.223
            Please check that your absorption correction is appropriate.
PLAT060_ALERT_3_C Ratio Tmax/Tmin (Exp-to-Rep) (too) Large .......       1.22
PLAT213_ALERT_2_C Atom C5      has ADP max/min Ratio .............       3.30 oblat
PLAT213_ALERT_2_C Atom C7      has ADP max/min Ratio .............       3.70 prola
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  W1     -   Br1     ..       8.51 su
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for         C7
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        Mo1
PLAT342_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...         17
PLAT850_ALERT_2_C Check Flack Parameter Exact Value 0.00 and su ..       0.01

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           28.29
           From the CIF: _reflns_number_total               2673
           Count of symmetry unique reflns         1555
           Completeness (_total/calc)            171.90%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured      1118
           Fraction of Friedel pairs measured     0.719
           Are heavy atom types Z>Si present        yes

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

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

---

S1. Comment

The compound I was a by-product of a study on the functionalization of paraffins using transition metals. The functionalized compounds have potential applications in catalysis and organic syntheses (Changamu et al., 2006). The compound I is similar to the reported structure of (η⁵-C₅H₅(CO)₃MoHgCl (Bueno et al., 1981), Albright et al. (1978). The bond distances of W—Mo, 2.6872 (7) Å and W—Br, 2.5591 (9) Å are comparable to Hg—Mo, 2.693 (30) Å and Hg—Cl, 2.437 (8) Å respectively. The slight difference between the bond lenghts involving the halides could be attributed to the difference in electronegativity and hence basicity between bromine and chlorine.The coordination around Mo is a pseudo-square pyramidal piano stool arrangement.(Fig. 1)

Related literature

For related literature, see Albright et al. (1978); Bueno & Churchill (1981); Changamu et al. (2006); Friedrich et al. (2004).

S2. Experimental

The compound I was prepared according to a reported procedure (Friedrich et al., 2004) and crystals were grown by slow evaporation of a mixture of dichloromethane and hexane at 263 K.

S3. Refinement

Hydrogen atoms were treated as riding on their parent C atoms with C–H = 0.95 Å and U_iso(H) = 1.2 U_eq(C).

Computing details

Data collection: SMART (Bruker, 2002); 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: X-SEED (Barbour 2001); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008) and PLATON (Spek, 2001).

Figures

Fig. 1. Molecular structure of the title complex showing the atom numbering scheme. Ellipsoids are drawn at the 50% probability level.

Bromido-1κBr-tricarbonyl-2κ³C-(2η⁵- cyclopentadienyl)molybdenum(I)tungsten(I)(W—Mo)

Crystal data

[WMoBr(C5H5)(CO)3]	Dx = 3.051 Mg m^−3
Mr = 508.82	Mo Kα radiation, λ = 0.71073 Å
Tetragonal, P421c	Cell parameters from 2238 reflections
Hall symbol: P -4 2n	θ = 2.2–25.5°
a = 11.9375 (9) Å	µ = 15.09 mm^−1
c = 15.546 (2) Å	T = 100 K
V = 2215.4 (4) Å^3	Block, yellow
Z = 8	0.11 × 0.10 × 0.07 mm
F(000) = 1824

Data collection

Bruker APEX CCD area-detector diffractometer	2673 independent reflections
Radiation source: fine-focus sealed tube	2497 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.048
ω scans	θmax = 28.3°, θmin = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2002)	h = −15→14
Tmin = 0.251, Tmax = 0.347	k = −8→15
13298 measured reflections	l = −20→18

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.030	H-atom parameters constrained
wR(F^2) = 0.069	w = 1/[σ^2(Fo^2) + (0.0238P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.02	(Δ/σ)max = 0.001
2673 reflections	Δρmax = 1.31 e Å^−3
127 parameters	Δρmin = −0.72 e Å^−3
0 restraints	Absolute structure: Flack (1983), 1118 Friedel pairs
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.00 (1)

