Henicosane-1,21-dithiol

In the title compound, C₂₁H₄₄S₂, the molecular skeleton including both terminal S atoms has an all-trans conformation. The mol­ecules form layers with a thickness of c/2 and the long axis of the mol­ecule is inclined to the ab plane in the crystal structure. This molecular arrangement is similar to that of the smectic C structure of liquid crystals.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.056
• wR factor = 0.123
• Data-to-parameter ratio = 16.3

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT026_ALERT_3_C Ratio Observed / Unique Reflections too Low ....         46 Perc.
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.96
PLAT063_ALERT_3_C Crystal Probably too Large for Beam Size .......       0.65 mm
PLAT250_ALERT_2_C Large U3/U1 Ratio for Average U(i,j) Tensor ....       2.32
PLAT322_ALERT_2_C Check Hybridisation of  S2     in Main Residue .          ?
PLAT420_ALERT_2_C D-H Without Acceptor       S1     -   H1S    ...          ?
PLAT420_ALERT_2_C D-H Without Acceptor       S2     -   H2S    ...          ?

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

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   4 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
   0 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: MSC/AFC Diffractometer Control Software (Molecular Structure Corporation, 1992); cell refinement: MSC/AFC Diffractometer Control Software; data reduction: CrystalStructure (Molecular Structure Corporation & Rigaku, 2001); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: CRYSTALS (Watkin et al., 1996); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997); software used to prepare material for publication: CrystalStructure.

Henicosane-1,21-dithiol

Crystal data

C21H44S2	Z = 2
Mr = 360.70	F(000) = 404.00
Triclinic, P1	Dx = 1.044 Mg m^−3
Hall symbol: -P 1	Cu Kα radiation, λ = 1.5418 Å
a = 4.7477 (5) Å	Cell parameters from 25 reflections
b = 5.5680 (11) Å	θ = 10.0–18.8°
c = 44.455 (5) Å	µ = 2.07 mm^−1
α = 87.619 (13)°	T = 296 K
β = 87.920 (9)°	Plate, colourless
γ = 77.733 (11)°	0.65 × 0.22 × 0.01 mm
V = 1146.9 (3) Å^3

Data collection

Rigaku AFC-5R diffractometer	Rint = 0.019
ω scans	θmax = 70.1°
Absorption correction: ψ scan (North et al., 1968)	h = −5→5
Tmin = 0.640, Tmax = 0.977	k = −1→6
5611 measured reflections	l = −54→54
4187 independent reflections	3 standard reflections every 150 reflections
1926 reflections with F^2 > 2σ(F^2)	intensity decay: 12.4%

Refinement

Refinement on F^2	w = (4Fo^2)/[0.0001Fo^2 + 3.3σ^2(Fo) + 0.55]
R[F^2 > 2σ(F^2)] = 0.056	(Δ/σ)max < 0.001
wR(F^2) = 0.123	Δρmax = 0.60 e Å^−3
S = 1.00	Δρmin = −0.48 e Å^−3
4187 reflections	Extinction correction: Larson (1970)
257 parameters	Extinction coefficient: 23.4 (1)
H-atom parameters constrained

Special details

Refinement. Refinement using reflections with F² > -10.0 σ(F²). The weighted R-factor (wR) and goodness of fit (S) are based on F². R-factor (gt) are based on F. The threshold expression of F² > 2.0 σ(F²) is used only for calculating R-factor (gt).

