A non-solvated form of [(Z)-O-methyl-N-(2-methyl­phen­yl)­thio­carbamato-κS](tri­phenyl­phosphane-κP)gold(I): crystal structure and Hirshfeld surface analysis

Yeo, C.I.; Tan, S.L.; Tiekink, E.R.T.

doi:10.1107/S2056989016014419

research communications

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ISSN: 2056-9890

Volume 72| Part 10| October 2016| Pages 1446-1452

https://doi.org/10.1107/S2056989016014419

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A non-solvated form of [(Z)-O-methyl-N-(2-methylphenyl)thiocarbamato-κS](triphenylphosphane-κP)gold(I): crystal structure and Hirshfeld surface analysis

Chien Ing Yeo,^a Sang Loon Tan ^a and Edward R. T. Tiekink ^a ^*

^aResearch Centre for Crystalline Materials, Faculty of Science and Technology, Sunway University, 47500 Bandar Sunway, Selangor Darul Ehsan, Malaysia
^*Correspondence e-mail: edwardt@sunway.edu.my

Edited by W. T. A. Harrison, University of Aberdeen, Scotland (Received 9 September 2016; accepted 10 September 2016; online 16 September 2016)

The title compound, [Au(C₉H₁₀NOS)(C₁₈H₁₅P)], features a near linear P—Au—S arrangement defined by phosphane P and thiolate S atoms with the minor distortion from the ideal [P—Au—S is 177.61 (2)°] being traced in part to the close intramolecular approach of an O atom [Au⋯O = 3.040 (2) Å]. The packing features supramolecular layers lying parallel to (011) sustained by a combination of C—H⋯π and π–π [inter-centroid distance = 3.8033 (17) Å] interactions. The molecular structure and packing are compared with those determined for a previously reported hemi-methanol solvate [Kuan et al. (2008 ). CrystEngComm, 10, 548–564]. Relatively minor differences are noted in the conformations of the rings in the Au-containing molecules. A Hirshfeld surface analysis confirms the similarity in the packing with the most notable differences relating to the formation of C—H⋯S contacts between the constituents of the solvate.

Keywords: crystal structure; gold; thiocarbamate; solvatomorphs; Hirshfeld surface analysis.

CCDC reference: 1503822

1. Chemical context

Triorganophosphanegold(I) carbonimidothioates, i.e. molecules of the general formula R₃PAu[SC(OR′)=NR′′ for R, R′ and R′′ = alkyl, aryl, were first described in 1993 as were the crystal and molecular structures of archetypal Ph₃PAu[SC(OMe)=NPh (Hall et al., 1993 ). Since then, approximately 70 crystal structures, including those of bidentate phosphanes and bipodal analogues, have been described in the crystallographic literature (Groom et al., 2016 ). The interest in phosphanegold(I) carbonimidothioates stems from two distinct considerations related to their relatively facile synthesis, their long-term stability and their readiness to crystallize, namely crystal engineering and evaluation for biological activity. In the former and reflecting their propensity to form diffraction-quality crystals, an unprecedented comprehensive series of compounds, R₃PAu[SC(OMe)=NC₆H₄NO₂-p] (R = Et, Cy and Ph), and bidentate phosphane analogues, Ph₂P–(CH₂)_n–PPh₂ for n = 1–4 and for when the bridge is ferrocenyl, enabled correlations between the formation of Au⋯Au (aurophilic) interactions and solid-state luminescence responses (Ho et al., 2006 ). In another series of compounds where the diphosphane ligand was held constant, i.e. [(Ph₂P(CH₂)₄PPh₂){AuSC(OR′)=NC₆H₄Y-p}₂] for R′ = Me, Et or iPr and Y = H, NO₂ or Me, the packing was assessed in terms of delineating the influence of R′ and Y substituents (Ho & Tiekink, 2007 ). In yet another systematic series of compounds, i.e. of the general formula R₃PAu[SC(OMe)=NR′′], for R = Ph, o-tol, m-tol or p-tol, and R′′ = Ph, o-tol, m-tol, p-tol or C₆H₄NO₂-p, it was possible to assess the impact of steric and electronic effects upon the formation of intramolecular Au⋯O or Au⋯π(N-bound ring) interactions (Kuan et al., 2008). Over and above these studies, phosphanegold(I) carbonimidothioates exhibit promising biological potential in the context of anti-cancer activity (Yeo, Ooi et al., 2013 ; Ooi et al., 2015 ) and anti-microbial activity (Yeo, Sim et al., 2013 ). Just as systematic variations in the substituents influences the molecular packing, this also influences biological effects so that, for example, different apoptotic mechanisms of cell death are induced when the O-bound R′ is varied. It was in fact during biological investigations that the title compound, Ph₃PAu[SC(OMe)=N(o-tol)] (I), was prepared once again, having been previously characterized as a 1:1 hemi-methanol solvate (I·0.5MeOH; Kuan et al., 2008). Herein, the crystal and molecular structures of (I) are described along with Hirshfeld surface analyses of both (I) and (I·0.5MeOH).

