3,4-Dimethyl-N-[1-(1H-pyrrol-2-yl)ethyl­idene]aniline and the 1-(1-thio­phen-2-yl) analogue

The title compounds, 3,4-dimethyl-N-[1-(1H-pyrrol-2-yl)ethyl­idene]aniline, C₁₄H₁₆N₂, (I), and its analogue 3,4-dimethyl-N-[1-(1-thio­phen-2-yl)ethyl­idene]aniline, C₁₄H₁₅NS, (II), both have basic heterocyclic imino structures showing a planar backbone with similar features, but differing in the hetero­atoms of the five-membered heterocyclic rings, i.e. N in (I) and S in (II). The dihedral angles formed by the five-membered and benzene rings are 81.78 (8) and 75.89 (7)° for (I) and (II), respectively. In (I), centrosymmetric imino­pyrrole dimers are assembled by means of two inverted N—H...N hydrogen bonds and two inverted C—H...π inter­actions. In (II), however, mol­ecules are linked by nonclassical C—H...N hydrogen bonds in which the mol­ecules act as both hydrogen-bond donors and acceptors, resulting in one-dimensional supra­molecular chains.

S1. Introduction

Late transition metal catalysts have attracted much attention in recent years because of their good anti­oxidant properties and outstanding catalytic activities for olefin polymerization (Small et al., 1998; Gibson et al., 1998; Britovsek et al., 2003; Su & Zhao., 2006). Nitro­gen-based ligands, acting as good electron donors, are usually employed as ligand precursors in the preparation of coordination compounds. Recently, the exploration of nitro­gen-based ligands has shifted to the alternative variants of typical bis­(imino)­pyridine, such as pyrimidine, pyrazine, triazine, pyrrole, carbazole, furan and thio­phene (Tenza et al., 2009), in which the central pyridine ring has been replaced by alternative heterocycles. In the research field of five-membered heterocyclic rings, in comparision with the considerable researches about the symmetric bis­(imino)­pyrrole, little attention has been paid to the asymmetric heterocyclic imino derivatives. To the best of our knowledge, only a limited number of mono(imino)­pyrrole compounds have been reported in the literature (Dawson et al., 2000; Anderson et al., 2006; Carabineiro et al., 2007; Pérez-Puente et al., 2008). The case is similar for mono(imino)­thio­phene compounds (Cuesta et al., 2011), in which most of the side arms of the heterocyclic rings were H atoms. To simulate the original structure of a bis­(imino)­pyridine ligand, we chose to replace an H atom with a methyl group and thus prepare new heterocyclic imino compounds. As part of our studies of heterocyclic imino ligands (Su et al., 2009a,b), we have reported the molecular structures of some mono(imino)­pyrrolyl compounds (Su, Li et al., 2012a,b; Su, Qin & Wang, 2012; Su, Qin, Jiao & Wang, 2012; Su et al., 2013).

S2. Experimental

S2.1. Synthesis and crystallization

For the synthesis of compound (I), 2-acetyl­pyrrole (0.2003 g, 1.8354 mmol) and 3,4-di­methyl­aniline (0.4432 g, 3.6574 mmol) were placed in a 50 ml flask. For the synthesis of compound (II), 2-acetyl­thio­phene (0.5966 g, 4.7282 mmol) and 3,4-di­methyl­aniline (1.1275 g, 9.3043 mmol) were placed in a 50 ml flask. A few drops of acetic acid were added and the mixture was subjected to irradiation in a 800 W microwave oven for 3 and 2 min for (I) and (II), respectively, on a medium–heat setting; the colours of both solutions changed from brown to black. The reactions were monitored by thin-layer chromatography (TLC), and the crude products were purified by silica-gel column chromatography (eluant petroleum ether–ethyl acetate, 5:1 v:v). The colourless crystals of (I) and yellow crystals of (II) were both obtained by recrystallization from ethanol and water [for (I), yield 0.1274 g, 32.69%; m.p. 386.6—388.3 K; for (II), yield 0.2962 g, 27.31%, m.p. 341.7—343.3 K]. Crystallization from ethanol and water gave crystals suitable for single-crystal X-ray diffraction.