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

	x	y	z	Uiso*/Ueq
S1	1.3600 (3)	−0.7742 (2)	0.52661 (3)	0.0952 (5)
S2	0.3417 (3)	2.8117 (2)	0.97663 (3)	0.0993 (5)
C1	1.1122 (8)	−0.5364 (6)	0.54564 (7)	0.0751 (13)
C2	1.2436 (7)	−0.4111 (6)	0.56909 (7)	0.0570 (11)
C3	1.0232 (7)	−0.2212 (6)	0.58586 (7)	0.0565 (11)
C4	1.1522 (7)	−0.0899 (6)	0.60936 (7)	0.0528 (11)
C5	0.9320 (7)	0.0949 (5)	0.62651 (7)	0.0527 (11)
C6	1.0587 (7)	0.2278 (5)	0.64994 (7)	0.0511 (11)
C7	0.8380 (7)	0.4129 (5)	0.66726 (6)	0.0500 (11)
C8	0.9642 (7)	0.5470 (5)	0.69058 (7)	0.0498 (11)
C9	0.7431 (7)	0.7302 (5)	0.70789 (7)	0.0505 (11)
C10	0.8693 (6)	0.8660 (5)	0.73108 (6)	0.0496 (11)
C11	0.6480 (7)	1.0485 (5)	0.74846 (7)	0.0502 (10)
C12	0.7735 (7)	1.1849 (5)	0.77161 (6)	0.0504 (11)
C13	0.5528 (7)	1.3678 (5)	0.78911 (6)	0.0507 (11)
C14	0.6801 (7)	1.5034 (5)	0.81227 (7)	0.0503 (11)
C15	0.4586 (7)	1.6854 (5)	0.82977 (6)	0.0512 (11)
C16	0.5859 (7)	1.8220 (6)	0.85282 (7)	0.0514 (11)
C17	0.3640 (7)	2.0029 (6)	0.87054 (7)	0.0534 (11)
C18	0.4937 (7)	2.1386 (6)	0.89347 (7)	0.0555 (11)
C19	0.2728 (7)	2.3168 (6)	0.91171 (7)	0.0587 (12)
C20	0.4060 (7)	2.4573 (6)	0.93380 (7)	0.0594 (12)
C21	0.1831 (8)	2.6256 (7)	0.95274 (8)	0.0789 (14)
H1	1.0304	−0.4153	0.53095	0.089*
H2	0.9645	−0.6064	0.55511	0.089*
H3	1.3832	−0.3318	0.55954	0.068*
H4	1.3351	−0.5326	0.58325	0.068*
H5	0.8855	−0.3015	0.59561	0.067*
H6	0.9297	−0.1016	0.57159	0.067*
H7	1.2865	−0.0063	0.59956	0.063*
H8	1.2496	−0.2098	0.62337	0.063*
H9	0.7982	0.0109	0.63636	0.063*
H10	0.8340	0.2141	0.61246	0.063*
H11	1.1572	0.1085	0.66395	0.061*
H12	1.1921	0.3121	0.64007	0.061*
H13	0.7388	0.5316	0.65324	0.060*
H14	0.7054	0.3284	0.67722	0.060*
H15	1.0951	0.6335	0.68067	0.060*
H16	1.0652	0.4282	0.70449	0.060*
H17	0.6139	0.6434	0.71808	0.061*
H18	0.6400	0.8476	0.69396	0.061*
H19	0.9996	0.9523	0.72098	0.060*
H20	0.9711	0.7482	0.74504	0.060*
H21	0.5460	1.1661	0.73449	0.060*
H22	0.5178	0.9621	0.75856	0.060*
H23	0.8755	1.0671	0.78556	0.061*
H24	0.9036	1.2712	0.76149	0.061*
H25	0.4225	1.2818	0.79923	0.061*
H26	0.4508	1.4860	0.77519	0.061*
H27	0.8099	1.5900	0.80215	0.061*
H28	0.7826	1.3854	0.82617	0.061*
H29	0.3555	1.8029	0.81585	0.062*
H30	0.3294	1.5986	0.83996	0.062*
