Tricarbon­yl(2-methyl-2-η6-phenyl-1,3-dioxolane)chromium(0)

Duke III, C.B.; Ross, C.R.; Burkey, T.J.

doi:10.1107/S1600536810000759

metal-organic compounds

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ISSN: 2056-9890

Volume 66| Part 2| February 2010| Page m148

https://doi.org/10.1107/S1600536810000759

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Tricarbonyl(2-methyl-2-η⁶-phenyl-1,3-dioxolane)chromium(0)

Charles B. Duke III,^a Charles R. Ross ^b and Theodore J. Burkey ^c ^*

^aDepartment of Pharmaceutical Sciences, University of Tennessee Health Sciences Center, 847 Monroe Avenue, Suite 227A, Memphis, TN 38163, USA, ^bSt. Jude Children's Research Hospital, Department of Structrual Biology, MS311, 332 North Lauderdale, Memphis, TN 38105-2794, USA, and ^cDepartment of Chemistry, University of Memphis, 213 Smith Chemistry Building, Memphis, TN 38152-3550, USA
^*Correspondence e-mail: tburkey@memphis.edu

(Received 17 December 2009; accepted 7 January 2010; online 13 January 2010)

The structure of the title compound, [Cr(C₁₀H₁₂O₂)(CO)₃], is presented. The distorted piano-stool geometry features an off-center Cr(CO)₃ fragment which reduces contact with the dioxolane ring. The dioxolane ring, in twisted conformation, is syn-oriented towards the Cr(CO)₃ moiety.

Related literature

For the synthesis of the title compound, see: Bitterwolf (1988 ); Mahaffy & Pauson (1990 ).

Experimental

Crystal data

[Cr(C₁₀H₁₂O₂)(CO)₃]
M_r = 300.23
Triclinic, $[P \overline 1]$
a = 7.1950 (3) Å
b = 7.2120 (3) Å
c = 13.9235 (6) Å
α = 75.573 (2)°
β = 79.277 (2)°
γ = 62.734 (1)°
V = 619.79 (5) Å³
Z = 2
Cu Kα radiation
μ = 7.74 mm⁻¹
T = 173 K
0.11 × 0.08 × 0.08 mm

Data collection

Bruker Proteum diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2000 ) T_min = 0.489, T_max = 0.587
13788 measured reflections
2163 independent reflections
2066 reflections with I > 2σ(I)
R_int = 0.028

Refinement

R[F² > 2σ(F²)] = 0.028
wR(F²) = 0.072
S = 1.11
2163 reflections
172 parameters
H-atom parameters constrained
Δρ_max = 0.34 e Å⁻³
Δρ_min = −0.19 e Å⁻³

Table 1
Selected geometric parameters (Å, °)

Cr1—C1O	1.837 (2)
Cr1—C3O	1.846 (2)
Cr1—C2O	1.854 (2)
Cr1—C5	2.1942 (18)
Cr1—C6	2.2062 (19)
Cr1—C4	2.2197 (18)
Cr1—C3	2.2248 (18)
Cr1—C2	2.2355 (18)
Cr1—C1	2.2440 (18)
O1C—C1O	1.156 (2)
O3C—C3O	1.150 (2)
O2C—C2O	1.155 (3)

C1O—Cr1—C3O	85.12 (8)
C1O—Cr1—C2O	90.23 (9)
C3O—Cr1—C2O	88.90 (9)

Data collection: PROTEUM2 (Bruker, 2005 ); cell refinement: SAINT (Bruker, 1998 ); 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 ) and RASTER3D (Merritt & Bacon, 1997 ); software used to prepare material for publication: WinGX (Farrugia, 1999 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: https://doi.org/10.1107/S1600536810000759/kp2246sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S1600536810000759/kp2246Isup2.hkl

checkCIF report

Comment top

Synthesized en route to η⁶-acetophenone chromium tricarbonyl, I was formed by treatment of acetophenone ethylene ketal (II) with Cr(CO)₆. Though similar syntheses of the title compound have been previously reported (Bitterwolf, 1981), no structure (Fig. 1) has been previously published. A piano-stool structure, typical of arenechromiumcarbonyls, was found with the sum of the carbonyl C—Cr—C angles of 264.25 (15) °. Rather than above the ring, as would apparently minimize the interaction between the side chain and metal, the dioxolane moiety is oriented towards the Cr(CO)₃ moiety and the benzylic carbon is approximately 6.5 ° out of the plane of the ring. The distorted piano-stool geometry features an off-center Cr(CO)₃ fragment which is offset from the dioxolane moiety; Cr—C distances in the ring average 2.2207 (18) Å with a minimum of 2.1942 (18) Å to C5 opposite the closest Cr-sidechain distance of 3.433 Å to H10B. The largest aniosotropic displacement parameters are on the three carbonyl O atoms which experience the largest motion in the molecule as a function of the Cr—CO moment arm. The packing of I (Fig. 2) with two unit cells in each dimension is given.