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
W1	0.64476 (3)	0.39974 (3)	0.89630 (2)	0.01742 (9)
Mo1	0.73518 (6)	0.20182 (6)	0.85204 (5)	0.01833 (16)
Br1	0.62054 (7)	0.61253 (7)	0.90359 (5)	0.01974 (17)
O1	0.5124 (6)	0.1402 (6)	0.9503 (5)	0.0480 (19)
O2	0.6348 (5)	0.0161 (6)	0.7340 (4)	0.0402 (17)
O3	0.6948 (5)	0.3305 (6)	0.6794 (4)	0.0330 (16)
C1	0.5937 (8)	0.1680 (7)	0.9122 (6)	0.031 (2)
C2	0.6724 (7)	0.0833 (7)	0.7766 (6)	0.026 (2)
C3	0.7057 (7)	0.2868 (8)	0.7450 (6)	0.027 (2)
C4	0.8467 (10)	0.1507 (11)	0.9698 (7)	0.047 (3)
H4	0.8151	0.1245	1.0222	0.057*
C5	0.8729 (8)	0.0831 (8)	0.9024 (7)	0.038 (2)
H5	0.8622	0.0043	0.8996	0.046*
C6	0.9203 (7)	0.1535 (11)	0.8354 (6)	0.044 (3)
H6	0.9468	0.1308	0.7805	0.052*
C7	0.9181 (9)	0.2684 (10)	0.8715 (9)	0.059 (4)
H7	0.9431	0.3359	0.8455	0.071*
C8	0.8694 (10)	0.2533 (11)	0.9549 (7)	0.052 (3)
H8	0.8557	0.3126	0.9943	0.063*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
W1	0.01888 (17)	0.01447 (16)	0.01889 (15)	0.00532 (12)	0.00265 (14)	−0.00152 (14)
Mo1	0.0158 (3)	0.0170 (3)	0.0222 (3)	0.0033 (3)	0.0015 (3)	−0.0020 (3)
Br1	0.0214 (4)	0.0168 (4)	0.0209 (4)	0.0015 (3)	0.0032 (3)	0.0010 (3)
O1	0.036 (4)	0.032 (4)	0.076 (5)	0.006 (3)	0.029 (4)	0.011 (4)
O2	0.034 (4)	0.033 (4)	0.054 (4)	0.006 (3)	−0.008 (3)	−0.016 (3)
O3	0.035 (4)	0.045 (4)	0.019 (3)	0.007 (3)	−0.005 (3)	0.002 (3)
C1	0.032 (5)	0.015 (4)	0.045 (6)	0.009 (4)	0.004 (5)	0.003 (4)
C2	0.020 (5)	0.020 (5)	0.037 (5)	0.003 (4)	0.006 (4)	−0.012 (4)
C3	0.020 (5)	0.033 (5)	0.029 (5)	0.002 (4)	−0.004 (4)	−0.008 (4)
C4	0.042 (6)	0.069 (8)	0.030 (5)	−0.002 (7)	0.000 (5)	0.002 (6)
C5	0.033 (5)	0.030 (5)	0.053 (6)	0.015 (4)	−0.025 (5)	0.004 (5)
C6	0.016 (5)	0.091 (9)	0.024 (5)	0.028 (5)	−0.007 (4)	−0.007 (5)
C7	0.025 (6)	0.043 (7)	0.110 (11)	−0.014 (5)	−0.036 (6)	0.048 (7)
C8	0.037 (7)	0.058 (8)	0.061 (7)	0.015 (6)	−0.016 (5)	−0.035 (7)

Geometric parameters (Å, º)

