Di-tert-butyl­methyl­phospho­nium chloride

Geometric parameters of the title compound, C₉H₂₂P⁺·Cl⁻, are in the usual ranges. Cations and anions are connected by a P—H...Cl hydrogen bond.

Key indicators

• Single-crystal X-ray study
• T = 173 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.023
• wR factor = 0.060
• Data-to-parameter ratio = 20.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT850_ALERT_2_C Check Flack Parameter Exact Value 0.00 and su ..       0.07

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           25.62
           From the CIF: _reflns_number_total               2191
           Count of symmetry unique reflns         1294
           Completeness (_total/calc)            169.32%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured       897
           Fraction of Friedel pairs measured     0.693
           Are heavy atom types Z>Si present        yes

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   1 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
   1 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 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

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S1. Comment

Very recently, we have reported that treatment of Ph₂PCH₃ with nBuLi led to the formation of the lithium methanide Li⁺[CH₂PPh₂]^- (Ruth et al., 2007). Thereby Ph₂PCH₃ reacts as a Brønsted acid. Here we describe a Lewis-base reaction of tBu₂PCH₃ with NH₄Cl which produces the phosphonium chloride [tBu₂PHCH₃]⁺ Cl^-. X-ray quality crystals of the title compound have been obtained from a tetrahydrofuran solution at ambient temperature.

The title compound, C₉H₂₂P^+.Cl^-, is composed of di(t-butyl)-methylphosphonium cations and chloride anions. Geometric parameters are in the usual ranges. Cations and anions are connected by a P—H···Cl hydrogen bond.

Related literature

For related literature, see: Ruth et al. (2007).

S2. Experimental

At room temperature, 3.5 ml of a 1.0 M solution of NH₄Cl in water was added to a solution of 0.05 g (0.31 mmol) tBu₂PCH₃ in 3 ml pentane and 1 ml Et₂O. After removal of the solvent from the organic layer the residue was dissolved in 0.5 ml tetrahydrofuran. Colourless crystals of title compound were grown from this tetrahydrofuran solution at ambient temperature.

S3. Refinement

H atoms were found in a difference map but those bonded to C were refined with fixed individual displacement parameters [U_iso(H) = 1.5 U_eq(C)] using a riding model with C—H = 0.98 Å. The H atom bonded to P was isotropically refined.

Computing details

Data collection: X-AREA (Stoe & Cie, 2001); cell refinement: X-AREA (Stoe & Cie, 2001); data reduction: X-AREA (Stoe & Cie, 2001); program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: XP in SHELXTL-Plus (Sheldrick, 1991); software used to prepare material for publication: SHELXL97 (Sheldrick, 1997).

Figures

	Fig. 1. Perspective view of the title compound with the atom numbering scheme. Displacement ellipsoids are at the 50% probability level. The H bond is drawn as a dashed line.
	Fig. 2. The formation of the title compound.

Di-tert-butylmethylphosphonium chloride

Crystal data

C9H22P^+·Cl^−	F(000) = 432
Mr = 196.69	Dx = 1.118 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 14606 reflections
a = 7.0601 (6) Å	θ = 3.5–25.8°
b = 10.5406 (6) Å	µ = 0.41 mm^−1
c = 15.7074 (10) Å	T = 173 K
V = 1168.91 (14) Å^3	Block, colourless
Z = 4	0.42 × 0.37 × 0.35 mm

Data collection

Stoe IPDSII two-circle diffractometer	2191 independent reflections
Radiation source: fine-focus sealed tube	2138 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.065
ω scans	θmax = 25.6°, θmin = 3.5°
Absorption correction: multi-scan (MULABS; Spek, 2003; Blessing, 1995)	h = −8→8
Tmin = 0.846, Tmax = 0.869	k = −12→12
16039 measured reflections	l = −19→18

Refinement

Refinement on F^2	Hydrogen site location: inferred from neighbouring sites
Least-squares matrix: full	H atoms treated by a mixture of independent and constrained refinement
R[F^2 > 2σ(F^2)] = 0.023	w = 1/[σ^2(Fo^2) + (0.0316P)^2 + 0.2388P] where P = (Fo^2 + 2Fc^2)/3
wR(F^2) = 0.060	(Δ/σ)max = 0.001
S = 1.08	Δρmax = 0.22 e Å^−3
2191 reflections	Δρmin = −0.21 e Å^−3
105 parameters	Extinction correction: SHELXL97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
0 restraints	Extinction coefficient: 0.021 (2)
Primary atom site location: structure-invariant direct methods	Absolute structure: Flack (1983), 905 Friedel pairs
Secondary atom site location: difference Fourier map	Absolute structure parameter: 0.00 (7)

