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The title compound, C12H8N2O6S2, (I), is a positional isomer of S-(2-nitro­phen­yl) 2-nitro­benzene­thio­sulfonate [Glidewell, Low & Wardell (2000). Acta Cryst. B56, 893–905], (II). The most obvious difference between the two isomers is the rotation of the nitro groups with respect to the planes of the adjacent aryl rings. In (I), the nitro groups are only slightly rotated out of the plane of the adjacent aryl ring [2.4 (6) and 6.7 (7)°], while in (II) the nitro groups are rotated by between 37 and 52°, in every case associated with S—S—C—C torsion angles close to 90°. Other important differences between the isomers are the C—S—S(O2)—C torsion angle [78.39 (2)° for (I) and 69.8 (3)° for (II) (mean)] and the dihedral angles between the aromatic rings [12.3 (3)° for (I) and 28.6 (3)° for (II) (mean)]. There are two types of C—H...O hydrogen bond in the structure [C...O = 3.262 (7) Å and C—H...O = 144°; C...O = 3.447 (7) Å and C—H...O = 166°] and these link the mol­ecules into a two-dimensional framework. The hydrogen-bond-acceptor properties differ between the two isomers.

Supporting information

cif

Crystallographic Information File (CIF) https://doi.org/10.1107/S0108270110027678/eg3053sup1.cif
Contains datablocks I, global

hkl

Structure factor file (CIF format) https://doi.org/10.1107/S0108270110027678/eg3053Isup2.hkl
Contains datablock I

CCDC reference: 796079

Comment top

This paper forms part of our continuing study of the synthesis and structural characterization of divalent sulfur compounds (Brito et al., 2008, and references therein). The title compound, (I), was isolated during attempts to synthesize sulfenamides by a condensation reaction between 4-nitrobenzenesulfenyl chloride, (III), and secondary amines. Compound (III) was purchased from Aldrich (purity 95%, CAS No. 937–32-6). Impurities were not identified in the technical information accompanying the compound, but we believe that (I) was probably an impurity in the commercial sample of (III). To our knowledge, compound (I) is not commercially available. We report here the structure of (I), 4-O2NC6H4SSO2C6H4O2N-4.

The molecular structure of (I) is shown in Fig. 1 and selected geometric parameters are given in Table 1. Compound (I) is a positional isomer of S-(2-nitrophenyl) 2-nitrobenzenethiosulfonate, (II), which crystallizes with Z = 3 and S—S bond distances in the range 2.070 (2)–2.076 (2) Å (Glidewell et al., 2000). The two isomers exhibit important differences with respect to bonding geometries and conformation. The S—S bond distance in (I) is somewhat longer than that in (II). The S—S distances vary upon oxidation of the S centers in the order S—S < SO2—S (Aucott et al., 2005). A survey of C—S—S—C fragments (Allen et al., 1987) found that S—S bond distances are bimodally distributed: for torsion angles in the ranges 75–105 and 0–20°, the mean S—S bond distances are 2.031 (15) and 2.070 (22) Å, respectively.

The nitro groups are rotated by 6.7 (7)° and 2.4 (6)° in (I), while in (II) the nitro groups are rotated by between 37 and 52°, in every case associated with S—S—C—C torsion angles close to 90°, and at the same time the SO2C6H4O2N group is also displaced from the C6S plane. In general this conformation is observed where there are intermolecular C—H···O hydrogen bonds in the crystal structure, although this is not a sufficient condition for the occurrence of the twisted conformer (Aupers et al., 1999; Kucsman et al., 1984; Low, Storey et al., 2000). Other important differences between the isomers are the C—S—S(O2)—C torsion angle [78.39 (2)° for (I) and 69.8 (3)° for (II) (mean)] and the torsion angles between the aromatic rings [12.3 (3)° for (I) and 28.6 (3)° for (II) (mean)].

