2,9-Dimethyl-3,8-bis(methyl­sulfanyl)naphtho[2,1-b:3,4-b′]difuran

The title compound, C₁₈H₁₆O₂S₂, was prepared by the Lewis acid-catalysed reaction of 2,3-dihydroxy­naphthalene with α-chloro-α-(methyl­sulfan­yl)acetone. The naphtho[2,1-b:3,4-b′]difuran unit is nearly planar, with a mean deviation from the least-squares plane of 0.028 Å. In the crystal structure, aromatic π–π stacking inter­actions are observed between adjacent mol­ecules.

Key indicators

• Single-crystal X-ray study
• T = 298 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.078
• wR factor = 0.201
• Data-to-parameter ratio = 18.1

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          6
PLAT380_ALERT_4_C Check Incorrectly? Oriented X(sp2)-Methyl Moiety        C18

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   2 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
   0 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
   1 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: STADI4 (Stoe & Cie, 1996); cell refinement: STADI4; data reduction: X-RED32 (Stoe & Cie, 1996); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3 (Farrugia, 1997) and DIAMOND (Brandenburg, 1998); software used to prepare material for publication: SHELXL97.

2,9-Dimethyl-3,8-dimethylsulfanylnaphtho[2,1 - b:3,4 - b']difuran

Crystal data

C18H16O2S2	F(000) = 688
Mr = 328.43	Dx = 1.361 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71069 Å
Hall symbol: -P 2ybc	Cell parameters from 22 reflections
a = 7.564 (2) Å	θ = 9.5–10.1°
b = 20.415 (5) Å	µ = 0.34 mm^−1
c = 11.022 (1) Å	T = 298 K
β = 109.60 (1)°	Tetragonal prism, pale red
V = 1603.4 (6) Å^3	0.42 × 0.12 × 0.10 mm
Z = 4

Data collection

Stoe Stadi-4 diffractometer	Rint = 0.000
Radiation source: fine-focus sealed tube	θmax = 27.4°, θmin = 2.0°
Graphite monochromator	h = −9→9
ω/2θ scans	k = 0→26
3644 measured reflections	l = 0→14
3644 independent reflections	3 standard reflections every 60 min
2179 reflections with I > 2σ(I)	intensity decay: 2.4%

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)] = 0.078	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.201	H-atom parameters constrained
S = 1.10	w = 1/[σ^2(Fo^2) + (0.0635P)^2 + 2.5272P] where P = (Fo^2 + 2Fc^2)/3
3644 reflections	(Δ/σ)max < 0.001
201 parameters	Δρmax = 0.51 e Å^−3
0 restraints	Δρmin = −0.34 e Å^−3