The purity and the composition of compounds (I) and (II) were checked and characterized by IR spectroscopy, NMR, mass spectrometry and elemental analysis. Data for (I): ν_C═N 1672 cm^-1. ¹H NMR (400 MHz, CDCl₃): δ 7.13 (t, 2H, benzene ring aromatic H), 7.05 (m, 1H, benzene ring aromatic H), 6.68 (d, 1H, pyrrole ring aromatic H), 6.33 (s, 1H, pyrrole ring aromatic H), 6.17 (d, 1H, pyrrole ring aromatic H), 2.08 (s, 6H, benzene-CH₃), 1.89 [s, 3H, –N═ C(CH₃)–]. MS (EI): m/z 212 (M). Analysis calculated for C₁₄H₁₆N₂: C 79.21, H 7.60, N 13.20%; found: C 79.05, H 7.49, N 12.91%. Data for (II), IR (KBr): ν_C═N 1620 cm^-1. ¹H NMR (400 MHz, CDCl₃): δ 7.43 (m, 2H, benzene ring aromatic H), 7.08 (m, 2H, thio­phene ring aromatic H), 6.62 (s, 1H, benzene ring aromatic H), 6.56 (s, 1H, thio­phene ring aromatic H), 2.23 (t, 6H, benzene-CH₃), 2.19 [s, 3H, –N═C(CH₃)–]. MS (EI): m/z 230 (M + H). Analysis calculated for C₁₄H₁₅NS: C 73.32, H 6.59, N 6.11%; found: C 73.36, H 6.80, N 5.92%.

S2.2. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 1. For compounds (I) and (II), all H atoms, except for the N-bound H atoms in (I), were positioned geometrically and treated using a riding model, with C—H = 0.93 and 0.96 Å for aromatic and methyl H atoms, respectively. The displacement parameters of the H atoms were constrained to U_iso(H) = 1.5U_eq(C) for methyl H atoms and 1.2U_eq(C) otherwise. For (I), the N-bound H atoms were located in difference electron-density maps and were refined freely. One reflection, which was clearly an outlier and failed to meet processing requirements, was omitted.

S3. Results and discussion

In this report, we present here the crystal structures of 3,4-di­methyl-N-[1-(1H-pyrrol-2-yl)ethyl­idene]aniline, (I), and its analogue 3,4-di­methyl-N-[1-(1-thio­phen-2-yl)ethyl­idene]aniline, (II). In both compounds, the meta and para positions of the benzene rings are substituted by methyl groups, the only difference between the two compounds being the heteroatoms in the five-membered rings, i.e. N in (I) and S in (II) (see Scheme). The corresponding molecular structures are depicted in Fig. 1. The sum of all the angles around atom C4 is ca 360° in both compounds, indicating the the C4—C5 bond and the five-membered rings are in the same plane. Likewise, the N1—C4—C5—N2 torsion angle of -3.3 (3)° in (I) and the S1—C4—C5—N1 torsion angle of -0.7 (3)° in (II) show that the five-membered rings and the –N═C(CH₃)– groups are nearly coplanar in both cases. For both (I) and (II), the planes of the aromatic substituents on the imine N atoms show dihedral angles of 81.78 (8) and 75.89 (7)° with respect to the plane of the five-membered ring in (I) and (II), respectively. These values are in keeping with the reported trend in our previous work (Su et al., 2013), which is that the benzene rings are rotated about the N_imine—C_ar bond, forming dihedral angles of approximately 80° with the plane of the five-membered ring.

Both (I) and (II) have the basic heterocyclic imino structure, showing a planar backbone with similar features. A brief analysis of the bond lengths and angles in these derivatives (Tables 2 and 3) reveals some noticeable differences in corresponding bond lengths and angles. The C4—C5 bond in (I) is substanti­ally shorter than that in (II), whereas the C5—N2 bond in (I) is obviously longer than the C5—N1 bond in (II). Even so, all the C4—C5 bond lengths, in the range 1.447 (3)–1.466 (3) Å, are slightly shorter than the normal value for a typical Csp²—Csp² single bond (1.476 Å; Allen et al., 1987). Similarly, the C5—N2 and C5—N1 bond lengths, in the range 1.269 (3)–1.284 (3) Å, are slightly shorter than the normal value for a typical Csp²═N double bonds (1.324 Å; Allen et al., 1987), all above facts reveal electron delocalization effects produced from both pyrrole and thio­phene rings towards the –N═C(CH₃)– substituent, in which the delocalization effect of pyrrole ring is relatively strong.