H31	0.6903	1.7044	0.86664	0.062*
H32	0.7139	1.9098	0.84260	0.062*
H33	0.2594	2.1207	0.85676	0.064*
H34	0.2360	1.9154	0.88082	0.064*
H35	0.6191	2.2282	0.88312	0.067*
H36	0.6012	2.0204	0.90701	0.067*
H37	0.1609	2.4322	0.89818	0.071*
H38	0.1511	2.2268	0.92261	0.071*
H39	0.5247	2.3422	0.94681	0.072*
H40	0.5206	2.5536	0.92287	0.072*
H41	0.0802	2.5280	0.96508	0.095*
H42	0.0534	2.7309	0.93972	0.095*
H1s	1.481 (8)	−0.702 (7)	0.5148 (8)	0.1113*
H2s	0.330 (8)	2.683 (6)	0.9951 (8)	0.1152*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.1200 (12)	0.0823 (9)	0.0780 (8)	−0.0045 (7)	0.0135 (7)	−0.0411 (7)
S2	0.1346 (12)	0.0883 (9)	0.0796 (8)	−0.0259 (8)	−0.0023 (8)	−0.0450 (7)
C1	0.081 (3)	0.075 (3)	0.067 (2)	−0.005 (2)	−0.005 (2)	−0.034 (2)
C2	0.064 (3)	0.052 (2)	0.053 (2)	−0.0070 (18)	−0.0002 (18)	−0.0179 (18)
C3	0.056 (2)	0.054 (2)	0.057 (2)	−0.0087 (18)	−0.0025 (18)	−0.0229 (18)
C4	0.054 (2)	0.051 (2)	0.054 (2)	−0.0070 (18)	−0.0017 (18)	−0.0204 (18)
C5	0.052 (2)	0.054 (2)	0.052 (2)	−0.0065 (18)	−0.0017 (17)	−0.0189 (18)
C6	0.053 (2)	0.048 (2)	0.052 (2)	−0.0064 (17)	−0.0024 (17)	−0.0191 (17)
C7	0.051 (2)	0.048 (2)	0.051 (2)	−0.0071 (17)	−0.0011 (17)	−0.0190 (17)
C8	0.052 (2)	0.048 (2)	0.050 (2)	−0.0073 (17)	−0.0004 (17)	−0.0197 (17)
C9	0.050 (2)	0.051 (2)	0.0496 (19)	−0.0063 (17)	−0.0005 (17)	−0.0174 (17)
C10	0.051 (2)	0.049 (2)	0.049 (2)	−0.0081 (18)	0.0002 (17)	−0.0202 (18)
C11	0.053 (2)	0.049 (2)	0.0482 (18)	−0.0080 (18)	−0.0014 (16)	−0.0182 (17)
C12	0.052 (2)	0.050 (2)	0.049 (2)	−0.0074 (18)	−0.0005 (18)	−0.0193 (18)
C13	0.052 (2)	0.051 (2)	0.049 (2)	−0.0064 (17)	−0.0017 (17)	−0.0191 (17)
C14	0.051 (2)	0.050 (2)	0.050 (2)	−0.0088 (17)	−0.0025 (17)	−0.0209 (17)
C15	0.053 (2)	0.051 (2)	0.0498 (19)	−0.0090 (17)	−0.0013 (17)	−0.0192 (17)
C16	0.053 (2)	0.052 (2)	0.049 (2)	−0.0076 (18)	−0.0016 (17)	−0.0192 (17)
C17	0.054 (2)	0.056 (2)	0.050 (2)	−0.0082 (18)	−0.0026 (17)	−0.0174 (18)
C18	0.057 (3)	0.058 (2)	0.052 (2)	−0.0083 (18)	−0.0028 (18)	−0.0227 (18)
C19	0.059 (2)	0.061 (2)	0.057 (2)	−0.0085 (19)	−0.0027 (18)	−0.0264 (19)
C20	0.063 (3)	0.062 (2)	0.055 (2)	−0.0131 (19)	0.0013 (19)	−0.0248 (19)
C21	0.078 (3)	0.087 (3)	0.073 (3)	−0.013 (2)	0.007 (2)	−0.042 (2)