The molecules in (I) are linked into a continuous two-dimensional framework by means of C—H···O hydrogen bonds. The C—H···O(S) hydrogen bonds connect the molecules to form chains running along the diagonal between the a and b axes. Pairs of these chains, which are perpendicular to each other, are further connected by C—H···O hydrogen bonds (Table 2 and Fig. 2).

The aromatic C—H bonds betweeen the nitro and sulfone groups (C13—H13 and C15—H15) are expected to be the most acidic bonds in the molecule and thus to show the highest propensity for C—H···O hydrogen bond formation. Each molecule in (I) acts as a twofold donor at (x, y, z) and as a twofold acceptor; sulfone atom O15 acts as a single acceptor and nitro group atom O11 as an acceptor of hydrogen bond at (-x + 2, y - 1/2, -z + 1/2) and (x - 1, y + 1, z), respectively, while in (II) both of the sulfone O atoms acts as hydrogen-bond acceptors. The nitro group O atoms of the S-(4-nitrophenyl) fragment are not involved. The hydrogen-bond acceptor properties differ between the isomers.

The molecular conformation of (I) can be described by four independent torsion angles. The S—S—C—C angles are all close to 90° (Fig. 1 and Table 1), so that the projection of the S—S bond is approximately normal to the aryl ring. The conformation about the central S—S bond in (I) has one of the S—O bonds antiperiplanar to the remote aryl ring C1–C6. This same conformation is observed in (II) and is that usually observed in S-aryl arenethiosulfonates, ArSSO2Ar' (Caputo et al., 1984; Ferguson et al., 2000; Low, Glidewell & Wardell, 2000) in preference to the alternative conformation having the two aryl groups antiperiplanar rather than synclinal. The S—SO2 distance is somewhat larger than that in (II) [2.095 (2) Å for (I) and 2.073 (2) Å (mean) for (II)] and is characteristic in esters of this type.

A search in the Cambridge Structural Database (CSD; Version 5.31; Allen 2002) for phenylthiolates fragment C6H5-ySX (X = SO2C6H5-y; y = 0, 1) yielded seven structures: benzenethiosulfonic acid phenyl ester (CSD refcode BILCII10; Caputo et al., 1984), S-(p-tolyl) p-toluenethiosulfonate (refcode BILCOO01; Ferguson et al., 2000), p-tolylthiosulfonic acid p-tolyl ester (refcode BILCOO10; Caputo et al., 1984), di(p-bromophenyl)thiosulfonate (refcode BPTSLF; Noordik & Vos, 1967), S-(2-nitrophenyl) 2-nitrobenzene thiosulfonate (refcode FUQMIN; Glidewell et al., 2000), S-(2-nitrophenyl) p-toluenethiosulfonate (refcode LIYQOZ; Low, Glidewell &Wardell, 2000) and bis[2-(N,N-dipropylcarbamoyl)phenyl]thiosulfinate (refcode NAJBIJ; Kim et al., 1996), with an average S—SO2 distance of 2.087 (4) Å (restraint used in the search: only three-dimensional coordinates available; no private communication; only one sulfone group and no cyclic disulfide). The O—S—O angle is much larger than the ideal tetrahedral values, doubtless as a consequence of the substantial negative charge on the paired O atoms (Table 2), which is observed also in (II) as well as in the seven compound found in the search of the CSD described above.

Related literature top

For related literature, see: Allen (2002); Allen et al. (1987); Aucott et al. (2005); Aupers et al. (1999); Brito et al. (2008); Caputo et al. (1984); Ferguson et al. (2000); Glidewell et al. (2000); Kim et al. (1996); Kucsman et al. (1984); Low, Glidewell & Wardell (2000); Low, Storey, McCarron, Wardell, Ferguson & Glidewell (2000); Noordik & Vos (1967).

Experimental top

All reactions were carried out under an atmosphere of purified nitrogen. Solvents were dried and distilled prior to use. Equimolar quantities of 4-nitrobenzenesulfenyl chloride (0.01 mol) and secondary amines [please specify exact compounds] (0.01 mol) in dichloromethane solution were reacted in the presence of an excess of triethylamine. Crystals suitable for X-ray analysis were grown by slow evaporation from dichloromethane at room temperature. The spectroscopic properties of (I) were not determined because of the small amount of sample available.