2. Structural commentary

The gold(I) atom in (I), Fig. 1, exists within the anticipated linear geometry defined by thiolate-S1 and phosphane-P1 atoms. Support for the `thiolate-S1' assignment comes about by the elongation of the C1—S1 bond to 1.768 (3) Å, Table 1, c.f. 1.6700 (14) Å, and contraction of the C1—N1 bond in (I) to 1.260 (3) Å, c.f. 1.3350 (15) Å in the structure of the non-coordinating molecule, i.e. S=C(OMe)N(H)(o-tol) (Kuan et al., 2005 ). The small deviation from linearity about the gold(I) atom [P—Au—S = 177.61 (2)°] may be related to the close approach of the O1 atom, Au⋯O1 is 3.040 (2)°, as the carbonimidothioate ligand is orientated to place the oxygen atom in close proximity to the gold atom, Fig. 1. There are also significant differences in key angles between the coordinating and non-coordinating forms of the ligand, especially about the C1 atom. These reflect the reorganization of π-electron density manifested in the C=N and C=S bonds, respectively. Thus, the widest angles in the anion involve C=N and those in the free molecule, involve C=S. A relatively large change is noted for the C1—N1—C2 angles, i.e. 121.4 (2) and 127.11 (12)°, respectively, for the coordinating and non-coordinating ligands, which is a result of the presence of the acidic proton in the latter. In terms of conformation of the anion in (I), the central residue comprising the S1, O1, N1 and C1 atom is strictly planar (r.m.s. deviation of the fitted atoms = 0.0091 Å), with the pendent C2 and C9 atoms lying 0.035 (4) and 0.198 (4) Å out of this plane, respectively. The dihedral angle between the central residue and the N-bound aryl ring is 85.08 (7)°, indicating a nearly perpendicular arrangement; in the free ligand the comparable angle is 51.84 (6)° (Kuan et al., 2005).

Table 1
Selected geometric data (Å, °) for (I) and (I·0.5MeOH)^a

Parameter	(I)	(I·0.5MeOH)
Au—S1	2.3114 (6)	2.3009 (17)
Au—P1	2.2529 (6)	2.2558 (15)
C1—S1	1.768 (3)	1.751 (7)
C1—O1	1.359 (3)	1.356 (9)
C1—N1	1.260 (3)	1.260 (8)
Au⋯O1	3.040 (2)	3.093 (5)
S1—Au—P1	177.61 (2)	175.52 (6)
Au—S1—C1	103.14 (9)	105.0 (2)
C1—O1—C9	114.9 (2)	116.3 (5)
C1—N1—C2	121.4 (2)	121.2 (6)
S1—C1—O1	113.38 (18)	113.5 (4)
S1—C1—N1	125.9 (2)	126.0 (6)
O1—C1—N1	120.7 (2)	120.5 (6)
Note: (a) Kuan et al. (2008).

Figure 1
Molecular structure of (I)

, showing the atom-labelling scheme and displacement ellipsoids at the 70% probability level.

Salient geometric parameters for (I·0.5MeOH) (Kuan et al., 2008) are also included in Table 1. From these data, it is apparent there are no great variations between the structures with perhaps the exception of the Au—S1 bond length in (I) being 0.01 Å longer than in (I·0.5MeOH). In terms of angles, the angle subtended at the S1 atom is about 2° tighter in (I). The intramolecular Au⋯O1 separation is 0.05 Å shorter in (I) but the deviation from linearity is less, reflecting the weak nature of this interaction.

Fig. 2 shows an overlay diagram for (I) and I in (I·0.5MeOH). From this it can be seen there is evidently a close overlap of all but the aryl rings that display orientational differences.

Figure 2
Overlay diagram of (I)

(red image) and I in (I·0.5MeOH) (blue). The molecules have been overlapped so that the S1, O1 and N1 atoms are coincident.

3. Supramolecular features

In the crystal of (I), the most prominent points of contact between molecules are of the type C—H⋯π and π–π, Table 2. Thus, centrosymmetrically related o-tolyl residues associate via pairs of methyl-C—H⋯π(o-tol) interactions, and centrosymmetrically related phosphane ligands are connected via face-to-face π–π interactions involving one of the P-bound phenyl rings only. The result is the formation of supramolecular layers lying parallel to (011) as illustrated in Fig. 3a. The layers stack with no directional interactions between them, Fig. 3b.

Table 2
Hydrogen-bond geometry (Å, °)

Cg1 and Cg2 are the centroids of the (C2–C7) and (C22–C27) rings, respectively.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C8—H8C⋯Cg1ⁱ	0.98	2.73	3.481 (3)	134
Cg2⋯Cg2ⁱⁱ	–	–	3.8033 (17)	–
Symmetry codes: (i) -x, -y+2, -z; (ii) -x+1, -y+1, -z+1.

Figure 3
Molecular packing in (I)

: (a) a view of the supramolecular layer sustained by C—H⋯π and π–π contacts, shown as purple and orange dashed lines, respectively, and (b) a view of the unit-cell contents shown in projection down the a axis, highlighting the stacking of (011) layers.

The packing of (I·0.5MeOH) is also characterized by supramolecular layers. These are sustained by π–π interactions of 3.687 (4) Å between centrosymmetrically related molecules in a face-to-face fashion, as for (I), and by phenyl- and o-tolyl-C—H⋯π(P-phenyl) interactions. The layers stack along the b axis devoid of specific interactions between successive layers. This arrangement defines columns along the a axis in which reside the disordered methanol molecules, Fig. 4. The partially occupied methanol molecules in (I·0.5MeOH), disordered over a centre of inversion, are connected to the host framework via methyl-C—H⋯S interactions.

Figure 4
Molecular packing in (I·0.5MeOH): a view of the unit-cell contents shown in projection down the a axis. The C—H⋯S, C—H⋯π and π–π contacts are shown as orange, purple and blue dashed lines, respectively. The methanol molecules are highlighted in space-filling mode.