As has been reported before (Su, Li et al., 2012a,b; Su, Qin & Wang, 2012; Su, Qin, Jiao & Wang, 2012; Su et al., 2013), these types of organic derivatives assemble as imino­pyrrole dimers through the formation of two complementary hydrogen bonds between a pyrrole N—H group and the imine N atom belonging to the other molecule of the pair. Besides, the dimers are stabilized by a pair of inter­molecular C—H···π inter­actions between a C—H group bonded to pyrrolyl N atom and the benzene ring belonging to the other molecule of the pair. Accordingly, both inverted N—H···N hydrogen bonds and two inverted C—H···π inter­actions exist in compound (I), which join two molecules in a head-to-tail manner across crystallographic inversion centres to give dimers (Table 4 and Fig. 2). In C—H···π inter­actions, the H···Cg (Cg is the centroid of the benzene rings) distances are 2.76 Å, and the C—H···π angle is 142.2°, the angle of approach of the H···Cg vector to the plane of the aromatic ring is 80.5° and the perpendicular projection of the H atoms onto the pyrrole ring plane is 0.45 Å from the centroid of the ring. It is observed that the H atom lies above the centre of the benzene ring, but the C—H bond points towards a benzene ring C atom. This inter­actions belong to type III according to the classification of Malone et al. (1997). In contrast to the classical hydrogen bonds in (I), examination of the structure with PLATON (Spek, 2009) indicates that there are no classical hydrogen bonds in (II) due to the fact that there is no classical donor (N), whereas nonclassical C—H···Nⁱ hydrogen bonds inter­actions are found in (II) [symmetry codes: (i) -x+1/2, y-1/2, -z+1/2; Table 5 and Fig. 3]. Molecules are linked by nonclassical C—H···N hydrogen bonds in which the molecules play both the roles of hydrogen bond donors and acceptors resulting in one-dimensional supra­molecular chains. Due to the supra­molecular inter­actions described above, the crystal packing shows a zigzag arrangement when viewed along a axis, as depicted in Fig. 3.

Related literature

For related literature, see: Allen et al. (1987); Anderson et al. (2006); Britovsek et al. (2003); Carabineiro et al. (2007); Cuesta et al. (2011); Dawson et al. (2000); Gibson et al. (1998); Malone et al. (1997); Pérez-Puente, de Jesús, Flores & Gómez-Sal (2008); Small et al. (1998); Spek (2009); Su & Zhao (2006); Su et al. (2009a, 2009b, 2012a, 2012b, 2013); Tenza et al. (2009).

Computing details

Data collection: APEX2 (Bruker, 2008) for (I); APEX2 (Bruker,2008) for (II). Cell refinement: SAINT (Bruker, 2008) for (I); SAINT (Bruker,2008) for (II). Data reduction: SAINT (Bruker, 2008 for (I); SAINT (Bruker,2008) for (II). For both compounds, 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: publCIF (Westrip, 2010).

Figures

Fig. 1. The molecular structures of (a) (I) and (b) (II), showing the atom-numbering schemes. Displacement ellipsiods are drawn at 40% probability level. H atoms are presented as a small spheres of arbitrary radius.

Fig. 2. A view of N—H···N and C—H···π interactions (dotted lines) in the crystal structure of (I). H atoms not involved in hydrogen bonding have been omitted for clarity. The largest spheres indicate the centroids of the C7–C11 rings (Cg1). [Symmetry code: (i) -x, -y+1, -z.]

Fig. 3. A view of the unit-cell packing in (II), view along a axis, with the C—H···N bonding scheme shown as dashed lines. H atoms not involved in C—H···N interactions have been omitted for clarity. [Symmetry code: (i) -x+1/2, y-1/2, -z+1/2.]