Refinement top

All H atoms could be located by difference Fourier synthesis but were ultimately placed in calculated positions and treated using a riding model with C—H distances of 0.95 Å and fixed individual displacement parameters [Uiso(H) = 1.2Ueq(C)]. The absolute structure was determined on the basis of 950 measured Bijvoet pairs (coverage 99%). Since the molecules is achiral, the directions of the polar axes had been determined. Two reflections were not included in the data set as they were either partially obscured by the beam stop or were eliminated during data reduction.

Computing details top

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, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: XP in SHELXTL-Plus (Release 4.1; Sheldrick, 2008); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures top
[Figure 1] Fig. 1. Displacement ellipsoid plot of (I) with the atom-numbering scheme, showing 50% probability ellipsoids.
[Figure 2] Fig. 2. The C—H···O(S) hydrogen bonds connect the molecules to form chains running along the diagonal between the a and b axes. Pairs of these chains, which are perpendicular to each other, are further connected by C—H···O hydrogen bonds.
S-(4-Nitrophenyl) 4-nitrobenzenethiosulfonate top
Crystal data top
C12H8N2O6S2F(000) = 696
Mr = 340.32Dx = 1.687 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 4988 reflections
a = 5.2585 (7) Åθ = 2.0–25.7°
b = 6.0483 (5) ŵ = 0.43 mm1
c = 42.133 (4) ÅT = 173 K
V = 1340.0 (2) Å3Needle, colourless
Z = 40.32 × 0.12 × 0.12 mm
Data collection top
Stoe IPDS II two-circle
diffractometer
2453 independent reflections
Radiation source: fine-focus sealed tube1791 reflections with I > 2σ(I)
Graphite monochromatorRint = 0.096
ω scansθmax = 25.3°, θmin = 1.9°
Absorption correction: multi-scan
(MULABS; Spek, 2009; Blessing, 1995)
h = 56
Tmin = 0.875, Tmax = 0.950k = 67
5902 measured reflectionsl = 5050
Refinement top
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.064H-atom parameters constrained
wR(F2) = 0.157 w = 1/[σ2(Fo2) + (0.0908P)2]
where P = (Fo2 + 2Fc2)/3
S = 0.97(Δ/σ)max < 0.001
2453 reflectionsΔρmax = 0.67 e Å3
199 parametersΔρmin = 0.37 e Å3
0 restraintsAbsolute structure: Flack (1983)
Primary atom site location: structure-invariant direct methodsAbsolute structure parameter: 0.06 (18)
Crystal data top
C12H8N2O6S2V = 1340.0 (2) Å3
Mr = 340.32Z = 4
Orthorhombic, P212121Mo Kα radiation
a = 5.2585 (7) ŵ = 0.43 mm1
b = 6.0483 (5) ÅT = 173 K
c = 42.133 (4) Å0.32 × 0.12 × 0.12 mm
Data collection top
Stoe IPDS II two-circle
diffractometer
2453 independent reflections
Absorption correction: multi-scan
(MULABS; Spek, 2009; Blessing, 1995)
1791 reflections with I > 2σ(I)
Tmin = 0.875, Tmax = 0.950Rint = 0.096
5902 measured reflections
Refinement top
R[F2 > 2σ(F2)] = 0.064H-atom parameters constrained
wR(F2) = 0.157Δρmax = 0.67 e Å3
S = 0.97Δρmin = 0.37 e Å3
2453 reflectionsAbsolute structure: Flack (1983)
199 parametersAbsolute structure parameter: 0.06 (18)
0 restraints
Special details top