4. Analysis of the Hirshfeld surfaces

Hirshfeld surface analysis and fingerprint plots were undertaken to study the intermolecular contacts and topological differences between (I) and its methanol hemi-solvate, (I·0.5MeOH). Briefly, the internal (d_i) and external (d_e) distances of atomic surface points to the nearest nucleus were computed for the molecules in both (I) and (I·0.5MeOH) (Spackman & Jayatilaka, 2009 ; McKinnon et al., 2007 ). The resulting normalized contact distances (d_norm) were mapped on the Hirshfeld surface in the range −1.04 to 1.91 Å. The contact distances shorter than the sum of van der Waals radii are highlighted in red while distances equal to or longer than the sum of van der Waals radii are shown in white and blue, respectively (McKinnon et al., 2007). The combination of d_i and d_e in intervals of 0.01 Å result in the two-dimensional fingerprint plots, where the different colours on the fingerprint plots represent the probability of occurrence, ranging from blue (few points) through green to red (many points) (Spackman & McKinnon, 2002 ). All analyses were performed using Crystal Explorer (Wolff et al., 2012 ).

The number of Hirshfeld surfaces that are unique in a given crystal structure depends on the number of independent molecules in the asymmetric unit (Fabbiani et al., 2007 ). For this reason, the Hirshfeld surfaces for (I·0.5MeOH) were modelled separately for (I) and for MeOH, while the Hirshfeld surface of (I·0.5MeOH), as a whole, were also included for a thorough comparison of the molecular packing in (I) and (I·0.5MeOH).

Fig. 5a and 5b show the front and back views of Hirshfeld surfaces for (I), (I·0.5MeOH) as well as for I in (I·0.5MeOH) which are displayed in approximately the same orientation. Despite the presence of additional solvent molecule in (I·0.5MeOH), both this and (I) are governed by similar intermolecular contacts as can be observed through the appearance of several red spots on the Hirshfeld surfaces of both structures. These are mainly attributed to H⋯H, C⋯H/H⋯C and S⋯H/H⋯S contacts. However, a close inspection of the Hirshfeld surface of I in (I·0.5MeOH) reveals a stark difference as compared to (I), in that evidence is found for a close contact through a S⋯H interaction with the solvent MeOH molecule as readily seen from the intense red spot in Fig. 5a – right. Apart from this contact, I in (I·0.5MeOH) also forms weak interaction, as demonstrated by the less intense red spot in Fig. 5b – right, through O⋯H with another molecule of I but beyond the sum of their van der Waals radii (Spek, 2009 ).

Figure 5
Comparison between (I)

, (I·0.5MeOH) and I in (I·0.5MeOH) of (a) the front view of the complete Hirshfeld surface, (b) the back view of the complete Hirshfeld surface, (c) the front view of the curvedness and (d) the back view of the curvedness.

In view that the conformational flexibility highlighted in Fig. 2, the mapping of curvedness over the Hirshfeld surface was undertaken in order to correlate these with some physicochemical properties. Fig. 5c and 5d show the front and back views of the curvedness for (I), (I·0.5MeOH) and I in (I·0.5MeOH). From these views, it is clear (I) exhibits a relatively broad region of curvedness surface, Fig. 5c – left. It is presumably for this reason that (I) has a relatively greater surface area, indicating a more compact conformation, i.e. having a lower volume, and is more densely packed than I in (I·0.5MeOH), see data in Table 3. Interestingly, it seems the molecular shape exerts a great influence over the intermolecular interactions and the density of the resultant crystal structures, Table 3. The packing efficiency of (I) is also greater than that of (I·0.5MeOH), suggesting that the incorporation of methanol in the molecular packing of (I·0.5MeOH) is not directed by the need to fill otherwise free space in (I).

Table 3
Physiochemical properties for (I), (I·0.5MeOH), and I and MeOH in (I·0.5MeOH)

Parameter	(I)	(I·0.5MeOH)
		I	MeOH
Volume, V (Å³)	590.16	637.63	591.04
Surface area, A (Å²)	514.76	543.39	512.10
A:V (Å⁻¹)	0.87	0.85	0.87
Globularity, G	0.661	0.659	0.665
Asphericity, Ω	0.159	0.100	0.138
Density (g cm⁻¹)	1.767	1.658	–
Packing index (%)	68.2	67.3	–

The complete two-dimensional fingerprint plots for (I), (I·0.5MeOH) and, for additional comparison, I in (I·0.5MeOH), along with the decomposed two-dimensional plots for the indicated interactions are presented in Fig. 6, while the percentage contributions are represented graphically in Fig. 7. As mentioned previously, molecules of (I) in its unsolvated and solvated forms are governed by similar intermolecular close contacts which mainly comprise non-hydrogen-bond interactions. Specifically, H⋯H, being the most dominant interaction among all, ca 57.3% in (I) and 55.4% in (I·0.5MeOH), forms a forceps-like fingerprint in (I), by contrast to the distinctive spike of (I·0.5MeOH), Fig. 6b. It is noted there is not much to distinguish the fingerprint patterns due to C⋯H/H⋯C, Fig. 6c. This observation is vindicated by the near equivalence of the sums of the d_e + d_i distances of ∼2.70 Å for (I) and ∼2.64 Å for (I·0.5MeOH) and with the relative contributions of approximately 23.3 and 23.8% to the overall surface areas, respectively. However, a marked difference is observed in the corresponding pincers-like fingerprint plots due to S⋯H/H⋯S interactions, Fig. 6d. Thus, the plot for (I) displays a sum of intermolecular contact distance d_e + d_i of ∼2.88 Å, originating from weak phenyl-C–H⋯S contacts. For the solvate, a mixed interaction mode is evident from the asymmetric fingerprint plot indicating interactions between two chemically and crystallographically distinct molecules, i.e. the relatively strong solvent⋯solute methyl-C—H⋯S interaction with the sum of d_e + d_i distances being ∼2.42 Å coupled with a weak methoxy-C—H⋯S contact with d_e + d_i = ∼3.1 Å. Such interactions contribute roughly 3.2% (S⋯H–solvent) and 1.1% (S⋯H–methoxy) to the total 4.3% to the overall Hirshfeld surface of I in (I·0.5MeOH) compared to a ∼7.5% contribution in (I). Molecule (I) does not forms any meaningful contacts through O⋯H/H⋯O owing to their long contact distances despite these contacts constituting approximately 2.4% of the overall contacts on the Hirshfeld surface, Fig. 6e. Upon crystallization with methanol solvent, the overall contribution increases to 6.4% with the sum of d_e + d_i of ∼2.50 Å which is considered longer than typical O⋯H interactions with distances of ∼2.14 Å (Gavezzotti, 2016 ).