Related literature top

For the synthesis of the title compound, see: Bitterwolf (1988) or (1981)?; Mahaffey or Mahaffy & Pauson (1990).

Experimental top

Acetophenone (30.0 ml, 100 mmol) and ethylene glycol (28.0 ml, 500 mmol) were stirred in toluene (100 ml) with p-TsOH (30 mg, 0.17 µmol) for 12 h. Concentration by rotary evaporation and filtration afforded 2 (8.856 g) in 54% yield. The title compound was isolated in 28% yield by the standard literature method (Mahaffey et al., 1990) of treating II with Cr(CO)₆ in refluxing THF/Bu₂O (10%) under a nitrogen environment for 40 h. Solvent removal in vacuo, filtration and subsequent recrystallization from Et₂O/hexanes (approximately 1:3 by volume) produced blocky yellow crystals, from which a crystal suitable for diffractometry was selected.

Structure description top

# Following replaced by publCIF - Mon Apr 3 09:37:38 2006

# Insert blank lines between paragraphs ?

Computing details top

Data collection: PROTEUM2 (Bruker, 2005); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEP-3 (Farrugia, 1997) and RASTER3D (Merritt & Bacon, 1997); software used to prepare material for publication: WinGX (Farrugia, 1999).

Figures top

	Fig. 1. View of I (50% probability displacement ellipsoids) with the dioxolane ring oriented towards the metal center.
	Fig. 2. Packing view slightly off of axis b with two unit cells in each dimension.
	Fig. 3. The reaction scheme for the synthesis of I through II Conditions: a) HOCH₂CH₂OH, PhMe, p-TsOH, 12 h, 25 °C. b) Cr(CO)₆, Bu₂O/THF (10:1), reflux, 40 h.

Tricarbonyl(2-methyl-2-h⁶-phenyl-1,3-dioxolane)chromium(0) top

Crystal data top

[Cr(C₁₀H₁₂O₂)(CO)₃]	Z = 2
M_r = 300.23	F(000) = 308
Triclinic, P1	D_x = 1.609 Mg m⁻³
Hall symbol: -P 1	Cu Kα radiation, λ = 1.54178 Å
a = 7.1950 (3) Å	Cell parameters from 8653 reflections
b = 7.2120 (3) Å	θ = 3.3–68.5°
c = 13.9235 (6) Å	µ = 7.74 mm⁻¹
α = 75.573 (2)°	T = 173 K
β = 79.277 (2)°	Block, yellow
γ = 62.734 (1)°	0.11 × 0.08 × 0.08 mm
V = 619.79 (5) Å³

Data collection top

Bruker Proteum diffractometer	2163 independent reflections
Radiation source: fine-focus rotating anode	2066 reflections with I > 2σ(I)
Osmic mirrors monochromator	R_int = 0.028
Area detector scans	θ_max = 68.7°, θ_min = 3.3°
Absorption correction: multi-scan (SADABS; Bruker, 2000)	h = −8→8
T_min = 0.489, T_max = 0.587	k = −8→8
13788 measured reflections	l = −16→16

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	H-atom parameters constrained
R[F² > 2σ(F²)] = 0.028	w = 1/[σ²(F_o²) + (0.0421P)² + 0.2689P] where P = (F_o² + 2F_c²)/3
wR(F²) = 0.072	(Δ/σ)_max = 0.001
S = 1.11	Δρ_max = 0.34 e Å⁻³
2163 reflections	Δρ_min = −0.19 e Å⁻³
172 parameters

Crystal data top

[Cr(C₁₀H₁₂O₂)(CO)₃]	γ = 62.734 (1)°
M_r = 300.23	V = 619.79 (5) Å³
Triclinic, P1	Z = 2
a = 7.1950 (3) Å	Cu Kα radiation
b = 7.2120 (3) Å	µ = 7.74 mm⁻¹
c = 13.9235 (6) Å	T = 173 K
α = 75.573 (2)°	0.11 × 0.08 × 0.08 mm
β = 79.277 (2)°

Data collection top

Bruker Proteum diffractometer	2163 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2000)	2066 reflections with I > 2σ(I)
T_min = 0.489, T_max = 0.587	R_int = 0.028
13788 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.028	0 restraints
wR(F²) = 0.072	H-atom parameters constrained
S = 1.11	Δρ_max = 0.34 e Å⁻³
2163 reflections	Δρ_min = −0.19 e Å⁻³
172 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.

