Tri-p-tolyl­phosphine

Abstract

In the title compound C₂₁H₂₁P, the P atom is situated on a crystallographic threefold rotatory-inversion axis, resulting in threefold rotation symmetry of the title compound. The dihedral angles between the symmetry-related benzene rings are 87.40 (18)°.

Related literature

For related literature, see: Brown et al. (1988 ▶).

Experimental

Crystal data

• C₂₁H₂₁P

• M _r = 304.35

• Trigonal,

• a = 12.6562 (18) Å

• c = 19.696 (4) Å

• V = 2732.2 (8) ų

• Z = 6

• Mo Kα radiation

• μ = 0.15 mm⁻¹

• T = 293 (2) K

• 0.40 × 0.30 × 0.20 mm

Data collection

• Enraf–Nonius CAD-4 diffractometer

• Absorption correction: ψ scan (North et al., 1968 ▶) T _min = 0.958, T _max = 0.971

• 3464 measured reflections

• 1095 independent reflections

• 790 reflections with I > 2σ(I)

• R _int = 0.050

• 3 standard reflections every 200 reflections intensity decay: none

Refinement

• R[F ² > 2σ(F ²)] = 0.063

• wR(F ²) = 0.171

• S = 1.03

• 1095 reflections

• 67 parameters

• H-atom parameters constrained

• Δρ_max = 0.26 e Å⁻³

• Δρ_min = −0.34 e Å⁻³

Data collection: CAD-4 Software (Enraf–Nonius, 1989 ▶); cell refinement: CAD-4 Software; data reduction: XCAD4 (Harms & Wocadlo, 1995 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXL97.

Supplementary Material

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

supplementary crystallographic information

Comment

Some organophosphorus derivatives are important chemical materials, which are primarily used as intermediates of organic phosphorus flame retardants and phosphorus ligands in biphasic water soluble catalysts. The P atom is situated on a crystallographic threefold rotatory-inversion axis, resulting in threefold rotation symmetry of the title compound.

The dihedral angles between the symmetry-related benzene rings are 87.40 (18)°.

Experimental

20 g Sodium (0.870 mol) was added to 125 ml toluene, then the mixture was heated up to 383 K and stirred to form fine particles of sodium, which subsequently melted. Then the temperature was lowered to 323 K. P-chlorotoluene (55.2 g / 0.436 mol) and phosphorus trichloride (19.8 g / 0.144 mol) were added, keeping the temperature between 323 K and 333 K for two hours. The product was concentrated in a vacuum to gain a white solid (35.0 g, 80%) (Brown et al., 1988). The pure title compound was obtained by crystallizing from methanol. Crystals suitable for X-ray diffraction were obtained by slow evaporation of an methanol solution.

Refinement

All H atoms bonded to the C atoms were placed geometrically at the distances of 0.93–0.97 Å, and included in the refinement in riding motion approximation with U_iso(H) = 1.2 or 1.5 U_eq of the carrier atom.

Figures

Fig. 1.

The molecular structure of the title compound, showing the atom-numbering scheme and displacement ellipsoids at the 30% probability level. Symmetry codes: (i) 1 - x + y,1 - x,z (ii) 1 - y + 1,x-y,z

Crystal data

C21H21P	Z = 6
Mr = 304.35	F000 = 972
Trigonal, R3	Dx = 1.110 Mg m−3
Hall symbol: -R 3	Mo Kα radiation λ = 0.71073 Å
a = 12.6562 (18) Å	Cell parameters from 25 reflections
b = 12.6562 (18) Å	θ = 10–13º
c = 19.696 (4) Å	µ = 0.15 mm−1
α = 90º	T = 293 (2) K
β = 90º	Block, colourless
γ = 120º	0.40 × 0.30 × 0.20 mm
V = 2732.2 (8) Å3

Data collection

Enraf–Nonius CAD-4 diffractometer	Rint = 0.050
Radiation source: fine-focus sealed tube	θmax = 25.2º
Monochromator: graphite	θmin = 2.1º
T = 293(2) K	h = −15→7
ω/2θ scans	k = 0→15
Absorption correction: ψ scan(North et al., 1968)	l = 0→23
Tmin = 0.958, Tmax = 0.971	3 standard reflections
3464 measured reflections	every 200 reflections
1095 independent reflections	intensity decay: none
790 reflections with I > 2σ(I)

Refinement

Refinement on F2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.063	H-atom parameters constrained
wR(F2) = 0.171	w = 1/[σ2(Fo2) + (0.05P)2 + 4P] where P = (Fo2 + 2Fc2)/3
S = 1.03	(Δ/σ)max < 0.001
1095 reflections	Δρmax = 0.26 e Å−3
67 parameters	Δρmin = −0.34 e Å−3
Primary atom site location: structure-invariant direct methods	Extinction correction: none