(I) 3,4-Dimethyl-N-[1-(1H-pyrrol-2-yl)ethylidene]aniline

Crystal data

C14H16N2	F(000) = 456
Mr = 212.29	Dx = 1.139 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 838 reflections
a = 13.013 (3) Å	θ = 2.6–22.5°
b = 10.265 (2) Å	µ = 0.07 mm^−1
c = 9.892 (2) Å	T = 296 K
β = 110.448 (4)°	Block, colourless
V = 1238.2 (4) Å^3	0.37 × 0.26 × 0.15 mm
Z = 4

Data collection

Bruker APEXII CCD diffractometer	2603 independent reflections
Radiation source: fine-focus sealed tube	1344 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.047
ϕ and ω scans	θmax = 26.9°, θmin = 2.6°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −16→7
Tmin = 0.975, Tmax = 0.990	k = −12→13
6774 measured reflections	l = −12→12

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)] = 0.056	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.189	H atoms treated by a mixture of independent and constrained refinement
S = 0.96	w = 1/[σ^2(Fo^2) + (0.1P)^2] where P = (Fo^2 + 2Fc^2)/3
2603 reflections	(Δ/σ)max = 0.001
151 parameters	Δρmax = 0.17 e Å^−3
0 restraints	Δρmin = −0.16 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
N1	−0.17111 (16)	0.46605 (19)	−0.02161 (19)	0.0606 (5)
H1	−0.1169 (19)	0.500 (2)	−0.040 (2)	0.073*
N2	0.03340 (15)	0.40619 (18)	0.18907 (18)	0.0643 (6)
C1	−0.27753 (19)	0.4720 (2)	−0.1073 (3)	0.0723 (7)
H1A	−0.3055	0.5154	−0.1951	0.087*
C2	−0.3370 (2)	0.4029 (3)	−0.0421 (3)	0.0795 (8)
H2	−0.4126	0.3911	−0.0773	0.095*
C3	−0.2642 (2)	0.3534 (3)	0.0862 (3)	0.0748 (7)
H3	−0.2824	0.3022	0.1521	0.090*
C4	−0.15956 (18)	0.3937 (2)	0.0987 (2)	0.0579 (6)
C5	−0.0541 (2)	0.3664 (2)	0.2080 (2)	0.0594 (6)
C6	−0.0547 (2)	0.2908 (3)	0.3394 (3)	0.0915 (9)
H6A	−0.0256	0.2051	0.3377	0.137*
H6B	−0.1286	0.2840	0.3384	0.137*
H6C	−0.0104	0.3353	0.4253	0.137*
C7	0.13719 (19)	0.3741 (2)	0.2936 (2)	0.0601 (6)
C8	0.1881 (2)	0.2577 (2)	0.2830 (2)	0.0744 (7)
H8	0.1532	0.1986	0.2102	0.089*
C9	0.2905 (2)	0.2303 (3)	0.3809 (3)	0.0795 (8)
H9	0.3231	0.1514	0.3731	0.095*
C10	0.34727 (19)	0.3147 (3)	0.4904 (2)	0.0689 (7)
C11	0.2978 (2)	0.4342 (2)	0.4993 (2)	0.0642 (6)
C12	0.1935 (2)	0.4612 (2)	0.4006 (2)	0.0648 (6)
H12	0.1608	0.5404	0.4069	0.078*
C13	0.4574 (2)	0.2778 (3)	0.5978 (3)	0.0988 (9)
H13A	0.4773	0.1926	0.5755	0.148*
H13B	0.4538	0.2775	0.6931	0.148*
H13C	0.5114	0.3398	0.5935	0.148*
C14	0.3561 (2)	0.5324 (3)	0.6135 (3)	0.0956 (9)
H14A	0.3130	0.6105	0.5992	0.143*
H14B	0.4263	0.5521	0.6071	0.143*
H14C	0.3660	0.4970	0.7071	0.143*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0576 (12)	0.0699 (13)	0.0547 (10)	−0.0015 (9)	0.0201 (10)	0.0055 (9)
N2	0.0624 (13)	0.0724 (13)	0.0543 (11)	0.0006 (10)	0.0154 (10)	0.0119 (9)
C1	0.0597 (15)	0.0922 (18)	0.0584 (13)	−0.0008 (13)	0.0123 (13)	0.0062 (13)
C2	0.0620 (15)	0.0979 (19)	0.0698 (15)	−0.0160 (14)	0.0120 (13)	0.0005 (15)
C3	0.0743 (17)	0.0842 (18)	0.0658 (15)	−0.0177 (13)	0.0245 (13)	−0.0011 (13)
C4	0.0655 (15)	0.0582 (13)	0.0489 (11)	−0.0062 (11)	0.0187 (11)	0.0007 (10)
C5	0.0715 (16)	0.0552 (13)	0.0500 (12)	−0.0038 (11)	0.0193 (12)	0.0020 (10)
C6	0.092 (2)	0.109 (2)	0.0698 (16)	−0.0110 (16)	0.0233 (15)	0.0271 (15)
C7	0.0669 (14)	0.0634 (14)	0.0488 (11)	−0.0009 (11)	0.0187 (11)	0.0093 (11)
C8	0.0840 (18)	0.0665 (16)	0.0613 (14)	0.0064 (13)	0.0112 (13)	−0.0031 (12)
C9	0.0881 (19)	0.0778 (17)	0.0681 (15)	0.0203 (15)	0.0217 (14)	−0.0013 (14)
C10	0.0673 (15)	0.0826 (17)	0.0557 (13)	0.0089 (13)	0.0203 (12)	0.0057 (12)
C11	0.0722 (16)	0.0750 (16)	0.0448 (11)	−0.0082 (13)	0.0196 (12)	0.0034 (11)
C12	0.0788 (16)	0.0639 (15)	0.0514 (12)	0.0074 (13)	0.0225 (12)	0.0066 (11)
C13	0.0736 (18)	0.133 (3)	0.0812 (18)	0.0164 (17)	0.0165 (15)	0.0066 (18)
C14	0.117 (2)	0.090 (2)	0.0657 (15)	−0.0132 (17)	0.0139 (16)	−0.0032 (14)