Figure 6
Comparison between (I)

, (I·0.5MeOH) and I in (I·0.5MeOH) of (a) the full fingerprint plots, and delineated two-dimensional plots associated with (b) H⋯H, (c) C⋯H/H⋯C, (d) S⋯H/H⋯S and (e) O⋯H/H⋯O contacts.

Figure 7
Percentage contribution of different close contacts to the Hirshfeld surface of forms (I)

, (I·0.5MeOH), I in (I·0.5MeOH) and MeOH in (I·0.5MeOH).

5. Database survey

As mentioned in the Chemical context, there are over 70 molecular structures in the crystallographic literature (Groom et al., 2016) based on the general formula R₃PAu[SC(OR′)=NR′′ for R, R′ and R′′ = alkyl, aryl. The present structural pair, (I) and (I·0.5MeOH) represents the second example of solvatomorphism, with the prototype compound Ph₃PAu[SC(OMe)=NPh (Hall et al., 1993) being also found in a chloroform solvate (Kuan et al., 2008). The common feature of all four molecules is the presence of intramolecular Au⋯O interactions. Very recently, a polymorph of Ph₃PAu[SC(OEt)=NPh has been reported (Yeo et al., 2016 ) in which there has been a dramatic conformational change compared with the previously described form (Hall & Tiekink, 1993 ). While the latter features the normally observed Au⋯O interaction, the new form features intramolecular Au⋯π (Caracelli et al., 2013 ) interactions. It was suggested that the crystallization conditions determined the conformation with that featuring the Au⋯π interactions being the thermodynamic outcome (Yeo et al., 2015 , 2016).

6. Synthesis and crystallization

IR spectra were obtained on a Perkin–Elmer Spectrum 400 FT Mid-IR/Far-IR spectrophotometer from 4000 to 400 cm⁻¹; abbreviation: s, strong. The ¹H NMR spectrum was recorded in CDCl₃ on a Bruker Avance 400 MHz NMR spectrometer with chemical shifts relative to tetramethylsilane; abbreviations for NMR assignments: s, singlet; d, doublet; t, triplet; m, multiplet.

Preparation of (I): NaOH (Merck; 0.20 mmol, 0.008 g) in MeOH (Merck; 1 ml) was added to a suspension of Ph₃PAuCl (0.20 mmol, 0.100 g) in MeOH (Merck; 10 ml), followed by addition of the thiocarbamide, MeOC(=S)N(H)(o-tol) (0.20 mmol, 0.036 g), prepared following literature precedents (Ho et al., 2005 ), in MeOH (10 ml). The resulting mixture was stirred for 2 h at 323 K. The solution was left for slow evaporation at room temperature, yielding colourless blocks after 2 weeks. Yield: 0.109 g (85%). M.p. 389–391 K.

IR (cm⁻¹): 1435 (s) (C=N), 1132 (s) (C—O), 1100 (s) (C—S). ¹H NMR (400 MHz, CDCl₃, 298 K): δ 7.53–7.39 (m, br, 15H, Ph₃P), 6.86 (d, 1H, o-tol-H4, J = 6.24 Hz), 6.85 (t, 1H, o-tol-H3, J = 6.16 Hz), 6.73 (d, 1H, o-tol-H1, J = 7.70 Hz), 6.54 (t, 1H, o-tol-H2, J = 7.16 Hz), 3.93 (s, 3H, OMe), 2.11 (s, 3H, o-tol-Me) p.p.m.

7. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 4. The carbon-bound H atoms were placed in calculated positions (C—H = 0.95–0.98 Å) and were included in the refinement in the riding-model approximation, with U_iso(H) set to 1.2–1.5U_equiv(C). Owing to poor agreement, a number of reflections, i.e. (0 $[\overline{11}]$ 4), (9 $[\overline{11}]$ 5), ( $[\overline{3}]$ 3 12), ( $[\overline{3}]$ $[\overline{13}]$ 7), ( $[\overline{10}]$ 11 2), ( $[\overline{6}]$ 10 1), ( $[\overline{5}]$ $[\overline{8}]$ 4), (7 $[\overline{8}]$ 6), ( $[\overline{6}]$ $[\overline{10}]$ 9), (4 $[\overline{14}]$ 2), ( $[\overline{5}]$ $[\overline{5}]$ 14), ( $[\overline{9}]$ $[\overline{2}]$ 15), (6 $[\overline{7}]$ 7) and (5 8 5), were omitted from the final cycles of refinement. The maximum and minimum residual electron density peaks of 0.97 and 1.14 e Å⁻³, respectively, were located 0.80 and 0.85 Å from the Au atom.