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
S1	0.20290 (19)	0.38060 (6)	0.49028 (13)	0.0502 (4)
S2	0.49008 (19)	−0.01472 (7)	0.74457 (15)	0.0590 (4)
O1	0.0461 (4)	0.20575 (14)	0.3395 (3)	0.0407 (7)
O2	0.1579 (4)	0.06738 (14)	0.4258 (3)	0.0442 (8)
C1	0.1655 (6)	0.1870 (2)	0.4582 (4)	0.0364 (9)
C2	0.2164 (6)	0.1230 (2)	0.4977 (4)	0.0375 (9)
C3	0.2469 (7)	0.0166 (2)	0.5047 (5)	0.0461 (11)
C4	0.3540 (6)	0.0383 (2)	0.6225 (5)	0.0432 (11)
C5	0.3370 (6)	0.1094 (2)	0.6202 (4)	0.0369 (10)
C6	0.4148 (6)	0.1626 (2)	0.7086 (4)	0.0373 (10)
C7	0.5353 (6)	0.1521 (2)	0.8367 (4)	0.0452 (11)
H7	0.5663	0.1095	0.8660	0.054*
C8	0.6067 (7)	0.2035 (3)	0.9177 (5)	0.0511 (12)
H8	0.6845	0.1956	1.0018	0.061*
C9	0.5634 (7)	0.2681 (3)	0.8748 (5)	0.0545 (13)
H9	0.6144	0.3028	0.9302	0.065*
C10	0.4471 (7)	0.2805 (2)	0.7523 (5)	0.0465 (11)
H10	0.4200	0.3236	0.7253	0.056*
C11	0.3671 (6)	0.2287 (2)	0.6657 (4)	0.0356 (9)
C12	0.2384 (6)	0.2399 (2)	0.5365 (4)	0.0359 (9)
C13	0.1573 (6)	0.2967 (2)	0.4582 (4)	0.0382 (10)
C14	0.0451 (6)	0.2733 (2)	0.3427 (4)	0.0412 (10)
C15	0.2061 (8)	−0.0497 (2)	0.4455 (6)	0.0607 (15)
H15A	0.2360	−0.0506	0.3674	0.073*
H15B	0.0755	−0.0596	0.4264	0.073*
H15C	0.2806	−0.0817	0.5045	0.073*
C16	0.3228 (9)	−0.0371 (3)	0.8217 (6)	0.0731 (17)
H16A	0.3809	−0.0665	0.8917	0.110*
H16B	0.2169	−0.0582	0.7604	0.110*
H16C	0.2818	0.0016	0.8542	0.110*
C17	0.0490 (8)	0.4012 (3)	0.5788 (6)	0.0660 (15)
H17A	0.0631	0.4467	0.6017	0.099*
H17B	0.0805	0.3751	0.6555	0.099*
H17C	−0.0786	0.3927	0.5263	0.099*
C18	−0.0747 (7)	0.3057 (3)	0.2228 (5)	0.0532 (13)
H18A	−0.2024	0.2918	0.2035	0.064*
H18B	−0.0320	0.2939	0.1529	0.064*
H18C	−0.0671	0.3523	0.2342	0.064*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0607 (8)	0.0335 (6)	0.0598 (8)	−0.0017 (5)	0.0246 (6)	0.0044 (6)
S2	0.0494 (7)	0.0474 (7)	0.0813 (10)	0.0123 (6)	0.0236 (7)	0.0222 (7)
O1	0.0464 (18)	0.0397 (17)	0.0321 (16)	0.0021 (13)	0.0079 (14)	0.0015 (13)
O2	0.0500 (19)	0.0344 (16)	0.0474 (18)	−0.0041 (14)	0.0151 (15)	−0.0063 (14)
C1	0.037 (2)	0.040 (2)	0.030 (2)	0.0000 (18)	0.0077 (18)	0.0050 (18)
C2	0.039 (2)	0.034 (2)	0.041 (2)	−0.0055 (18)	0.016 (2)	−0.0022 (19)
C3	0.051 (3)	0.032 (2)	0.062 (3)	−0.002 (2)	0.027 (2)	0.000 (2)
C4	0.041 (2)	0.038 (2)	0.054 (3)	0.0047 (19)	0.020 (2)	0.008 (2)
C5	0.036 (2)	0.033 (2)	0.043 (2)	0.0019 (17)	0.0144 (19)	0.0061 (18)
C6	0.030 (2)	0.044 (2)	0.038 (2)	−0.0005 (18)	0.0107 (19)	0.0018 (19)
C7	0.039 (2)	0.055 (3)	0.039 (3)	0.006 (2)	0.010 (2)	0.009 (2)
C8	0.044 (3)	0.063 (3)	0.038 (3)	0.000 (2)	0.002 (2)	−0.002 (2)
C9	0.055 (3)	0.056 (3)	0.043 (3)	−0.008 (2)	0.004 (2)	−0.013 (2)
C10	0.049 (3)	0.040 (2)	0.046 (3)	−0.005 (2)	0.010 (2)	−0.005 (2)
C11	0.034 (2)	0.039 (2)	0.033 (2)	−0.0008 (17)	0.0107 (18)	0.0012 (18)
C12	0.037 (2)	0.034 (2)	0.039 (2)	0.0012 (18)	0.0156 (19)	0.0033 (18)
C13	0.043 (2)	0.034 (2)	0.039 (2)	0.0007 (18)	0.015 (2)	0.0041 (18)
C14	0.045 (2)	0.041 (2)	0.038 (2)	0.005 (2)	0.014 (2)	0.0087 (19)
C15	0.068 (4)	0.036 (3)	0.087 (4)	−0.003 (2)	0.039 (3)	−0.010 (3)
C16	0.076 (4)	0.077 (4)	0.072 (4)	0.012 (3)	0.033 (3)	0.031 (3)
C17	0.066 (4)	0.058 (3)	0.080 (4)	0.001 (3)	0.032 (3)	−0.014 (3)
C18	0.058 (3)	0.056 (3)	0.044 (3)	0.012 (2)	0.014 (2)	0.012 (2)