Geometric parameters (Å, º)

S1—C1	1.792 (3)	C5—H10	0.95
S2—C21	1.803 (3)	C6—H11	0.95
C1—C2	1.502 (4)	C6—H12	0.95
C2—C3	1.519 (3)	C7—H13	0.95
C3—C4	1.517 (3)	C7—H14	0.95
C4—C5	1.511 (3)	C8—H15	0.95
C5—C6	1.514 (3)	C8—H16	0.95
C6—C7	1.517 (3)	C9—H17	0.95
C7—C8	1.513 (3)	C9—H18	0.95
C8—C9	1.512 (3)	C10—H19	0.95
C9—C10	1.515 (3)	C10—H20	0.95
C10—C11	1.512 (3)	C11—H21	0.95
C11—C12	1.515 (3)	C11—H22	0.95
C12—C13	1.514 (3)	C12—H23	0.95
C13—C14	1.516 (3)	C12—H24	0.95
C14—C15	1.514 (3)	C13—H25	0.95
C15—C16	1.516 (3)	C13—H26	0.95
C16—C17	1.517 (3)	C14—H27	0.95
C17—C18	1.515 (3)	C14—H28	0.95
C18—C19	1.518 (3)	C15—H29	0.95
C19—C20	1.515 (4)	C15—H30	0.95
C20—C21	1.512 (4)	C16—H31	0.95
S1—H1s	0.91 (4)	C16—H32	0.95
S2—H2s	1.08 (4)	C17—H33	0.95
C1—H1	0.95	C17—H34	0.95
C1—H2	0.95	C18—H35	0.95
C2—H3	0.95	C18—H36	0.95
C2—H4	0.95	C19—H37	0.95
C3—H5	0.95	C19—H38	0.95
C3—H6	0.95	C20—H39	0.95
C4—H7	0.95	C20—H40	0.95
C4—H8	0.95	C21—H41	0.95
C5—H9	0.95	C21—H42	0.95
S1···S1^i	3.5401 (18)	S2^ii···S2^iii	3.5919 (19)
S1—C1—C2	114.8 (2)	C8—C9—H18	108.5
C1—C2—C3	113.0 (3)	C10—C9—H18	108.5
C2—C3—C4	113.8 (3)	H17—C9—H18	109.4
C3—C4—C5	113.8 (3)	C9—C10—H19	108.3
C4—C5—C6	114.2 (3)	C11—C10—H19	108.3
C5—C6—C7	114.3 (2)	C9—C10—H20	108.2
C6—C7—C8	114.5 (2)	C11—C10—H20	108.2
C7—C8—C9	114.2 (3)	H19—C10—H20	109.5
C8—C9—C10	114.3 (2)	C10—C11—H21	108.2
C9—C10—C11	114.2 (2)	C12—C11—H21	108.1
C10—C11—C12	114.4 (3)	C10—C11—H22	108.3
C11—C12—C13	114.6 (2)	C12—C11—H22	108.3
C12—C13—C14	114.3 (2)	H21—C11—H22	109.5
C13—C14—C15	114.1 (2)	C11—C12—H23	108.1
C14—C15—C16	114.1 (2)	C13—C12—H23	108.1
C15—C16—C17	114.2 (3)	C11—C12—H24	108.2
C16—C17—C18	113.7 (3)	C13—C12—H24	108.2
C17—C18—C19	114.1 (3)	H23—C12—H24	109.5
C18—C19—C20	113.5 (3)	C12—C13—H25	108.3
C19—C20—C21	112.8 (3)	C14—C13—H25	108.3
S2—C21—C20	112.5 (2)	C12—C13—H26	108.2
C1—S1—H1s	108 (2)	C14—C13—H26	108.2
C21—S2—H2s	89.6 (19)	H25—C13—H26	109.5
S1—C1—H1	107.9	C13—C14—H27	108.4
C2—C1—H1	108.0	C15—C14—H27	108.4
S1—C1—H2	108.3	C13—C14—H28	108.2