W1—Br1	2.5591 (9)	O3—C3	1.152 (12)
W1—Mo1	2.6872 (7)	C4—C8	1.276 (17)
Mo1—C1	1.972 (10)	C4—C5	1.359 (15)
Mo1—C3	1.980 (10)	C4—H4	0.9500
Mo1—C2	1.985 (8)	C5—C6	1.453 (15)
Mo1—C6	2.298 (8)	C5—H5	0.9500
Mo1—C5	2.307 (8)	C6—C7	1.482 (17)
Mo1—C7	2.344 (10)	C6—H6	0.9500
Mo1—C4	2.345 (12)	C7—C8	1.433 (16)
Mo1—C8	2.346 (10)	C7—H7	0.9500
O1—C1	1.184 (11)	C8—H8	0.9500
O2—C2	1.132 (10)
Br1—W1—Mo1	158.35 (3)	C4—Mo1—W1	104.9 (3)
C1—Mo1—C3	110.5 (4)	C8—Mo1—W1	82.5 (3)
C1—Mo1—C2	79.1 (4)	O1—C1—Mo1	175.0 (8)
C3—Mo1—C2	78.5 (4)	O2—C2—Mo1	178.9 (8)
C1—Mo1—C6	145.6 (4)	O3—C3—Mo1	174.3 (8)
C3—Mo1—C6	101.8 (4)	C8—C4—C5	112.4 (11)
C2—Mo1—C6	96.8 (4)	C8—C4—Mo1	74.3 (7)
C1—Mo1—C5	108.9 (4)	C5—C4—Mo1	71.5 (6)
C3—Mo1—C5	136.6 (4)	C8—C4—H4	123.8
C2—Mo1—C5	91.8 (4)	C5—C4—H4	123.8
C6—Mo1—C5	36.8 (4)	Mo1—C4—H4	121.9
C1—Mo1—C7	143.7 (4)	C4—C5—C6	107.4 (10)
C3—Mo1—C7	95.8 (4)	C4—C5—Mo1	74.5 (6)
C2—Mo1—C7	132.1 (4)	C6—C5—Mo1	71.3 (5)
C6—Mo1—C7	37.2 (4)	C4—C5—H5	126.3
C5—Mo1—C7	60.0 (4)	C6—C5—H5	126.3
C1—Mo1—C4	93.6 (4)	Mo1—C5—H5	119.8
C3—Mo1—C4	152.9 (4)	C5—C6—C7	104.9 (9)
C2—Mo1—C4	119.4 (4)	C5—C6—Mo1	71.9 (5)
C6—Mo1—C4	58.5 (4)	C7—C6—Mo1	73.0 (5)
C5—Mo1—C4	34.0 (4)	C5—C6—H6	127.6
C7—Mo1—C4	57.2 (4)	C7—C6—H6	127.6
C1—Mo1—C8	108.4 (4)	Mo1—C6—H6	119.6
C3—Mo1—C8	124.1 (4)	C8—C7—C6	103.5 (9)
C2—Mo1—C8	148.0 (4)	C8—C7—Mo1	72.3 (6)
C6—Mo1—C8	59.1 (4)	C6—C7—Mo1	69.7 (5)
C5—Mo1—C8	56.1 (4)	C8—C7—H7	128.2
C7—Mo1—C8	35.6 (4)	C6—C7—H7	128.2
C4—Mo1—C8	31.6 (4)	Mo1—C7—H7	121.7
C1—Mo1—W1	73.4 (2)	C4—C8—C7	111.8 (10)
C3—Mo1—W1	72.1 (3)	C4—C8—Mo1	74.2 (7)
C2—Mo1—W1	128.8 (3)	C7—C8—Mo1	72.1 (6)
C6—Mo1—W1	129.5 (3)	C4—C8—H8	124.1
C5—Mo1—W1	137.7 (3)	C7—C8—H8	124.1
C7—Mo1—W1	92.5 (3)	Mo1—C8—H8	121.1
Br1—W1—Mo1—C1	−172.7 (3)	C8—Mo1—C6—C5	73.6 (7)
Br1—W1—Mo1—C3	−54.0 (3)	W1—Mo1—C6—C5	119.9 (6)
Br1—W1—Mo1—C2	−112.2 (3)	C1—Mo1—C6—C7	−115.9 (9)
Br1—W1—Mo1—C6	36.8 (3)	C3—Mo1—C6—C7	83.9 (7)
Br1—W1—Mo1—C5	87.2 (4)	C2—Mo1—C6—C7	163.6 (6)