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

	x	y	z	U_iso*/U_eq
Cr1	0.56963 (4)	0.54830 (4)	0.67821 (2)	0.01624 (12)
O1	0.5396 (2)	0.9647 (2)	0.83565 (10)	0.0215 (3)
O2	0.64557 (19)	0.6261 (2)	0.92482 (9)	0.0200 (3)
O1C	0.9718 (2)	0.2980 (2)	0.77613 (11)	0.0285 (3)
O3C	0.7158 (3)	0.1574 (2)	0.59248 (11)	0.0332 (4)
O2C	0.7899 (3)	0.7234 (2)	0.50035 (13)	0.0394 (4)
C7	0.4720 (3)	0.8035 (3)	0.87807 (14)	0.0189 (4)
C9	0.8237 (3)	0.6734 (3)	0.90280 (15)	0.0223 (4)
H9A	0.9517	0.5501	0.8844	0.027*
H9B	0.8483	0.7142	0.9604	0.027*
C5	0.3036 (3)	0.4871 (3)	0.75700 (15)	0.0212 (4)
H5	0.2921	0.3565	0.7733	0.025*
C1	0.4040 (3)	0.7366 (3)	0.79966 (14)	0.0182 (4)
C2	0.3431 (3)	0.8710 (3)	0.70791 (14)	0.0192 (4)
H2	0.3577	1	0.6907	0.023*
C3O	0.6577 (3)	0.3107 (3)	0.62306 (14)	0.0228 (4)
C10	0.7633 (3)	0.8586 (3)	0.81534 (15)	0.0233 (4)
H10A	0.8305	0.952	0.8144	0.028*
H10B	0.8012	0.8088	0.7512	0.028*
C3	0.2600 (3)	0.8157 (3)	0.64066 (14)	0.0219 (4)
H3	0.2191	0.9075	0.5786	0.026*
C6	0.3853 (3)	0.5420 (3)	0.82357 (14)	0.0189 (4)
H6	0.4285	0.4487	0.885	0.023*
C1O	0.8162 (3)	0.4006 (3)	0.73882 (14)	0.0203 (4)
C4	0.2380 (3)	0.6255 (3)	0.66549 (15)	0.0229 (4)
H4	0.1793	0.5899	0.6211	0.027*
C2O	0.7044 (3)	0.6586 (3)	0.56913 (16)	0.0256 (4)
C8	0.2905 (3)	0.8842 (3)	0.95580 (14)	0.0235 (4)
H8A	0.3349	0.9266	1.0059	0.035*
H8B	0.2472	0.7712	0.988	0.035*
H8C	0.1723	1.0068	0.9237	0.035*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cr1	0.01584 (17)	0.01495 (17)	0.01543 (18)	−0.00518 (12)	−0.00099 (12)	−0.00184 (11)
O1	0.0236 (7)	0.0172 (6)	0.0221 (7)	−0.0082 (5)	−0.0042 (6)	−0.0003 (5)
O2	0.0184 (6)	0.0184 (6)	0.0191 (7)	−0.0061 (5)	−0.0045 (5)	0.0017 (5)
O1C	0.0184 (7)	0.0246 (7)	0.0405 (9)	−0.0037 (6)	−0.0096 (6)	−0.0085 (6)
O3C	0.0481 (9)	0.0220 (7)	0.0257 (8)	−0.0089 (7)	−0.0069 (7)	−0.0080 (6)
O2C	0.0429 (9)	0.0283 (8)	0.0347 (9)	−0.0147 (7)	0.0155 (8)	−0.0002 (7)
C7	0.0196 (9)	0.0157 (9)	0.0176 (9)	−0.0056 (7)	−0.0026 (8)	−0.0001 (7)
C9	0.0208 (9)	0.0233 (10)	0.0234 (10)	−0.0097 (8)	−0.0048 (8)	−0.0030 (8)
C5	0.0156 (8)	0.0211 (9)	0.0259 (11)	−0.0088 (7)	0.0025 (8)	−0.0040 (8)
C1	0.0132 (8)	0.0191 (9)	0.0161 (9)	−0.0028 (7)	0.0013 (7)	−0.0033 (7)
C2	0.0164 (8)	0.0148 (8)	0.0200 (10)	−0.0021 (7)	−0.0001 (7)	−0.0029 (7)
C3O	0.0249 (10)	0.0231 (10)	0.0173 (10)	−0.0090 (8)	−0.0048 (8)	0.0012 (8)
C10	0.0231 (9)	0.0238 (10)	0.0236 (10)	−0.0116 (8)	−0.0018 (8)	−0.0025 (8)
C3	0.0171 (9)	0.0219 (9)	0.0188 (10)	−0.0019 (8)	−0.0047 (8)	−0.0016 (7)
C6	0.0156 (8)	0.0203 (9)	0.0161 (9)	−0.0063 (7)	0.0016 (7)	−0.0001 (7)
C1O	0.0222 (10)	0.0194 (9)	0.0209 (10)	−0.0107 (8)	0.0038 (8)	−0.0073 (7)
C4	0.0150 (8)	0.0278 (10)	0.0252 (10)	−0.0067 (8)	−0.0037 (8)	−0.0075 (8)
C2O	0.0252 (10)	0.0170 (9)	0.0274 (12)	−0.0040 (8)	−0.0005 (9)	−0.0036 (8)
C8	0.0241 (9)	0.0220 (10)	0.0188 (10)	−0.0053 (8)	−0.0013 (8)	−0.0038 (7)