C2—C1—H2	108.3	C15—C14—H28	108.2
H1—C1—H2	109.5	H27—C14—H28	109.5
C1—C2—H3	108.7	C14—C15—H29	108.2
C3—C2—H3	108.7	C16—C15—H29	108.3
C1—C2—H4	108.4	C14—C15—H30	108.3
C3—C2—H4	108.5	C16—C15—H30	108.4
H3—C2—H4	109.5	H29—C15—H30	109.5
C2—C3—H5	108.5	C15—C16—H31	108.2
C4—C3—H5	108.4	C17—C16—H31	108.2
C2—C3—H6	108.3	C15—C16—H32	108.4
C4—C3—H6	108.3	C17—C16—H32	108.3
H5—C3—H6	109.5	H31—C16—H32	109.5
C3—C4—H7	108.5	C16—C17—H33	108.3
C5—C4—H7	108.4	C18—C17—H33	108.3
C3—C4—H8	108.3	C16—C17—H34	108.5
C5—C4—H8	108.3	C18—C17—H34	108.5
H7—C4—H8	109.5	H33—C17—H34	109.5
C4—C5—H9	108.3	C17—C18—H35	108.4
C6—C5—H9	108.3	C19—C18—H35	108.4
C4—C5—H10	108.2	C17—C18—H36	108.2
C6—C5—H10	108.2	C19—C18—H36	108.2
H9—C5—H10	109.5	H35—C18—H36	109.5
C5—C6—H11	108.2	C18—C19—H37	108.4
C7—C6—H11	108.2	C20—C19—H37	108.3
C5—C6—H12	108.3	C18—C19—H38	108.5
C7—C6—H12	108.3	C20—C19—H38	108.6
H11—C6—H12	109.5	H37—C19—H38	109.4
C6—C7—H13	108.2	C19—C20—H39	108.5
C8—C7—H13	108.1	C21—C20—H39	108.6
C6—C7—H14	108.3	C19—C20—H40	108.8
C8—C7—H14	108.2	C21—C20—H40	108.7
H13—C7—H14	109.5	H39—C20—H40	109.5
C7—C8—H15	108.5	S2—C21—H41	108.6
C9—C8—H15	107.9	C20—C21—H41	108.7
C7—C8—H16	108.2	S2—C21—H42	108.8
C9—C8—H16	108.5	C20—C21—H42	108.7
H15—C8—H16	109.5	H41—C21—H42	109.5
C8—C9—H17	108.0	C1—S1—S1^i	160.19 (13)
C10—C9—H17	108.0	C21^ii—S2^ii—S2^iii	179.21 (14)
S1—C1—C2—C3	−176.7 (2)	C11—C12—C13—C14	179.9 (3)
C1—C2—C3—C4	−179.2 (3)	C12—C13—C14—C15	−179.8 (2)
C2—C3—C4—C5	−178.7 (3)	C13—C14—C15—C16	−179.7 (2)
C3—C4—C5—C6	−179.7 (3)	C14—C15—C16—C17	−179.5 (3)
C4—C5—C6—C7	−179.8 (3)	C15—C16—C17—C18	−179.9 (3)
C5—C6—C7—C8	−179.7 (3)	C16—C17—C18—C19	−179.0 (3)
C6—C7—C8—C9	−179.7 (3)	C17—C18—C19—C20	−178.1 (3)
C7—C8—C9—C10	−179.5 (2)	C18—C19—C20—C21	−177.5 (3)
C8—C9—C10—C11	−179.8 (3)	C19—C20—C21—S2	−174.9 (2)
C9—C10—C11—C12	−179.9 (3)	C2—C1—S1—H1s	−69 (2)
C10—C11—C12—C13	−180.0 (2)	C20—C21—S2—H2s	−98 (2)

Symmetry codes: (i) −x+3, −y−2, −z+1; (ii) x, y−2, z; (iii) −x+1, −y+4, −z+2.