Br1—W1—Mo1—C7	41.3 (3)	C5—Mo1—C6—C7	−112.4 (8)
Br1—W1—Mo1—C4	97.9 (3)	C4—Mo1—C6—C7	−76.0 (7)
Br1—W1—Mo1—C8	75.5 (3)	C8—Mo1—C6—C7	−38.9 (6)
C1—Mo1—C4—C8	−120.1 (8)	W1—Mo1—C6—C7	7.4 (7)
C3—Mo1—C4—C8	33.5 (13)	C5—C6—C7—C8	−0.4 (9)
C2—Mo1—C4—C8	160.4 (7)	Mo1—C6—C7—C8	65.0 (7)
C6—Mo1—C4—C8	81.2 (8)	C5—C6—C7—Mo1	−65.4 (6)
C5—Mo1—C4—C8	120.8 (11)	C1—Mo1—C7—C8	8.5 (10)
C7—Mo1—C4—C8	36.9 (7)	C3—Mo1—C7—C8	145.7 (7)
W1—Mo1—C4—C8	−46.3 (8)	C2—Mo1—C7—C8	−134.5 (8)
C1—Mo1—C4—C5	119.1 (7)	C6—Mo1—C7—C8	−112.3 (8)
C3—Mo1—C4—C5	−87.3 (11)	C5—Mo1—C7—C8	−72.6 (7)
C2—Mo1—C4—C5	39.6 (8)	C4—Mo1—C7—C8	−32.7 (6)
C6—Mo1—C4—C5	−39.6 (7)	W1—Mo1—C7—C8	73.4 (7)
C7—Mo1—C4—C5	−83.8 (8)	C1—Mo1—C7—C6	120.8 (8)
C8—Mo1—C4—C5	−120.8 (11)	C3—Mo1—C7—C6	−102.0 (6)
W1—Mo1—C4—C5	−167.1 (6)	C2—Mo1—C7—C6	−22.2 (8)
C8—C4—C5—C6	0.7 (13)	C5—Mo1—C7—C6	39.7 (6)
Mo1—C4—C5—C6	64.2 (6)	C4—Mo1—C7—C6	79.6 (7)
C8—C4—C5—Mo1	−63.4 (10)	C8—Mo1—C7—C6	112.3 (8)
C1—Mo1—C5—C4	−67.1 (8)	W1—Mo1—C7—C6	−174.3 (6)
C3—Mo1—C5—C4	138.6 (7)	C5—C4—C8—C7	−1.0 (14)
C2—Mo1—C5—C4	−146.2 (7)	Mo1—C4—C8—C7	−62.8 (8)
C6—Mo1—C5—C4	115.0 (10)	C5—C4—C8—Mo1	61.8 (9)
C7—Mo1—C5—C4	74.7 (8)	C6—C7—C8—C4	0.9 (12)
C8—Mo1—C5—C4	32.8 (7)	Mo1—C7—C8—C4	64.1 (9)
W1—Mo1—C5—C4	18.7 (9)	C6—C7—C8—Mo1	−63.2 (6)
C1—Mo1—C5—C6	177.9 (6)	C1—Mo1—C8—C4	65.5 (8)
C3—Mo1—C5—C6	23.6 (8)	C3—Mo1—C8—C4	−162.4 (7)
C2—Mo1—C5—C6	98.8 (6)	C2—Mo1—C8—C4	−33.5 (12)
C7—Mo1—C5—C6	−40.2 (6)	C6—Mo1—C8—C4	−79.1 (8)
C4—Mo1—C5—C6	−115.0 (10)	C5—Mo1—C8—C4	−35.3 (7)
C8—Mo1—C5—C6	−82.2 (7)	C7—Mo1—C8—C4	−119.8 (10)
W1—Mo1—C5—C6	−96.2 (7)	W1—Mo1—C8—C4	135.2 (7)
C4—C5—C6—C7	−0.1 (10)	C1—Mo1—C8—C7	−174.7 (7)
Mo1—C5—C6—C7	66.2 (6)	C3—Mo1—C8—C7	−42.6 (8)
C4—C5—C6—Mo1	−66.3 (7)	C2—Mo1—C8—C7	86.3 (11)
C1—Mo1—C6—C5	−3.5 (10)	C6—Mo1—C8—C7	40.7 (6)
C3—Mo1—C6—C5	−163.7 (6)	C5—Mo1—C8—C7	84.5 (7)
C2—Mo1—C6—C5	−84.0 (6)	C4—Mo1—C8—C7	119.8 (10)
C7—Mo1—C6—C5	112.4 (8)	W1—Mo1—C8—C7	−105.0 (7)
C4—Mo1—C6—C5	36.5 (6)