Table 4
Experimental details

Crystal data
Chemical formula	[Au(C₉H₁₀NOS)(C₁₈H₁₅P)]
M_r	639.47
Crystal system, space group	Triclinic, P $[\overline{1}]$
Temperature (K)	100
a, b, c (Å)	9.3884 (8), 10.0610 (8), 13.3572 (11)
α, β, γ (°)	96.194 (1), 102.487 (1), 99.443 (1)
V (Å³)	1201.60 (17)
Z	2
Radiation type	Mo Kα
μ (mm⁻¹)	6.30
Crystal size (mm)	0.30 × 0.11 × 0.09

Data collection
Diffractometer	Bruker SMART APEX CCD
Absorption correction	Multi-scan (SADABS; Sheldrick, 1996 )
T_min, T_max	0.368, 0.746
No. of measured, independent and observed [I > 2σ(I)] reflections	18394, 7189, 6714
R_int	0.031
(sin θ/λ)_max (Å⁻¹)	0.716

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.023, 0.055, 1.04
No. of reflections	7189
No. of parameters	291
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.97, −1.14
Computer programs: SMART and SAINT (Bruker, 2007 ), SHELXS97 (Sheldrick, 2008 ), SHELXL2014/7 (Sheldrick, 2015 ), ORTEP-3 for Windows (Farrugia, 2012 ), QMol (Gans & Shalloway, 2001 ), DIAMOND (Brandenburg, 2006 ) and publCIF (Westrip, 2010 ).

Supporting information

CCDC reference: 1503822

Crystal structure: contains datablocks I, global. DOI: https://doi.org/10.1107/S2056989016014419/hb7616sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989016014419/hb7616Isup2.hkl

checkCIF report

Computing details top

Data collection: SMART (Bruker, 2007); cell refinement: SMART (Bruker, 2007); data reduction: SAINT (Bruker, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014/7 (Sheldrick, 2015); molecular graphics: ORTEP-3 for Windows (Farrugia, 2012), QMol (Gans & Shalloway, 2001), DIAMOND (Brandenburg, 2006); software used to prepare material for publication: publCIF (Westrip, 2010).

[(Z)-O-Methyl-N-(2-methylphenyl)thiocarbamato-κS](triphenylphosphane-κP)gold(I) top

Crystal data top

[Au(C₉H₁₀NOS)(C₁₈H₁₅P)]	Z = 2
M_r = 639.47	F(000) = 624
Triclinic, P1	D_x = 1.767 Mg m⁻³
a = 9.3884 (8) Å	Mo Kα radiation, λ = 0.71073 Å
b = 10.0610 (8) Å	Cell parameters from 9945 reflections
c = 13.3572 (11) Å	θ = 2.3–30.6°
α = 96.194 (1)°	µ = 6.30 mm⁻¹
β = 102.487 (1)°	T = 100 K
γ = 99.443 (1)°	Block, colourless
V = 1201.60 (17) Å³	0.30 × 0.11 × 0.09 mm

Data collection top

Bruker SMART APEX CCD diffractometer	7189 independent reflections
Radiation source: fine-focus sealed tube	6714 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.031
φ and ω scans	θ_max = 30.6°, θ_min = 1.6°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −13→13
T_min = 0.368, T_max = 0.746	k = −14→14
18394 measured reflections	l = −18→19

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F² > 2σ(F²)] = 0.023	H-atom parameters constrained
wR(F²) = 0.055	w = 1/[σ²(F_o²) + (0.0186P)² + 1.2573P] where P = (F_o² + 2F_c²)/3
S = 1.04	(Δ/σ)_max = 0.002
7189 reflections	Δρ_max = 0.97 e Å⁻³
291 parameters	Δρ_min = −1.14 e Å⁻³