Geometric parameters (Å, º)

N1—C1	1.349 (3)	C7—C8	1.388 (3)
N1—C4	1.366 (3)	C8—C9	1.375 (3)
N1—H1	0.86 (2)	C8—H8	0.9300
N2—C5	1.284 (3)	C9—C10	1.382 (3)
N2—C7	1.423 (3)	C9—H9	0.9300
C1—C2	1.367 (3)	C10—C11	1.403 (3)
C1—H1A	0.9300	C10—C13	1.505 (3)
C2—C3	1.387 (3)	C11—C12	1.395 (3)
C2—H2	0.9300	C11—C14	1.506 (3)
C3—C4	1.387 (3)	C12—H12	0.9300
C3—H3	0.9300	C13—H13A	0.9600
C4—C5	1.447 (3)	C13—H13B	0.9600
C5—C6	1.517 (3)	C13—H13C	0.9600
C6—H6A	0.9600	C14—H14A	0.9600
C6—H6B	0.9600	C14—H14B	0.9600
C6—H6C	0.9600	C14—H14C	0.9600
C7—C12	1.384 (3)
C1—N1—C4	110.39 (19)	C9—C8—C7	119.6 (2)
C1—N1—H1	126.0 (15)	C9—C8—H8	120.2
C4—N1—H1	123.6 (15)	C7—C8—H8	120.2
C5—N2—C7	119.03 (18)	C8—C9—C10	123.0 (2)
N1—C1—C2	107.8 (2)	C8—C9—H9	118.5
N1—C1—H1A	126.1	C10—C9—H9	118.5
C2—C1—H1A	126.1	C9—C10—C11	117.8 (2)
C1—C2—C3	107.7 (2)	C9—C10—C13	120.9 (2)
C1—C2—H2	126.2	C11—C10—C13	121.4 (2)
C3—C2—H2	126.2	C12—C11—C10	119.0 (2)
C2—C3—C4	107.9 (2)	C12—C11—C14	120.3 (2)
C2—C3—H3	126.0	C10—C11—C14	120.7 (2)
C4—C3—H3	126.0	C7—C12—C11	122.2 (2)
N1—C4—C3	106.2 (2)	C7—C12—H12	118.9
N1—C4—C5	122.9 (2)	C11—C12—H12	118.9
C3—C4—C5	130.9 (2)	C10—C13—H13A	109.5
N2—C5—C4	119.17 (19)	C10—C13—H13B	109.5
N2—C5—C6	124.0 (2)	H13A—C13—H13B	109.5
C4—C5—C6	116.9 (2)	C10—C13—H13C	109.5
C5—C6—H6A	109.5	H13A—C13—H13C	109.5
C5—C6—H6B	109.5	H13B—C13—H13C	109.5
H6A—C6—H6B	109.5	C11—C14—H14A	109.5
C5—C6—H6C	109.5	C11—C14—H14B	109.5
H6A—C6—H6C	109.5	H14A—C14—H14B	109.5
H6B—C6—H6C	109.5	C11—C14—H14C	109.5
C12—C7—C8	118.3 (2)	H14A—C14—H14C	109.5
C12—C7—N2	121.4 (2)	H14B—C14—H14C	109.5
C8—C7—N2	120.1 (2)
C4—N1—C1—C2	0.2 (3)	C5—N2—C7—C8	87.4 (3)
N1—C1—C2—C3	−0.3 (3)	C12—C7—C8—C9	2.1 (3)
C1—C2—C3—C4	0.3 (3)	N2—C7—C8—C9	177.1 (2)
C1—N1—C4—C3	0.0 (3)	C7—C8—C9—C10	−0.8 (4)
C1—N1—C4—C5	177.7 (2)	C8—C9—C10—C11	−1.0 (4)
C2—C3—C4—N1	−0.1 (3)	C8—C9—C10—C13	177.8 (2)
C2—C3—C4—C5	−177.6 (2)	C9—C10—C11—C12	1.5 (3)
C7—N2—C5—C4	−177.21 (18)	C13—C10—C11—C12	−177.3 (2)
C7—N2—C5—C6	2.6 (3)	C9—C10—C11—C14	−178.4 (2)
N1—C4—C5—N2	−3.3 (3)	C13—C10—C11—C14	2.7 (3)
C3—C4—C5—N2	173.8 (2)	C8—C7—C12—C11	−1.6 (3)
N1—C4—C5—C6	176.8 (2)	N2—C7—C12—C11	−176.56 (19)
C3—C4—C5—C6	−6.0 (4)	C10—C11—C12—C7	−0.2 (3)
C5—N2—C7—C12	−97.8 (3)	C14—C11—C12—C7	179.7 (2)

