Trimethyl­phosphine–tris­(penta­fluoro­phen­yl)borane

The title simple Lewis acid–base adduct, C₂₁H₉BF₁₅P or (H₃C)₃P–B(C₆F₅)₃, is essentially insoluble in most non-coordinating organic solvents. The P—B bond lies along a threefold rotation axis. It crystallizes in the trigonal space group R. Weak intra­molecular C—H...F contacts are present between the methyl­phosphine and the ortho-F atoms of the fluoro­aryl­borane, resulting in an eclipsed geometry in the reaction partners. The observed insolubility is likely to be due, in part, to an additional inter­molecular network of weak contacts involving the para-F atoms of the B—C₆F₅ groups and the P(CH₃)₃ group.

Key indicators

• Single-crystal X-ray study
• T = 173 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.039
• wR factor = 0.095
• Data-to-parameter ratio = 12.0

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT029_ALERT_3_B _diffrn_measured_fraction_theta_full Low .......       0.96

Alert level C
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT432_ALERT_2_C Short Inter X...Y Contact  F5     ..  C6      ..       2.96 Ang.
PLAT480_ALERT_4_C Long H...A H-Bond Reported H2     ..  F1      ..       2.56 Ang.
PLAT480_ALERT_4_C Long H...A H-Bond Reported H1     ..  F3      ..       2.65 Ang.
PLAT764_ALERT_4_C Overcomplete CIF Bond List Detected (Rep/Expd) .       1.12 Ratio

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

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

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Computing details

Data collection: COLLECT (Nonius, 1998); cell refinement: DENZO (Otwinowski & Minor, 1997); data reduction: SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SAPI91 (Fan, 1991); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPII (Johnson, 1976); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

trimethylphosphine–tris(pentafluorophenyl)borane

Crystal data

C21H9BF15P	Dx = 1.873 Mg m^−3
Mr = 588.06	Mo Kα radiation, λ = 0.71073 Å
Trigonal, R3	Cell parameters from 4319 reflections
Hall symbol: -R 3	θ = 4.0–27.6°
a = 12.141 (6) Å	µ = 0.28 mm^−1
c = 24.503 (16) Å	T = 173 K
V = 3128 (3) Å^3	Prism, colourless
Z = 6	0.20 × 0.12 × 0.12 mm
F(000) = 1740

Data collection

Bruker Nonius KappaCCD area-detector diffractometer	1493 independent reflections
Radiation source: fine-focus sealed tube	1060 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.045
ω and φ scans	θmax = 27.6°, θmin = 4.0°
Absorption correction: multi-scan (SORTAV; Blessing, 1997)	h = −15→14
Tmin = 0.947, Tmax = 0.968	k = −12→14
4319 measured reflections	l = −31→20

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)] = 0.039	Hydrogen site location: difference Fourier map
wR(F^2) = 0.095	Only H-atom coordinates refined
S = 1.03	w = 1/[σ^2(Fo^2) + (0.0407P)^2 + 2.0279P] where P = (Fo^2 + 2Fc^2)/3
1493 reflections	(Δ/σ)max < 0.001
124 parameters	Δρmax = 0.21 e Å^−3
0 restraints	Δρmin = −0.31 e Å^−3