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
Au	0.62037 (2)	0.84221 (2)	0.31176 (2)	0.01464 (3)
S1	0.47523 (7)	0.98235 (6)	0.23056 (5)	0.01606 (12)
P1	0.76792 (7)	0.70692 (7)	0.38621 (5)	0.01288 (12)
O1	0.3113 (2)	0.73724 (19)	0.17215 (15)	0.0192 (4)
N1	0.2275 (3)	0.8941 (2)	0.07556 (17)	0.0173 (4)
C1	0.3230 (3)	0.8657 (3)	0.1480 (2)	0.0155 (5)
C2	0.2349 (3)	1.0288 (3)	0.05179 (19)	0.0142 (5)
C3	0.1468 (3)	1.1117 (3)	0.09059 (19)	0.0146 (5)
C4	0.1448 (3)	1.2394 (3)	0.0581 (2)	0.0171 (5)
H4	0.0852	1.2966	0.0834	0.020*
C5	0.2279 (3)	1.2843 (3)	−0.0102 (2)	0.0189 (5)
H5	0.2256	1.3714	−0.0312	0.023*
C6	0.3149 (3)	1.2004 (3)	−0.0478 (2)	0.0185 (5)
H6	0.3728	1.2305	−0.0941	0.022*
C7	0.3170 (3)	1.0733 (3)	−0.0176 (2)	0.0171 (5)
H7	0.3751	1.0159	−0.0444	0.021*
C8	0.0546 (3)	1.0623 (3)	0.1631 (2)	0.0197 (5)
H8A	−0.0207	1.1186	0.1661	0.030*
H8B	0.1189	1.0691	0.2325	0.030*
H8C	0.0055	0.9672	0.1379	0.030*
C9	0.1757 (3)	0.6439 (3)	0.1169 (2)	0.0254 (6)
H9A	0.1726	0.5565	0.1432	0.038*
H9B	0.1731	0.6299	0.0427	0.038*
H9C	0.0897	0.6822	0.1275	0.038*
C10	0.7737 (3)	0.5607 (3)	0.29563 (19)	0.0141 (4)
C11	0.8969 (3)	0.4975 (3)	0.3086 (2)	0.0188 (5)
H11	0.9803	0.5322	0.3650	0.023*
C12	0.8984 (4)	0.3844 (3)	0.2396 (2)	0.0227 (6)
H12	0.9836	0.3435	0.2477	0.027*
C13	0.7749 (4)	0.3316 (3)	0.1588 (2)	0.0248 (6)
H13	0.7743	0.2522	0.1131	0.030*
C14	0.6526 (4)	0.3940 (3)	0.1447 (2)	0.0274 (6)
H14	0.5689	0.3581	0.0887	0.033*
C15	0.6521 (3)	0.5091 (3)	0.2123 (2)	0.0202 (5)
H15	0.5687	0.5527	0.2016	0.024*
C16	0.9625 (3)	0.7857 (2)	0.4343 (2)	0.0157 (5)
C17	1.0410 (3)	0.7831 (3)	0.5353 (2)	0.0185 (5)
H17	0.9900	0.7481	0.5839	0.022*
C18	1.1938 (3)	0.8315 (3)	0.5651 (2)	0.0211 (5)
H18	1.2467	0.8307	0.6342	0.025*
C19	1.2689 (3)	0.8808 (3)	0.4942 (2)	0.0217 (5)
H19	1.3737	0.9109	0.5140	0.026*
C20	1.1911 (3)	0.8863 (3)	0.3940 (2)	0.0232 (6)
H20	1.2426	0.9221	0.3459	0.028*
C21	1.0389 (3)	0.8399 (3)	0.3643 (2)	0.0200 (5)
H21	0.9860	0.8447	0.2961	0.024*
C22	0.7133 (3)	0.6418 (3)	0.49658 (19)	0.0146 (5)
C23	0.6720 (3)	0.7323 (3)	0.5671 (2)	0.0180 (5)
H23	0.6636	0.8215	0.5527	0.022*
C24	0.6434 (3)	0.6919 (3)	0.6579 (2)	0.0203 (5)
H24	0.6175	0.7540	0.7066	0.024*
C25	0.6526 (3)	0.5605 (3)	0.6777 (2)	0.0218 (5)
H25	0.6333	0.5331	0.7401	0.026*
C26	0.6895 (3)	0.4696 (3)	0.6072 (2)	0.0211 (5)
H26	0.6939	0.3795	0.6209	0.025*
C27	0.7205 (3)	0.5091 (3)	0.5160 (2)	0.0166 (5)
H27	0.7461	0.4465	0.4676	0.020*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Au	0.01482 (5)	0.01725 (5)	0.01246 (5)	0.00688 (3)	0.00122 (3)	0.00319 (3)
S1	0.0148 (3)	0.0158 (3)	0.0163 (3)	0.0049 (2)	−0.0005 (2)	0.0021 (2)
P1	0.0130 (3)	0.0143 (3)	0.0110 (3)	0.0041 (2)	0.0010 (2)	0.0018 (2)
O1	0.0209 (10)	0.0144 (9)	0.0202 (9)	0.0052 (7)	−0.0014 (8)	0.0038 (7)
N1	0.0172 (11)	0.0163 (10)	0.0164 (10)	0.0045 (8)	−0.0009 (8)	0.0019 (8)
C1	0.0175 (12)	0.0149 (11)	0.0136 (11)	0.0054 (9)	0.0019 (9)	−0.0005 (9)
C2	0.0130 (11)	0.0151 (11)	0.0114 (10)	0.0026 (9)	−0.0029 (9)	0.0008 (9)
C3	0.0145 (11)	0.0173 (11)	0.0096 (10)	0.0018 (9)	−0.0002 (9)	−0.0004 (9)
C4	0.0205 (13)	0.0151 (11)	0.0153 (11)	0.0051 (10)	0.0027 (10)	0.0017 (9)
C5	0.0212 (13)	0.0167 (12)	0.0174 (12)	0.0006 (10)	0.0027 (10)	0.0046 (10)
C6	0.0173 (12)	0.0225 (13)	0.0159 (12)	0.0019 (10)	0.0051 (10)	0.0038 (10)
C7	0.0135 (11)	0.0202 (12)	0.0166 (12)	0.0048 (10)	0.0011 (9)	0.0006 (10)
C8	0.0215 (13)	0.0206 (12)	0.0159 (12)	0.0016 (10)	0.0040 (10)	0.0021 (10)
C9	0.0283 (15)	0.0145 (12)	0.0278 (15)	−0.0001 (11)	−0.0035 (12)	0.0067 (11)
C10	0.0150 (11)	0.0165 (11)	0.0110 (10)	0.0025 (9)	0.0036 (9)	0.0021 (9)
C11	0.0203 (13)	0.0209 (12)	0.0153 (12)	0.0076 (10)	0.0029 (10)	0.0005 (10)
C12	0.0295 (15)	0.0221 (13)	0.0215 (13)	0.0125 (12)	0.0106 (12)	0.0045 (11)
C13	0.0360 (17)	0.0183 (13)	0.0184 (13)	0.0025 (12)	0.0077 (12)	−0.0037 (10)
C14	0.0290 (16)	0.0279 (15)	0.0175 (13)	−0.0040 (12)	0.0000 (12)	−0.0049 (11)
C15	0.0139 (12)	0.0267 (14)	0.0183 (12)	0.0014 (10)	0.0026 (10)	0.0026 (10)
C16	0.0189 (12)	0.0112 (10)	0.0151 (11)	0.0038 (9)	0.0003 (10)	−0.0004 (9)
C17	0.0174 (12)	0.0191 (12)	0.0173 (12)	0.0018 (10)	0.0020 (10)	0.0027 (10)
C18	0.0157 (12)	0.0208 (13)	0.0214 (13)	−0.0006 (10)	−0.0036 (10)	0.0022 (10)
C19	0.0147 (12)	0.0192 (12)	0.0276 (14)	−0.0016 (10)	0.0039 (11)	−0.0027 (11)
C20	0.0238 (14)	0.0206 (13)	0.0256 (14)	−0.0014 (11)	0.0123 (12)	0.0016 (11)
C21	0.0216 (13)	0.0194 (12)	0.0183 (12)	0.0037 (10)	0.0030 (10)	0.0038 (10)
C22	0.0140 (11)	0.0157 (11)	0.0135 (11)	0.0029 (9)	0.0021 (9)	0.0014 (9)
C23	0.0178 (12)	0.0174 (12)	0.0174 (12)	0.0031 (10)	0.0026 (10)	−0.0005 (9)
C24	0.0187 (13)	0.0247 (13)	0.0160 (12)	0.0032 (11)	0.0041 (10)	−0.0014 (10)
C25	0.0176 (13)	0.0326 (15)	0.0160 (12)	0.0038 (11)	0.0051 (10)	0.0062 (11)
C26	0.0217 (13)	0.0199 (13)	0.0237 (14)	0.0038 (10)	0.0077 (11)	0.0066 (10)
C27	0.0167 (12)	0.0162 (11)	0.0166 (12)	0.0051 (9)	0.0025 (10)	0.0014 (9)