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 (Å2) top
xyzUiso*/Ueq
S10.7532 (3)0.1284 (2)0.13848 (3)0.0430 (4)
O1S0.5146 (9)0.0560 (6)0.12587 (9)0.0512 (10)
O2S0.9251 (9)0.0251 (7)0.15338 (9)0.0549 (11)
S20.9680 (3)0.2585 (3)0.10100 (3)0.0449 (4)
C10.7159 (10)0.3891 (10)0.07893 (11)0.0376 (12)
C20.6414 (12)0.5995 (10)0.08645 (12)0.0431 (13)
H20.72720.67960.10260.052*
C30.4394 (12)0.6950 (9)0.07026 (12)0.0425 (13)
H30.37740.83680.07610.051*
C40.3307 (10)0.5800 (9)0.04553 (11)0.0382 (12)
C50.4087 (10)0.3732 (10)0.03674 (11)0.0392 (12)
H50.32960.29890.01950.047*
C60.6064 (11)0.2733 (10)0.05350 (11)0.0411 (13)
H60.66560.13020.04780.049*
N10.1166 (10)0.6836 (8)0.02834 (10)0.0431 (12)
O10.0541 (9)0.8705 (8)0.03555 (9)0.0526 (10)
O20.0128 (9)0.5764 (7)0.00718 (9)0.0527 (10)
C110.6907 (11)0.3493 (10)0.16476 (12)0.0408 (13)
C120.8576 (11)0.3951 (11)0.18970 (12)0.0450 (14)
H121.00100.30290.19330.054*
C130.8134 (11)0.5734 (12)0.20894 (12)0.0482 (16)
H130.92520.60560.22600.058*
C140.6055 (11)0.7053 (9)0.20322 (12)0.0408 (13)
C150.4340 (11)0.6621 (10)0.17876 (12)0.0417 (13)
H150.29000.75420.17550.050*
C160.4780 (12)0.4828 (10)0.15942 (12)0.0434 (13)
H160.36450.45000.14250.052*
N110.5632 (11)0.9037 (9)0.22251 (11)0.0519 (13)
O110.7262 (10)0.9562 (8)0.24196 (10)0.0657 (13)
O120.3680 (11)1.0082 (9)0.21853 (11)0.0722 (15)
Atomic displacement parameters (Å2) top
U11U22U33U12U13U23
S10.0489 (8)0.0347 (7)0.0454 (6)0.0011 (7)0.0022 (7)0.0023 (6)
O1S0.048 (2)0.043 (2)0.062 (2)0.006 (2)0.003 (2)0.0001 (18)
O2S0.059 (3)0.046 (2)0.060 (2)0.007 (2)0.000 (2)0.009 (2)
S20.0474 (8)0.0457 (8)0.0417 (6)0.0006 (8)0.0031 (6)0.0029 (6)
C10.036 (3)0.037 (3)0.039 (2)0.001 (3)0.002 (2)0.003 (2)
C20.059 (4)0.031 (3)0.039 (2)0.006 (3)0.003 (2)0.004 (2)
C30.057 (4)0.028 (3)0.042 (2)0.004 (3)0.005 (2)0.000 (2)
C40.043 (3)0.032 (3)0.039 (2)0.002 (2)0.000 (2)0.003 (2)
C50.044 (3)0.036 (3)0.038 (2)0.005 (3)0.003 (2)0.001 (2)
C60.053 (4)0.031 (3)0.039 (2)0.003 (3)0.002 (2)0.002 (2)
N10.046 (3)0.039 (3)0.044 (2)0.001 (2)0.003 (2)0.003 (2)
O10.052 (3)0.046 (2)0.059 (2)0.009 (2)0.001 (2)0.002 (2)
O20.049 (3)0.053 (3)0.056 (2)0.001 (2)0.007 (2)0.0013 (19)
C110.045 (3)0.035 (3)0.043 (3)0.002 (2)0.001 (2)0.009 (2)
C120.041 (3)0.053 (4)0.041 (3)0.006 (3)0.006 (2)0.012 (3)
C130.042 (3)0.066 (4)0.036 (2)0.010 (3)0.002 (2)0.003 (3)
C140.049 (3)0.036 (3)0.038 (2)0.009 (3)0.004 (2)0.001 (2)
C150.036 (3)0.041 (3)0.048 (3)0.001 (3)0.001 (2)0.004 (2)
C160.041 (3)0.046 (3)0.044 (2)0.005 (3)0.004 (2)0.002 (2)