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
P	0.6667	0.3333	0.01046 (7)	0.0705 (5)
C1	0.8153 (4)	0.8316 (3)	−0.1198 (2)	0.0992 (12)
H1A	0.7776	0.8686	−0.0944	0.149*
H1B	0.7882	0.8209	−0.1661	0.149*
H1C	0.9024	0.8832	−0.1182	0.149*
C2	0.7805 (3)	0.7091 (3)	−0.08924 (18)	0.0710 (8)
C3	0.8232 (3)	0.6365 (3)	−0.11520 (14)	0.0647 (8)
H3A	0.8752	0.6636	−0.1525	0.078*
C4	0.7903 (3)	0.5238 (3)	−0.08689 (15)	0.0644 (7)
H4A	0.8205	0.4768	−0.1058	0.077*
C5	0.7147 (3)	0.4803 (2)	−0.03192 (14)	0.0609 (7)
C6	0.6732 (3)	0.5549 (3)	−0.0040 (2)	0.0811 (10)
H6A	0.6247	0.5301	0.0348	0.097*
C7	0.7050 (3)	0.6663 (3)	−0.03445 (19)	0.0809 (10)
H7A	0.6735	0.7130	−0.0167	0.097*

Atomic displacement parameters (Ų)

	U11	U22	U33	U12	U13	U23
P	0.0791 (6)	0.0791 (6)	0.0533 (8)	0.0396 (3)	0.000	0.000
C1	0.096 (3)	0.076 (2)	0.128 (4)	0.044 (2)	0.000 (2)	0.008 (2)
C2	0.0533 (16)	0.0599 (17)	0.097 (2)	0.0259 (14)	−0.0093 (15)	−0.0109 (16)
C3	0.0609 (16)	0.0699 (18)	0.0587 (17)	0.0294 (14)	0.0003 (13)	−0.0060 (13)
C4	0.0648 (17)	0.0653 (17)	0.0666 (18)	0.0353 (14)	−0.0009 (14)	−0.0129 (14)
C5	0.0607 (16)	0.0677 (17)	0.0530 (16)	0.0312 (13)	−0.0028 (12)	−0.0109 (13)
C6	0.069 (2)	0.083 (2)	0.091 (2)	0.0377 (17)	0.0151 (17)	−0.0131 (18)
C7	0.074 (2)	0.076 (2)	0.100 (3)	0.0436 (17)	0.0036 (18)	−0.0164 (18)

Geometric parameters (Å, °)

P—C5i	1.843 (3)	C3—C4	1.388 (4)
P—C5ii	1.843 (3)	C3—H3A	0.9300
P—C5	1.843 (3)	C4—C5	1.366 (4)
C1—C2	1.508 (4)	C4—H4A	0.9300
C1—H1A	0.9600	C5—C6	1.401 (4)
C1—H1B	0.9600	C6—C7	1.394 (5)
C1—H1C	0.9600	C6—H6A	0.9300
C2—C7	1.361 (5)	C7—H7A	0.9300
C2—C3	1.377 (4)
C5i—P—C5ii	101.08 (11)	C4—C3—H3A	119.3
C5i—P—C5	101.08 (11)	C5—C4—C3	121.5 (3)
C5ii—P—C5	101.08 (11)	C5—C4—H4A	119.3
C2—C1—H1A	109.5	C3—C4—H4A	119.3
C2—C1—H1B	109.5	C4—C5—C6	117.6 (3)
H1A—C1—H1B	109.5	C4—C5—P	125.2 (2)
C2—C1—H1C	109.5	C6—C5—P	117.1 (2)
H1A—C1—H1C	109.5	C7—C6—C5	119.8 (3)
H1B—C1—H1C	109.5	C7—C6—H6A	120.1
C7—C2—C3	117.4 (3)	C5—C6—H6A	120.1
C7—C2—C1	120.8 (3)	C2—C7—C6	122.3 (3)
C3—C2—C1	121.8 (3)	C2—C7—H7A	118.8
C2—C3—C4	121.4 (3)	C6—C7—H7A	118.8
C2—C3—H3A	119.3
C7—C2—C3—C4	0.3 (5)	C5i—P—C5—C6	−169.0 (2)
C1—C2—C3—C4	−179.8 (3)	C5ii—P—C5—C6	87.2 (3)
C2—C3—C4—C5	−0.3 (5)	C4—C5—C6—C7	3.0 (5)
C3—C4—C5—C6	−1.4 (5)	P—C5—C6—C7	−179.0 (3)
C3—C4—C5—P	−179.2 (2)	C3—C2—C7—C6	1.5 (5)
C5i—P—C5—C4	8.8 (3)	C1—C2—C7—C6	−178.4 (3)
C5ii—P—C5—C4	−95.0 (2)	C5—C6—C7—C2	−3.2 (5)

Symmetry codes: (i) −x+y+1, −x+1, z; (ii) −y+1, x−y, z.