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
P1	0.6667	0.3333	0.04522 (4)	0.0272 (3)
F1	0.44310 (11)	0.09899 (10)	−0.00518 (5)	0.0347 (3)
F2	0.20363 (11)	0.00674 (11)	−0.03763 (5)	0.0422 (4)
F3	0.14338 (11)	0.13811 (12)	−0.11142 (5)	0.0413 (4)
F4	0.33023 (11)	0.36652 (11)	−0.14935 (5)	0.0380 (3)
F5	0.56805 (10)	0.45948 (11)	−0.11876 (5)	0.0344 (3)
C1	0.8004 (2)	0.4717 (2)	0.07513 (9)	0.0351 (5)
H1	0.797 (2)	0.460 (2)	0.1139 (10)	0.042*
H2	0.795 (2)	0.543 (2)	0.0698 (9)	0.042*
H3	0.884 (2)	0.487 (2)	0.0611 (9)	0.042*
C2	0.51990 (17)	0.28682 (18)	−0.05783 (7)	0.0236 (4)
C3	0.41865 (19)	0.17162 (19)	−0.04023 (8)	0.0266 (5)
C4	0.29431 (18)	0.12015 (18)	−0.05671 (8)	0.0287 (5)
C5	0.26358 (18)	0.18613 (19)	−0.09361 (8)	0.0284 (5)
C6	0.35804 (18)	0.30086 (19)	−0.11266 (7)	0.0268 (5)
C7	0.48194 (18)	0.34818 (18)	−0.09516 (8)	0.0251 (4)
B1	0.6667	0.3333	−0.03888 (15)	0.0254 (9)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
P1	0.0333 (5)	0.025	0.0201 (5)	0.013	0.000	0.000
F1	0.0349 (7)	0.0312 (7)	0.0342 (7)	0.0137 (6)	−0.0020 (5)	0.0094 (5)
F2	0.0299 (7)	0.0364 (7)	0.0447 (8)	0.0049 (6)	0.0014 (6)	0.0088 (6)
F3	0.0253 (7)	0.0511 (8)	0.0435 (8)	0.0163 (6)	−0.0054 (5)	−0.0020 (6)
F4	0.0397 (7)	0.0449 (8)	0.0356 (7)	0.0259 (6)	−0.0061 (6)	0.0058 (5)
F5	0.0328 (7)	0.0327 (7)	0.0329 (7)	0.0128 (6)	−0.0009 (5)	0.0103 (5)
C1	0.0394 (14)	0.0390 (14)	0.0256 (12)	0.0185 (12)	−0.0044 (10)	−0.0056 (10)
C2	0.0269 (11)	0.0261 (11)	0.0200 (10)	0.0150 (9)	0.0005 (8)	−0.0019 (8)
C3	0.0299 (11)	0.0296 (11)	0.0202 (10)	0.0148 (9)	0.0004 (8)	0.0030 (8)
C4	0.0249 (11)	0.0266 (11)	0.0276 (11)	0.0075 (9)	0.0044 (9)	0.0013 (8)
C5	0.0211 (11)	0.0379 (12)	0.0262 (11)	0.0149 (10)	−0.0025 (8)	−0.0066 (9)
C6	0.0308 (11)	0.0346 (12)	0.0224 (10)	0.0220 (10)	−0.0014 (8)	−0.0011 (8)
C7	0.0270 (11)	0.0233 (10)	0.0233 (10)	0.0113 (9)	0.0052 (8)	0.0027 (8)
B1	0.031 (2)	0.023	0.0201 (19)	0.011	0.000	0.000

Geometric parameters (Å, º)