Hydrogen-bond geometry (Å, º)

Cg1 is the centroid of the C7–C12 ring.

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···N2^i	0.86 (2)	2.33 (2)	3.122 (3)	154 (2)
C1—H1A···Cg1^i	0.93	2.76	3.537 (6)	142

Symmetry code: (i) −x, −y+1, −z.

(II) 3,4-Dimethyl-N-[1-(1-thiophen-2-yl)ethylidene]aniline

Crystal data

C14H15NS	F(000) = 976
Mr = 229.33	Dx = 1.170 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -C 2yc	Cell parameters from 1387 reflections
a = 11.1481 (15) Å	θ = 2.3–20.8°
b = 13.1309 (18) Å	µ = 0.22 mm^−1
c = 17.839 (2) Å	T = 296 K
β = 94.474 (3)°	Block, yellow
V = 2603.3 (6) Å^3	0.37 × 0.30 × 0.27 mm
Z = 8

Data collection

Bruker APEXII CCD diffractometer	2292 independent reflections
Radiation source: fine-focus sealed tube	1563 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.025
ϕ and ω scans	θmax = 25.0°, θmin = 2.4°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −13→9
Tmin = 0.923, Tmax = 0.942	k = −15→15
6337 measured reflections	l = −18→21

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)] = 0.048	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.173	H-atom parameters constrained
S = 1.07	w = 1/[σ^2(Fo^2) + (0.1P)^2] where P = (Fo^2 + 2Fc^2)/3
2292 reflections	(Δ/σ)max < 0.001
148 parameters	Δρmax = 0.16 e Å^−3
0 restraints	Δρmin = −0.27 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	0.20232 (6)	0.52375 (5)	0.25492 (4)	0.0871 (4)
N1	0.37976 (17)	0.62611 (14)	0.35887 (11)	0.0678 (6)
C1	0.1665 (3)	0.4120 (2)	0.21001 (16)	0.0882 (8)
H1	0.0989	0.4036	0.1766	0.106*
C2	0.2455 (3)	0.3381 (2)	0.22768 (16)	0.0825 (8)
H2	0.2389	0.2726	0.2079	0.099*
C3	0.3407 (2)	0.36991 (19)	0.27980 (14)	0.0727 (7)
H3	0.4031	0.3277	0.2983	0.087*
C4	0.3299 (2)	0.47154 (17)	0.29997 (12)	0.0603 (6)
C5	0.40930 (19)	0.53363 (16)	0.35088 (12)	0.0550 (5)
C6	0.5174 (2)	0.48288 (19)	0.38900 (16)	0.0786 (8)
H6A	0.5516	0.5258	0.4287	0.118*
H6B	0.5759	0.4713	0.3532	0.118*
H6C	0.4943	0.4189	0.4096	0.118*