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
Cl1	0.22208 (5)	0.43238 (4)	0.79852 (3)	0.02524 (12)
P1	0.64522 (5)	0.49139 (4)	0.65011 (2)	0.01714 (11)
H1	0.512 (3)	0.5180 (18)	0.7049 (13)	0.029 (5)*
C1	0.7006 (2)	0.32277 (14)	0.67016 (10)	0.0190 (3)
C2	0.8916 (2)	0.28544 (16)	0.62979 (11)	0.0255 (4)
H2A	0.8829	0.2931	0.5677	0.038*
H2B	0.9221	0.1976	0.6449	0.038*
H2C	0.9913	0.3419	0.6510	0.038*
C3	0.7165 (3)	0.30947 (16)	0.76817 (10)	0.0253 (3)
H3A	0.5953	0.3324	0.7945	0.038*
H3B	0.8160	0.3661	0.7893	0.038*
H3C	0.7481	0.2216	0.7827	0.038*
C4	0.5391 (2)	0.23663 (16)	0.63818 (12)	0.0271 (4)
H4A	0.4198	0.2622	0.6650	0.041*
H4B	0.5671	0.1483	0.6529	0.041*
H4C	0.5277	0.2447	0.5762	0.041*
C5	0.5531 (2)	0.53377 (15)	0.54320 (10)	0.0206 (3)
C6	0.6720 (2)	0.47265 (17)	0.47158 (10)	0.0284 (4)
H6A	0.8045	0.4990	0.4773	0.043*
H6B	0.6233	0.5001	0.4161	0.043*
H6C	0.6637	0.3801	0.4758	0.043*
C7	0.5622 (3)	0.67927 (16)	0.53430 (12)	0.0311 (4)
H7A	0.4854	0.7186	0.5791	0.047*
H7B	0.5130	0.7042	0.4784	0.047*
H7C	0.6939	0.7075	0.5397	0.047*
C8	0.3434 (2)	0.49260 (18)	0.53649 (11)	0.0291 (4)
H8A	0.2706	0.5320	0.5826	0.044*
H8B	0.3348	0.4001	0.5412	0.044*
H8C	0.2919	0.5197	0.4815	0.044*
C9	0.8495 (3)	0.58718 (16)	0.67419 (12)	0.0303 (4)
H9A	0.8202	0.6766	0.6633	0.045*
H9B	0.9558	0.5609	0.6382	0.045*
H9C	0.8838	0.5762	0.7342	0.045*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.02263 (18)	0.02150 (19)	0.0316 (2)	−0.00030 (15)	0.00044 (16)	−0.00198 (15)
P1	0.01824 (18)	0.01498 (19)	0.01820 (19)	0.00116 (15)	0.00001 (14)	−0.00105 (14)
C1	0.0221 (8)	0.0142 (7)	0.0206 (7)	0.0002 (6)	−0.0004 (6)	0.0001 (5)
C2	0.0263 (9)	0.0228 (8)	0.0274 (9)	0.0063 (7)	0.0021 (7)	−0.0004 (7)
C3	0.0281 (8)	0.0262 (8)	0.0216 (8)	0.0025 (7)	0.0002 (7)	0.0035 (6)
C4	0.0302 (9)	0.0197 (8)	0.0313 (9)	−0.0054 (7)	−0.0058 (8)	0.0021 (7)
C5	0.0223 (7)	0.0205 (8)	0.0191 (8)	0.0006 (6)	−0.0002 (6)	0.0030 (6)
C6	0.0317 (9)	0.0345 (10)	0.0191 (7)	0.0036 (7)	0.0038 (6)	0.0013 (6)
C7	0.0363 (9)	0.0221 (9)	0.0348 (10)	0.0022 (7)	−0.0027 (8)	0.0062 (7)
C8	0.0229 (7)	0.0353 (9)	0.0290 (8)	−0.0007 (8)	−0.0048 (6)	0.0020 (8)
C9	0.0297 (8)	0.0198 (8)	0.0413 (10)	−0.0039 (7)	−0.0114 (8)	0.0002 (7)