N110.058 (3)0.052 (3)0.047 (2)0.009 (3)0.005 (2)0.002 (2)
O110.068 (3)0.070 (3)0.059 (2)0.008 (3)0.004 (2)0.017 (2)
O120.083 (4)0.070 (4)0.063 (3)0.026 (3)0.003 (3)0.019 (3)
Geometric parameters (Å, º) top
S1—O1S1.431 (5)N1—O11.216 (6)
S1—O2S1.440 (4)N1—O21.230 (6)
S1—C111.767 (6)C11—C121.397 (7)
S1—S22.095 (2)C11—C161.398 (8)
S2—C11.801 (5)C12—C131.369 (9)
C1—C21.369 (8)C12—H120.9500
C1—C61.404 (7)C13—C141.375 (8)
C2—C31.388 (8)C13—H130.9500
C2—H20.9500C14—C151.394 (7)
C3—C41.377 (7)C14—N111.466 (8)
C3—H30.9500C15—C161.376 (8)
C4—C51.367 (8)C15—H150.9500
C4—N11.478 (7)C16—H160.9500
C5—C61.395 (7)N11—O111.228 (7)
C5—H50.9500N11—O121.217 (7)
C6—H60.9500
O1S—S1—O2S121.0 (3)O1—N1—O2123.4 (5)
O1S—S1—C11107.5 (3)O1—N1—C4118.5 (5)
O2S—S1—C11109.4 (2)O2—N1—C4118.0 (5)
O1S—S1—S2107.92 (17)C12—C11—C16120.6 (6)
O2S—S1—S2103.46 (19)C12—C11—S1120.3 (5)
C11—S1—S2106.77 (19)C16—C11—S1119.0 (4)
C1—S2—S199.05 (18)C13—C12—C11119.7 (6)
C2—C1—C6121.5 (5)C13—C12—H12120.2
C2—C1—S2119.9 (4)C11—C12—H12120.2
C6—C1—S2118.5 (4)C12—C13—C14119.2 (5)
C1—C2—C3119.5 (5)C12—C13—H13120.4
C1—C2—H2120.3C14—C13—H13120.4
C3—C2—H2120.3C13—C14—C15122.4 (5)
C4—C3—C2118.6 (5)C13—C14—N11119.9 (5)
C4—C3—H3120.7C15—C14—N11117.7 (5)
C2—C3—H3120.7C16—C15—C14118.5 (6)
C5—C4—C3122.9 (5)C16—C15—H15120.8
C5—C4—N1118.9 (5)C14—C15—H15120.8
C3—C4—N1118.2 (5)C15—C16—C11119.6 (5)
C4—C5—C6118.9 (5)C15—C16—H16120.2
C4—C5—H5120.6C11—C16—H16120.2
C6—C5—H5120.6O12—N11—O11123.1 (6)
C5—C6—C1118.4 (5)O12—N11—C14118.5 (5)
C5—C6—H6120.8O11—N11—C14118.4 (6)
C1—C6—H6120.8
O1S—S1—S2—C136.9 (3)O2S—S1—C11—C1220.7 (5)
O2S—S1—S2—C1166.3 (3)S2—S1—C11—C1290.6 (4)
C11—S1—S2—C178.4 (3)O1S—S1—C11—C1628.8 (5)
S1—S2—C1—C286.1 (5)O2S—S1—C11—C16161.9 (4)
S1—S2—C1—C696.1 (4)S2—S1—C11—C1686.8 (4)
C6—C1—C2—C35.2 (8)C16—C11—C12—C130.5 (8)
S2—C1—C2—C3177.1 (4)S1—C11—C12—C13176.8 (4)
C1—C2—C3—C44.4 (8)C11—C12—C13—C140.3 (8)
C2—C3—C4—C51.7 (8)C12—C13—C14—C151.2 (8)
C2—C3—C4—N1179.7 (5)C12—C13—C14—N11176.7 (5)
C3—C4—C5—C60.2 (8)C13—C14—C15—C161.2 (8)
N1—C4—C5—C6178.4 (5)N11—C14—C15—C16176.8 (5)
C4—C5—C6—C10.5 (8)C14—C15—C16—C110.3 (8)
C2—C1—C6—C53.2 (8)C12—C11—C16—C150.5 (8)
S2—C1—C6—C5179.0 (4)S1—C11—C16—C15176.8 (4)
C5—C4—N1—O1177.4 (5)C13—C14—N11—O12174.6 (6)
C3—C4—N1—O13.9 (7)C15—C14—N11—O127.5 (8)
C5—C4—N1—O21.7 (7)C13—C14—N11—O115.3 (8)
C3—C4—N1—O2176.9 (5)C15—C14—N11—O11172.7 (5)
O1S—S1—C11—C12153.8 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13···O11i0.952.453.262 (7)144
C15—H15···O(2S)ii0.952.523.447 (7)166
Symmetry codes: (i) x+2, y1/2, z+1/2; (ii) x1, y+1, z.