Geometric parameters (Å, º) top

Cr1—C1O	1.837 (2)	C9—H9A	0.99
Cr1—C3O	1.846 (2)	C9—H9B	0.99
Cr1—C2O	1.854 (2)	C5—C6	1.401 (3)
Cr1—C5	2.1942 (18)	C5—C4	1.415 (3)
Cr1—C6	2.2062 (19)	C5—H5	0.95
Cr1—C4	2.2197 (18)	C1—C2	1.402 (3)
Cr1—C3	2.2248 (18)	C1—C6	1.422 (3)
Cr1—C2	2.2355 (18)	C2—C3	1.417 (3)
Cr1—C1	2.2440 (18)	C2—H2	0.95
O1—C7	1.416 (2)	C10—H10A	0.99
O1—C10	1.437 (2)	C10—H10B	0.99
O2—C7	1.430 (2)	C3—C4	1.403 (3)
O2—C9	1.434 (2)	C3—H3	0.95
O1C—C1O	1.156 (2)	C6—H6	0.95
O3C—C3O	1.150 (2)	C4—H4	0.95
O2C—C2O	1.155 (3)	C8—H8A	0.98
C7—C8	1.519 (3)	C8—H8B	0.98
C7—C1	1.530 (3)	C8—H8C	0.98
C9—C10	1.520 (3)

C1O—Cr1—C3O	85.12 (8)	C6—C5—Cr1	71.91 (10)
C1O—Cr1—C2O	90.23 (9)	C4—C5—Cr1	72.29 (11)
C3O—Cr1—C2O	88.90 (9)	C6—C5—H5	119.9
C1O—Cr1—C5	115.71 (8)	C4—C5—H5	119.9
C3O—Cr1—C5	88.65 (8)	Cr1—C5—H5	128.1
C2O—Cr1—C5	153.62 (8)	C2—C1—C6	119.20 (17)
C1O—Cr1—C6	91.04 (8)	C2—C1—C7	121.36 (16)
C3O—Cr1—C6	114.92 (8)	C6—C1—C7	119.23 (16)
C2O—Cr1—C6	156.17 (8)	C2—C1—Cr1	71.43 (10)
C5—Cr1—C6	37.12 (7)	C6—C1—Cr1	69.92 (10)
C1O—Cr1—C4	152.90 (8)	C7—C1—Cr1	135.38 (12)
C3O—Cr1—C4	90.08 (8)	C1—C2—C3	120.40 (17)
C2O—Cr1—C4	116.37 (8)	C1—C2—Cr1	72.09 (10)
C5—Cr1—C4	37.38 (7)	C3—C2—Cr1	71.06 (10)
C6—Cr1—C4	66.92 (7)	C1—C2—H2	119.8
C1O—Cr1—C3	157.39 (8)	C3—C2—H2	119.8
C3O—Cr1—C3	117.47 (8)	Cr1—C2—H2	129.5
C2O—Cr1—C3	91.19 (8)	O3C—C3O—Cr1	177.08 (17)
C5—Cr1—C3	66.90 (7)	O1—C10—C9	101.71 (15)
C6—Cr1—C3	78.82 (7)	O1—C10—H10A	111.4
C4—Cr1—C3	36.80 (7)	C9—C10—H10A	111.4
C1O—Cr1—C2	120.35 (8)	O1—C10—H10B	111.4
C3O—Cr1—C2	154.47 (8)	C9—C10—H10B	111.4
C2O—Cr1—C2	92.49 (8)	H10A—C10—H10B	109.3
C5—Cr1—C2	78.90 (7)	C4—C3—C2	120.15 (17)
C6—Cr1—C2	66.52 (7)	C4—C3—Cr1	71.40 (10)
C4—Cr1—C2	66.54 (7)	C2—C3—Cr1	71.89 (10)
C3—Cr1—C2	37.05 (7)	C4—C3—H3	119.9
C1O—Cr1—C1	93.34 (7)	C2—C3—H3	119.9
C3O—Cr1—C1	152.18 (8)	Cr1—C3—H3	129.1
C2O—Cr1—C1	118.90 (8)	C5—C6—C1	120.38 (17)
C5—Cr1—C1	66.98 (7)	C5—C6—Cr1	70.98 (11)
C6—Cr1—C1	37.27 (7)	C1—C6—Cr1	72.81 (11)
C4—Cr1—C1	78.72 (7)	C5—C6—H6	119.8
C3—Cr1—C1	66.38 (7)	C1—C6—H6	119.8
C2—Cr1—C1	36.48 (7)	Cr1—C6—H6	128.7
C7—O1—C10	106.41 (13)	O1C—C1O—Cr1	176.41 (16)
C7—O2—C9	108.32 (13)	C3—C4—C5	119.66 (18)
O1—C7—O2	106.85 (14)	C3—C4—Cr1	71.80 (11)
O1—C7—C8	108.85 (15)	C5—C4—Cr1	70.34 (10)
O2—C7—C8	109.64 (15)	C3—C4—H4	120.2
O1—C7—C1	112.00 (15)	C5—C4—H4	120.2
O2—C7—C1	109.66 (14)	Cr1—C4—H4	130.2
C8—C7—C1	109.78 (15)	O2C—C2O—Cr1	178.51 (18)
O2—C9—C10	103.74 (14)	C7—C8—H8A	109.5
O2—C9—H9A	111	C7—C8—H8B	109.5
C10—C9—H9A	111	H8A—C8—H8B	109.5
O2—C9—H9B	111	C7—C8—H8C	109.5
C10—C9—H9B	111	H8A—C8—H8C	109.5
H9A—C9—H9B	109	H8B—C8—H8C	109.5
C6—C5—C4	120.18 (17)