Geometric parameters (Å, º) top

Au—P1	2.2529 (6)	C11—H11	0.9500
Au—S1	2.3114 (6)	C12—C13	1.387 (4)
S1—C1	1.768 (3)	C12—H12	0.9500
P1—C16	1.812 (3)	C13—C14	1.384 (5)
P1—C22	1.814 (3)	C13—H13	0.9500
P1—C10	1.817 (3)	C14—C15	1.391 (4)
O1—C1	1.359 (3)	C14—H14	0.9500
O1—C9	1.449 (3)	C15—H15	0.9500
N1—C1	1.260 (3)	C16—C17	1.396 (4)
N1—C2	1.419 (3)	C16—C21	1.399 (4)
C2—C7	1.392 (4)	C17—C18	1.391 (4)
C2—C3	1.403 (4)	C17—H17	0.9500
C3—C4	1.402 (4)	C18—C19	1.383 (4)
C3—C8	1.503 (4)	C18—H18	0.9500
C4—C5	1.388 (4)	C19—C20	1.391 (4)
C4—H4	0.9500	C19—H19	0.9500
C5—C6	1.394 (4)	C20—C21	1.384 (4)
C5—H5	0.9500	C20—H20	0.9500
C6—C7	1.383 (4)	C21—H21	0.9500
C6—H6	0.9500	C22—C27	1.396 (4)
C7—H7	0.9500	C22—C23	1.398 (4)
C8—H8A	0.9800	C23—C24	1.386 (4)
C8—H8B	0.9800	C23—H23	0.9500
C8—H8C	0.9800	C24—C25	1.388 (4)
C9—H9A	0.9800	C24—H24	0.9500
C9—H9B	0.9800	C25—C26	1.379 (4)
C9—H9C	0.9800	C25—H25	0.9500
C10—C11	1.396 (4)	C26—C27	1.396 (4)
C10—C15	1.394 (4)	C26—H26	0.9500
C11—C12	1.389 (4)	C27—H27	0.9500

P1—Au—S1	177.61 (2)	C13—C12—C11	119.7 (3)
C1—S1—Au	103.14 (9)	C13—C12—H12	120.2
C16—P1—C22	104.74 (12)	C11—C12—H12	120.2
C16—P1—C10	102.91 (12)	C14—C13—C12	120.2 (3)
C22—P1—C10	107.07 (12)	C14—C13—H13	119.9
C16—P1—Au	115.26 (8)	C12—C13—H13	119.9
C22—P1—Au	113.63 (9)	C13—C14—C15	120.2 (3)
C10—P1—Au	112.28 (9)	C13—C14—H14	119.9
C1—O1—C9	114.9 (2)	C15—C14—H14	119.9
C1—N1—C2	121.4 (2)	C14—C15—C10	120.1 (3)
N1—C1—O1	120.7 (2)	C14—C15—H15	120.0
N1—C1—S1	125.9 (2)	C10—C15—H15	120.0
O1—C1—S1	113.38 (18)	C17—C16—C21	119.2 (3)
C7—C2—C3	120.2 (2)	C17—C16—P1	122.4 (2)
C7—C2—N1	120.3 (2)	C21—C16—P1	118.1 (2)
C3—C2—N1	119.2 (2)	C18—C17—C16	120.2 (3)
C4—C3—C2	118.3 (2)	C18—C17—H17	119.9
C4—C3—C8	121.4 (2)	C16—C17—H17	119.9
C2—C3—C8	120.4 (2)	C19—C18—C17	120.1 (3)
C5—C4—C3	121.5 (2)	C19—C18—H18	120.0
C5—C4—H4	119.3	C17—C18—H18	120.0
C3—C4—H4	119.3	C18—C19—C20	120.1 (3)
C4—C5—C6	119.3 (2)	C18—C19—H19	119.9
C4—C5—H5	120.3	C20—C19—H19	119.9
C6—C5—H5	120.3	C21—C20—C19	120.0 (3)
C7—C6—C5	120.1 (2)	C21—C20—H20	120.0
C7—C6—H6	120.0	C19—C20—H20	120.0
C5—C6—H6	120.0	C20—C21—C16	120.4 (3)
C6—C7—C2	120.6 (2)	C20—C21—H21	119.8
C6—C7—H7	119.7	C16—C21—H21	119.8
C2—C7—H7	119.7	C27—C22—C23	119.9 (2)
C3—C8—H8A	109.5	C27—C22—P1	122.34 (19)
C3—C8—H8B	109.5	C23—C22—P1	117.6 (2)
H8A—C8—H8B	109.5	C24—C23—C22	120.0 (3)
C3—C8—H8C	109.5	C24—C23—H23	120.0
H8A—C8—H8C	109.5	C22—C23—H23	120.0
H8B—C8—H8C	109.5	C25—C24—C23	119.9 (3)
O1—C9—H9A	109.5	C25—C24—H24	120.0
O1—C9—H9B	109.5	C23—C24—H24	120.0
H9A—C9—H9B	109.5	C26—C25—C24	120.4 (3)
O1—C9—H9C	109.5	C26—C25—H25	119.8
H9A—C9—H9C	109.5	C24—C25—H25	119.8
H9B—C9—H9C	109.5	C25—C26—C27	120.5 (3)
C11—C10—C15	119.2 (2)	C25—C26—H26	119.8
C11—C10—P1	121.3 (2)	C27—C26—H26	119.8
C15—C10—P1	119.5 (2)	C22—C27—C26	119.3 (2)
C12—C11—C10	120.6 (3)	C22—C27—H27	120.4
C12—C11—H11	119.7	C26—C27—H27	120.4
C10—C11—H11	119.7