Experimental details

Crystal data
Chemical formulaC12H8N2O6S2
Mr340.32
Crystal system, space groupOrthorhombic, P212121
Temperature (K)173
a, b, c (Å)5.2585 (7), 6.0483 (5), 42.133 (4)
V3)1340.0 (2)
Z4
Radiation typeMo Kα
µ (mm1)0.43
Crystal size (mm)0.32 × 0.12 × 0.12
Data collection
DiffractometerStoe IPDS II two-circle
diffractometer
Absorption correctionMulti-scan
(MULABS; Spek, 2009; Blessing, 1995)
Tmin, Tmax0.875, 0.950
No. of measured, independent and
observed [I > 2σ(I)] reflections
5902, 2453, 1791
Rint0.096
(sin θ/λ)max1)0.602
Refinement
R[F2 > 2σ(F2)], wR(F2), S 0.064, 0.157, 0.97
No. of reflections2453
No. of parameters199
H-atom treatmentH-atom parameters constrained
Δρmax, Δρmin (e Å3)0.67, 0.37
Absolute structureFlack (1983)
Absolute structure parameter0.06 (18)

Computer programs: X-AREA (Stoe & Cie, 2001), SHELXS97 (Sheldrick, 2008), SHELXL97 (Sheldrick, 2008), XP in SHELXTL-Plus (Release 4.1; Sheldrick, 2008).

Selected geometric parameters (Å, º) top
S1—O1S1.431 (5)N1—O11.216 (6)
S1—O2S1.440 (4)N1—O21.230 (6)
S1—C111.767 (6)C14—N111.466 (8)
S1—S22.095 (2)N11—O111.228 (7)
S2—C11.801 (5)N11—O121.217 (7)
C4—N11.478 (7)
O1S—S1—O2S121.0 (3)O1—N1—O2123.4 (5)
O1S—S1—C11107.5 (3)O1—N1—C4118.5 (5)
O2S—S1—C11109.4 (2)O2—N1—C4118.0 (5)
O1S—S1—S2107.92 (17)O12—N11—O11123.1 (6)
O2S—S1—S2103.46 (19)O12—N11—C14118.5 (5)
C11—S1—S2106.77 (19)O11—N11—C14118.4 (6)
C1—S2—S199.05 (18)
S1—S2—C1—C286.1 (5)S2—S1—C11—C1290.6 (4)
S1—S2—C1—C696.1 (4)S2—S1—C11—C1686.8 (4)
Hydrogen-bond geometry (Å, º) top
D—H···AD—HH···AD···AD—H···A
C13—H13···O11i0.952.453.262 (7)144
C15—H15···O(2S)ii0.952.523.447 (7)166
Symmetry codes: (i) x+2, y1/2, z+1/2; (ii) x1, y+1, z.
 

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