Geometric parameters (Å, º)

S1—C13	1.760 (4)	C9—C10	1.365 (7)
S1—C17	1.801 (5)	C9—H9	0.9300
S2—C4	1.764 (5)	C10—C11	1.417 (6)
S2—C16	1.804 (6)	C10—H10	0.9300
O1—C1	1.371 (5)	C11—C12	1.448 (6)
O1—C14	1.379 (5)	C12—C13	1.453 (6)
O2—C2	1.370 (5)	C13—C14	1.358 (6)
O2—C3	1.375 (5)	C14—C18	1.484 (6)
C1—C12	1.376 (6)	C15—H15A	0.9600
C1—C2	1.390 (6)	C15—H15B	0.9600
C2—C5	1.381 (6)	C15—H15C	0.9600
C3—C4	1.354 (7)	C16—H16A	0.9600
C3—C15	1.489 (6)	C16—H16B	0.9600
C4—C5	1.457 (6)	C16—H16C	0.9600
C5—C6	1.446 (6)	C17—H17A	0.9600
C6—C7	1.416 (6)	C17—H17B	0.9600
C6—C11	1.434 (6)	C17—H17C	0.9600
C7—C8	1.367 (7)	C18—H18A	0.9600
C7—H7	0.9300	C18—H18B	0.9600
C8—C9	1.403 (7)	C18—H18C	0.9600
C8—H8	0.9300
C13—S1—C17	102.5 (2)	C10—C11—C6	118.4 (4)
C4—S2—C16	101.1 (2)	C10—C11—C12	122.7 (4)
C1—O1—C14	105.2 (3)	C6—C11—C12	119.0 (4)
C2—O2—C3	105.3 (3)	C1—C12—C11	119.3 (4)
O1—C1—C12	112.1 (4)	C1—C12—C13	104.6 (4)
O1—C1—C2	125.8 (4)	C11—C12—C13	136.1 (4)
C12—C1—C2	122.0 (4)	C14—C13—C12	106.4 (4)
O2—C2—C5	112.2 (4)	C14—C13—S1	123.3 (3)
O2—C2—C1	126.6 (4)	C12—C13—S1	130.0 (3)
C5—C2—C1	121.2 (4)	C13—C14—O1	111.6 (4)
C4—C3—O2	111.6 (4)	C13—C14—C18	133.0 (4)
C4—C3—C15	133.4 (5)	O1—C14—C18	115.4 (4)
O2—C3—C15	115.0 (4)	C3—C15—H15A	109.5
C3—C4—C5	106.7 (4)	C3—C15—H15B	109.5
C3—C4—S2	122.6 (4)	H15A—C15—H15B	109.5
C5—C4—S2	130.5 (4)	C3—C15—H15C	109.5
C2—C5—C6	119.6 (4)	H15A—C15—H15C	109.5
C2—C5—C4	104.1 (4)	H15B—C15—H15C	109.5
C6—C5—C4	136.3 (4)	S2—C16—H16A	109.5
C7—C6—C11	118.6 (4)	S2—C16—H16B	109.5
C7—C6—C5	122.5 (4)	H16A—C16—H16B	109.5
C11—C6—C5	118.9 (4)	S2—C16—H16C	109.5
C8—C7—C6	121.0 (4)	H16A—C16—H16C	109.5
C8—C7—H7	119.5	H16B—C16—H16C	109.5
C6—C7—H7	119.5	S1—C17—H17A	109.5
C7—C8—C9	120.4 (4)	S1—C17—H17B	109.5
C7—C8—H8	119.8	H17A—C17—H17B	109.5
C9—C8—H8	119.8	S1—C17—H17C	109.5
C10—C9—C8	120.5 (4)	H17A—C17—H17C	109.5
C10—C9—H9	119.8	H17B—C17—H17C	109.5
C8—C9—H9	119.8	C14—C18—H18A	109.5
C12^i—C9—H9	84.7	C14—C18—H18B	109.5
C1^i—C9—H9	80.4	H18A—C18—H18B	109.5
C9—C10—C11	121.1 (5)	C14—C18—H18C	109.5
C9—C10—H10	119.4	H18A—C18—H18C	109.5
C11—C10—H10	119.4	H18B—C18—H18C	109.5
O1^i—C10—H10	83.8

Symmetry code: (i) x, −y+1/2, z+1/2.