C2—N1—C1—O1	177.6 (2)	C11—C10—C15—C14	1.7 (4)
C2—N1—C1—S1	0.8 (4)	P1—C10—C15—C14	−177.5 (2)
C9—O1—C1—N1	−6.4 (4)	C22—P1—C16—C17	2.7 (2)
C9—O1—C1—S1	170.9 (2)	C10—P1—C16—C17	−109.1 (2)
Au—S1—C1—N1	−167.2 (2)	Au—P1—C16—C17	128.3 (2)
Au—S1—C1—O1	15.8 (2)	C22—P1—C16—C21	176.7 (2)
C1—N1—C2—C7	88.2 (3)	C10—P1—C16—C21	64.9 (2)
C1—N1—C2—C3	−98.3 (3)	Au—P1—C16—C21	−57.6 (2)
C7—C2—C3—C4	−0.4 (4)	C21—C16—C17—C18	−1.2 (4)
N1—C2—C3—C4	−173.9 (2)	P1—C16—C17—C18	172.8 (2)
C7—C2—C3—C8	178.3 (2)	C16—C17—C18—C19	−0.9 (4)
N1—C2—C3—C8	4.7 (4)	C17—C18—C19—C20	2.2 (4)
C2—C3—C4—C5	−0.3 (4)	C18—C19—C20—C21	−1.4 (4)
C8—C3—C4—C5	−178.9 (2)	C19—C20—C21—C16	−0.7 (4)
C3—C4—C5—C6	0.3 (4)	C17—C16—C21—C20	2.0 (4)
C4—C5—C6—C7	0.5 (4)	P1—C16—C21—C20	−172.3 (2)
C5—C6—C7—C2	−1.2 (4)	C16—P1—C22—C27	−92.1 (2)
C3—C2—C7—C6	1.1 (4)	C10—P1—C22—C27	16.8 (3)
N1—C2—C7—C6	174.6 (2)	Au—P1—C22—C27	141.3 (2)
C16—P1—C10—C11	28.4 (2)	C16—P1—C22—C23	83.8 (2)
C22—P1—C10—C11	−81.7 (2)	C10—P1—C22—C23	−167.4 (2)
Au—P1—C10—C11	152.94 (19)	Au—P1—C22—C23	−42.8 (2)
C16—P1—C10—C15	−152.5 (2)	C27—C22—C23—C24	2.3 (4)
C22—P1—C10—C15	97.5 (2)	P1—C22—C23—C24	−173.7 (2)
Au—P1—C10—C15	−27.9 (2)	C22—C23—C24—C25	−1.4 (4)
C15—C10—C11—C12	−0.2 (4)	C23—C24—C25—C26	−0.2 (4)
P1—C10—C11—C12	178.9 (2)	C24—C25—C26—C27	1.0 (4)
C10—C11—C12—C13	−1.8 (4)	C23—C22—C27—C26	−1.5 (4)
C11—C12—C13—C14	2.3 (5)	P1—C22—C27—C26	174.3 (2)
C12—C13—C14—C15	−0.8 (5)	C25—C26—C27—C22	−0.1 (4)
C13—C14—C15—C10	−1.2 (4)

Hydrogen-bond geometry (Å, º) top

Cg1 and Cg2 are the centroids of the (C2–C7) and (C22–C27) rings, respectively.

D—H···A	D—H	H···A	D···A	D—H···A
C8—H8C···Cg1ⁱ	0.98	2.73	3.481 (3)	134
Cg2—–···Cg2ⁱⁱ	–	–	3.8033 (17)	–

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

Selected geometric data (Å, °) for (I) and (I·MeOH)^a top

Parameter	(I)	(I·MeOH)
Au—S1	2.3114 (6)	2.3009 (17)
Au—P1	2.2529 (6)	2.2558 (15)
C1—S1	1.768 (3)	1.751 (7)
C1—O1	1.359 (3)	1.356 (9)
C1—N1	1.260 (3)	1.260 (8)
Au···O1	3.040 (2)	3.093 (5)
S1—Au—P1	177.61 (2)	175.52 (6)
Au—S1—C1	103.14 (9)	105.0 (2)
C1—O1—C9	114.9 (2)	116.3 (5)
C1—N1—C2	121.4 (2)	121.2 (6)
S1—C1—O1	113.38 (18)	113.5 (4)
S1—C1—N1	125.9 (2)	126.0 (6)
O1—C1—N1	120.7 (2)	120.5 (6)

Note: (a) Kuan et al. (2008).

Physiochemical properties for (I), (I·MeOH), and I and MeOH in (I·MeOH) top

Parameter	(I)	(I·MeOH)
		I	MeOH
Volume, V (Å³)	590.16	637.63	591.04
Surface area, A (Å²)	514.76	543.39	512.10
A:V (Å^-1)	0.87	0.85	0.87
Globularity, G	0.661	0.659	0.665
Asphericity, Ω	0.159	0.100	0.138
Density (g cm^-1)	1.767	1.658	–
Packing index (%)	68.2	67.3	–

Acknowledgements

Intensity data were provided by the University of Malaya Crystallographic Laboratory.

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