Experimental details

Crystal data
Chemical formula	[Cr(C₁₀H₁₂O₂)(CO)₃]
M_r	300.23
Crystal system, space group	Triclinic, P1
Temperature (K)	173
a, b, c (Å)	7.1950 (3), 7.2120 (3), 13.9235 (6)
α, β, γ (°)	75.573 (2), 79.277 (2), 62.734 (1)
V (Å³)	619.79 (5)
Z	2
Radiation type	Cu Kα
µ (mm⁻¹)	7.74
Crystal size (mm)	0.11 × 0.08 × 0.08

Data collection
Diffractometer	Bruker Proteum
Absorption correction	Multi-scan (SADABS; Bruker, 2000)
T_min, T_max	0.489, 0.587
No. of measured, independent and observed [I > 2σ(I)] reflections	13788, 2163, 2066
R_int	0.028
(sin θ/λ)_max (Å⁻¹)	0.604

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.028, 0.072, 1.11
No. of reflections	2163
No. of parameters	172
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.34, −0.19

Computer programs: PROTEUM2 (Bruker, 2005), SAINT (Bruker, 1998), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), ORTEP-3 (Farrugia, 1997) and RASTER3D (Merritt & Bacon, 1997), WinGX (Farrugia, 1999).

Selected geometric parameters (Å, º) top

Cr1—C1O	1.837 (2)	Cr1—C3	2.2248 (18)
Cr1—C3O	1.846 (2)	Cr1—C2	2.2355 (18)
Cr1—C2O	1.854 (2)	Cr1—C1	2.2440 (18)
Cr1—C5	2.1942 (18)	O1C—C1O	1.156 (2)
Cr1—C6	2.2062 (19)	O3C—C3O	1.150 (2)
Cr1—C4	2.2197 (18)	O2C—C2O	1.155 (3)

C1O—Cr1—C3O	85.12 (8)	C3O—Cr1—C2O	88.90 (9)
C1O—Cr1—C2O	90.23 (9)

Acknowledgements

CBD acknowledges stipend support provided by the National Institute of Standards and Technology grant No. 70NANB4H1093 and the National Science Foundation grant No. CHE-0227475. Support of this research by the Cancer Center Support CORE grant No. P30 CA-21765 and the American Lebanese Syrian Associated Charities (ALSAC) is gratefully acknowledged on behalf of CRR. CBD is also thankful to Professor Duane Miller for his support while writing this paper. Tragically, Charles Ross died before the publication of this paper. His contribution to this work and several others including the doctoral dissertation of CBD is greatly appreciated.

References

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