P1—C1^i	1.808 (2)	C1—H3	0.99 (2)
P1—C1	1.808 (2)	C2—C3	1.391 (3)
P1—C1^ii	1.808 (2)	C2—C7	1.395 (3)
P1—B1	2.061 (4)	C2—B1	1.644 (2)
F1—C3	1.366 (2)	C3—C4	1.375 (3)
F2—C4	1.346 (2)	C4—C5	1.377 (3)
F3—C5	1.345 (2)	C5—C6	1.370 (3)
F4—C6	1.352 (2)	C6—C7	1.383 (3)
F5—C7	1.357 (2)	B1—C2^ii	1.644 (2)
C1—H1	0.96 (2)	B1—C2^i	1.644 (2)
C1—H2	0.91 (2)
C1^i—P1—C1	104.68 (9)	F2—C4—C3	120.91 (18)
C1^i—P1—C1^ii	104.68 (9)	F2—C4—C5	120.15 (17)
C1—P1—C1^ii	104.68 (9)	C3—C4—C5	118.94 (18)
C1^i—P1—B1	113.92 (8)	F3—C5—C6	120.36 (18)
C1—P1—B1	113.92 (8)	F3—C5—C4	120.77 (18)
C1^ii—P1—B1	113.92 (8)	C6—C5—C4	118.86 (18)
P1—C1—H1	108.3 (13)	F4—C6—C5	119.83 (17)
P1—C1—H2	111.8 (14)	F4—C6—C7	120.12 (17)
H1—C1—H2	105 (2)	C5—C6—C7	120.04 (18)
P1—C1—H3	113.0 (12)	F5—C7—C6	114.71 (16)
H1—C1—H3	109.7 (18)	F5—C7—C2	121.02 (16)
H2—C1—H3	109 (2)	C6—C7—C2	124.22 (17)
C3—C2—C7	112.24 (16)	C2^ii—B1—C2^i	112.35 (12)
C3—C2—B1	121.26 (16)	C2^ii—B1—C2	112.35 (12)
C7—C2—B1	126.32 (17)	C2^i—B1—C2	112.35 (12)
F1—C3—C4	115.80 (17)	C2^ii—B1—P1	106.41 (14)
F1—C3—C2	118.45 (16)	C2^i—B1—P1	106.41 (14)
C4—C3—C2	125.70 (18)	C2—B1—P1	106.41 (14)
C7—C2—C3—F1	177.45 (16)	C3—C2—C7—F5	−177.25 (16)
B1—C2—C3—F1	2.1 (3)	B1—C2—C7—F5	−2.2 (3)
C7—C2—C3—C4	0.3 (3)	C3—C2—C7—C6	0.3 (3)
B1—C2—C3—C4	−175.1 (2)	B1—C2—C7—C6	175.38 (19)
F1—C3—C4—F2	1.8 (3)	C3—C2—B1—C2^ii	59.9 (3)
C2—C3—C4—F2	179.07 (18)	C7—C2—B1—C2^ii	−114.76 (16)
F1—C3—C4—C5	−177.67 (17)	C3—C2—B1—C2^i	−172.22 (16)
C2—C3—C4—C5	−0.4 (3)	C7—C2—B1—C2^i	13.1 (3)
F2—C4—C5—F3	−0.6 (3)	C3—C2—B1—P1	−56.15 (18)
C3—C4—C5—F3	178.94 (17)	C7—C2—B1—P1	129.17 (18)
F2—C4—C5—C6	−179.48 (17)	C1^i—P1—B1—C2^ii	−16.40 (11)
C3—C4—C5—C6	0.0 (3)	C1—P1—B1—C2^ii	103.60 (11)
F3—C5—C6—F4	0.3 (3)	C1^ii—P1—B1—C2^ii	−136.40 (11)
C4—C5—C6—F4	179.25 (17)	C1^i—P1—B1—C2^i	−136.40 (11)
F3—C5—C6—C7	−178.43 (17)	C1—P1—B1—C2^i	−16.40 (11)
C4—C5—C6—C7	0.5 (3)	C1^ii—P1—B1—C2^i	103.60 (11)
F4—C6—C7—F5	−1.8 (2)	C1^i—P1—B1—C2	103.60 (11)
C5—C6—C7—F5	177.00 (17)	C1—P1—B1—C2	−136.40 (11)
F4—C6—C7—C2	−179.43 (17)	C1^ii—P1—B1—C2	−16.40 (11)
C5—C6—C7—C2	−0.7 (3)

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

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C1—H3···F1^ii	0.99 (2)	2.46 (2)	3.107 (3)	122 (2)
C1—H2···F1^i	0.91 (2)	2.56 (2)	3.137 (3)	122 (2)
C1—H1···F3^iii	0.96 (2)	2.65 (2)	3.599 (3)	170 (2)

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