Geometric parameters (Å, º)

P1—C9	1.8009 (17)	C5—C7	1.541 (2)
P1—C1	1.8470 (15)	C5—C6	1.544 (2)
P1—C5	1.8554 (16)	C5—C8	1.546 (2)
P1—H1	1.308 (19)	C6—H6A	0.9800
C1—C2	1.541 (2)	C6—H6B	0.9800
C1—C4	1.542 (2)	C6—H6C	0.9800
C1—C3	1.550 (2)	C7—H7A	0.9800
C2—H2A	0.9800	C7—H7B	0.9800
C2—H2B	0.9800	C7—H7C	0.9800
C2—H2C	0.9800	C8—H8A	0.9800
C3—H3A	0.9800	C8—H8B	0.9800
C3—H3B	0.9800	C8—H8C	0.9800
C3—H3C	0.9800	C9—H9A	0.9800
C4—H4A	0.9800	C9—H9B	0.9800
C4—H4B	0.9800	C9—H9C	0.9800
C4—H4C	0.9800
C9—P1—C1	109.51 (8)	C7—C5—C6	109.05 (14)
C9—P1—C5	109.63 (8)	C7—C5—C8	108.23 (14)
C1—P1—C5	117.40 (7)	C6—C5—C8	110.71 (14)
C9—P1—H1	108.6 (8)	C7—C5—P1	107.88 (11)
C1—P1—H1	104.3 (9)	C6—C5—P1	111.61 (11)
C5—P1—H1	106.9 (8)	C8—C5—P1	109.25 (11)
C2—C1—C4	111.26 (13)	C5—C6—H6A	109.5
C2—C1—C3	108.81 (14)	C5—C6—H6B	109.5
C4—C1—C3	108.89 (13)	H6A—C6—H6B	109.5
C2—C1—P1	111.15 (11)	C5—C6—H6C	109.5
C4—C1—P1	110.76 (11)	H6A—C6—H6C	109.5
C3—C1—P1	105.77 (10)	H6B—C6—H6C	109.5
C1—C2—H2A	109.5	C5—C7—H7A	109.5
C1—C2—H2B	109.5	C5—C7—H7B	109.5
H2A—C2—H2B	109.5	H7A—C7—H7B	109.5
C1—C2—H2C	109.5	C5—C7—H7C	109.5
H2A—C2—H2C	109.5	H7A—C7—H7C	109.5
H2B—C2—H2C	109.5	H7B—C7—H7C	109.5
C1—C3—H3A	109.5	C5—C8—H8A	109.5
C1—C3—H3B	109.5	C5—C8—H8B	109.5
H3A—C3—H3B	109.5	H8A—C8—H8B	109.5
C1—C3—H3C	109.5	C5—C8—H8C	109.5
H3A—C3—H3C	109.5	H8A—C8—H8C	109.5
H3B—C3—H3C	109.5	H8B—C8—H8C	109.5
C1—C4—H4A	109.5	P1—C9—H9A	109.5
C1—C4—H4B	109.5	P1—C9—H9B	109.5
H4A—C4—H4B	109.5	H9A—C9—H9B	109.5
C1—C4—H4C	109.5	P1—C9—H9C	109.5
H4A—C4—H4C	109.5	H9A—C9—H9C	109.5
H4B—C4—H4C	109.5	H9B—C9—H9C	109.5
C9—P1—C1—C2	−47.69 (14)	C9—P1—C5—C7	−41.13 (14)
C5—P1—C1—C2	78.12 (13)	C1—P1—C5—C7	−166.88 (11)
C9—P1—C1—C4	−171.92 (12)	C9—P1—C5—C6	78.65 (13)
C5—P1—C1—C4	−46.11 (14)	C1—P1—C5—C6	−47.10 (14)
C9—P1—C1—C3	70.25 (13)	C9—P1—C5—C8	−158.57 (12)
C5—P1—C1—C3	−163.93 (10)	C1—P1—C5—C8	75.67 (13)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
P1—H1···Cl1	1.308 (19)	2.675 (19)	3.8400 (6)	147.2 (12)