C7	0.4550 (2)	0.69472 (16)	0.40323 (14)	0.0617 (6)
C8	0.5569 (2)	0.7354 (2)	0.37574 (15)	0.0752 (7)
H8	0.5809	0.7141	0.3295	0.090*
C9	0.6228 (2)	0.8075 (2)	0.41679 (16)	0.0823 (8)
H9	0.6915	0.8338	0.3977	0.099*
C10	0.5907 (2)	0.84183 (19)	0.48493 (16)	0.0737 (7)
C11	0.4879 (2)	0.80154 (18)	0.51412 (14)	0.0695 (7)
C12	0.4204 (2)	0.72907 (19)	0.47157 (14)	0.0679 (6)
H12	0.3506	0.7034	0.4897	0.082*
C13	0.6665 (3)	0.9214 (2)	0.5284 (2)	0.1071 (10)
H13A	0.7326	0.9407	0.5000	0.161*
H13B	0.6969	0.8936	0.5759	0.161*
H13C	0.6180	0.9801	0.5367	0.161*
C14	0.4467 (3)	0.8354 (3)	0.58840 (17)	0.1086 (10)
H14A	0.5100	0.8246	0.6272	0.163*
H14B	0.3771	0.7968	0.5995	0.163*
H14C	0.4265	0.9065	0.5859	0.163*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
S1	0.0852 (6)	0.0742 (5)	0.0967 (6)	−0.0026 (3)	−0.0258 (4)	−0.0070 (3)
N1	0.0632 (12)	0.0535 (11)	0.0835 (14)	−0.0011 (9)	−0.0147 (10)	−0.0011 (9)
C1	0.0889 (19)	0.088 (2)	0.0851 (19)	−0.0266 (17)	−0.0115 (15)	−0.0106 (15)
C2	0.0938 (19)	0.0722 (17)	0.0827 (18)	−0.0243 (16)	0.0137 (15)	−0.0162 (14)
C3	0.0752 (16)	0.0666 (15)	0.0780 (16)	−0.0088 (13)	0.0165 (14)	−0.0089 (12)
C4	0.0634 (14)	0.0582 (14)	0.0597 (14)	−0.0064 (11)	0.0063 (11)	0.0008 (10)
C5	0.0577 (13)	0.0536 (13)	0.0539 (12)	−0.0018 (10)	0.0051 (10)	0.0051 (9)
C6	0.0801 (17)	0.0683 (16)	0.0846 (18)	0.0146 (13)	−0.0117 (14)	−0.0058 (13)
C7	0.0606 (13)	0.0497 (12)	0.0720 (15)	0.0041 (10)	−0.0134 (11)	0.0034 (11)
C8	0.0727 (16)	0.0726 (16)	0.0799 (16)	−0.0064 (13)	0.0037 (13)	−0.0033 (13)
C9	0.0722 (16)	0.0807 (18)	0.094 (2)	−0.0173 (14)	0.0038 (15)	−0.0009 (15)
C10	0.0702 (16)	0.0661 (15)	0.0812 (18)	0.0008 (12)	−0.0180 (14)	0.0057 (13)
C11	0.0748 (16)	0.0634 (14)	0.0677 (15)	0.0129 (12)	−0.0110 (13)	0.0021 (11)
C12	0.0620 (14)	0.0647 (14)	0.0752 (16)	0.0027 (11)	−0.0063 (12)	0.0112 (12)
C13	0.108 (2)	0.087 (2)	0.120 (2)	−0.0198 (18)	−0.0307 (19)	−0.0155 (17)
C14	0.124 (3)	0.120 (3)	0.081 (2)	0.008 (2)	0.0015 (18)	−0.0136 (18)

Geometric parameters (Å, º)

S1—C1	1.704 (3)	C7—C12	1.383 (3)
S1—C4	1.720 (2)	C8—C9	1.374 (3)
N1—C5	1.269 (3)	C8—H8	0.9300
N1—C7	1.428 (3)	C9—C10	1.370 (4)
C1—C2	1.331 (4)	C9—H9	0.9300
C1—H1	0.9300	C10—C11	1.399 (4)
C2—C3	1.418 (4)	C10—C13	1.518 (4)
C2—H2	0.9300	C11—C12	1.399 (3)
C3—C4	1.390 (3)	C11—C14	1.503 (4)
C3—H3	0.9300	C12—H12	0.9300
C4—C5	1.466 (3)	C13—H13A	0.9600
C5—C6	1.494 (3)	C13—H13B	0.9600
C6—H6A	0.9600	C13—H13C	0.9600
C6—H6B	0.9600	C14—H14A	0.9600
C6—H6C	0.9600	C14—H14B	0.9600
C7—C8	1.379 (3)	C14—H14C	0.9600
C1—S1—C4	91.79 (14)	C9—C8—H8	120.1
C5—N1—C7	121.31 (19)	C7—C8—H8	120.1
C2—C1—S1	112.9 (2)	C10—C9—C8	122.3 (2)
C2—C1—H1	123.5	C10—C9—H9	118.9
S1—C1—H1	123.5	C8—C9—H9	118.9
C1—C2—C3	112.8 (2)	C9—C10—C11	118.9 (2)
C1—C2—H2	123.6	C9—C10—C13	120.4 (3)
C3—C2—H2	123.6	C11—C10—C13	120.7 (3)
C4—C3—C2	112.1 (2)	C10—C11—C12	118.5 (2)
C4—C3—H3	123.9	C10—C11—C14	122.1 (3)
C2—C3—H3	123.9	C12—C11—C14	119.4 (3)
C3—C4—C5	129.4 (2)	C7—C12—C11	121.7 (2)
C3—C4—S1	110.30 (18)	C7—C12—H12	119.2
C5—C4—S1	120.34 (17)	C11—C12—H12	119.2
N1—C5—C4	116.9 (2)	C10—C13—H13A	109.5
N1—C5—C6	125.7 (2)	C10—C13—H13B	109.5
C4—C5—C6	117.4 (2)	H13A—C13—H13B	109.5
C5—C6—H6A	109.5	C10—C13—H13C	109.5
C5—C6—H6B	109.5	H13A—C13—H13C	109.5
H6A—C6—H6B	109.5	H13B—C13—H13C	109.5
C5—C6—H6C	109.5	C11—C14—H14A	109.5
H6A—C6—H6C	109.5	C11—C14—H14B	109.5
H6B—C6—H6C	109.5	H14A—C14—H14B	109.5
C8—C7—C12	118.8 (2)	C11—C14—H14C	109.5
C8—C7—N1	120.8 (2)	H14A—C14—H14C	109.5
C12—C7—N1	120.2 (2)	H14B—C14—H14C	109.5
C9—C8—C7	119.9 (2)
C4—S1—C1—C2	0.3 (2)	C5—N1—C7—C12	−109.2 (3)
S1—C1—C2—C3	0.1 (3)	C12—C7—C8—C9	1.0 (4)
C1—C2—C3—C4	−0.5 (3)	N1—C7—C8—C9	174.8 (2)
C2—C3—C4—C5	−179.0 (2)	C7—C8—C9—C10	−0.4 (4)
C2—C3—C4—S1	0.7 (3)	C8—C9—C10—C11	0.6 (4)
C1—S1—C4—C3	−0.52 (19)	C8—C9—C10—C13	179.8 (2)
C1—S1—C4—C5	179.16 (19)	C9—C10—C11—C12	−1.4 (3)
C7—N1—C5—C4	−175.8 (2)	C13—C10—C11—C12	179.4 (2)
C7—N1—C5—C6	4.4 (4)	C9—C10—C11—C14	−179.9 (2)
C3—C4—C5—N1	178.9 (2)	C13—C10—C11—C14	0.9 (4)
S1—C4—C5—N1	−0.7 (3)	C8—C7—C12—C11	−1.8 (3)
C3—C4—C5—C6	−1.3 (3)	N1—C7—C12—C11	−175.6 (2)
S1—C4—C5—C6	179.07 (17)	C10—C11—C12—C7	2.0 (3)
C5—N1—C7—C8	77.1 (3)	C14—C11—C12—C7	−179.4 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
C2—H2···N1^i	0.93	2.57	3.428 (3)	153

Symmetry code: (i) −x+1/2, y−1/2, −z+1/2.