(2E)-1-(2,4-Dichloro­phen­yl)-3-[4-(di­ethyl­amino)-2-hydroxy­phen­yl]prop-2-en-1-one

In the title mol­ecule, C₁₉H₁₉Cl₂NO₂, the angle between the mean planes of the 2,4-dichloro­phenyl and 2-hydroxy­phenyl groups is 81.8 (2)°. The ketone oxygen of the prop-2-en-1-one group is twisted in a synclinal conformation with the 2,4-dichloro­phenyl group [torsion angle = −75.7 (2)°]. The two diethyl extensions from the 4-(diethyl­amino)-2-hydroxy­phenyl group are twisted in anti- and syn-periplanar conformations. Crystal packing is stabilized by inter­molecular C—H...O hydrogen bonding between the ketone O atom from the prop-2-en-1-one group and H atoms from both the 2-hydroxy­phenyl ring and the hydr­oxy group; these hydrogen bonds link the mol­ecules into chains along the diagonal of the bc face of the unit cell. The 2-hydroxy­phenyl rings are stacked obliquely parallel to the ab face while the 2,4-dichloro­phenyl rings are stacked obliquely parallel to the bc face of the unit cell, each in an inverted conformation. Additional inter­molecular packing inter­actions occur between π orbitals of the 4-hydroxy­phenyl ring and an H atom from a nearby 2,4-dichloro­phenyl ring.

Key indicators

• Single-crystal X-ray study
• T = 296 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.046
• wR factor = 0.149
• Data-to-parameter ratio = 28.7

checkCIF/PLATON results

No syntax errors found



Alert level B
PLAT026_ALERT_3_B Ratio Observed / Unique Reflections too Low ....         31 Perc.
PLAT201_ALERT_2_B Isotropic non-H Atoms in Main Residue(s) .......          2
PLAT230_ALERT_2_B Hirshfeld Test Diff for    N      -   C16     ..      24.22 su
PLAT230_ALERT_2_B Hirshfeld Test Diff for    C1     -   C2      ..       9.03 su

Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
            Tmin and Tmax reported:      0.721     1.000
            Tmin(prime) and Tmax expected:      0.825     0.925
            RR(prime) =      0.808
            Please check that your absorption correction is appropriate.
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.81
PLAT062_ALERT_4_C Rescale T(min) & T(max) by .....................       0.93
PLAT230_ALERT_2_C Hirshfeld Test Diff for    O2     -   C11     ..       6.64 su

Alert level G
ABSTM02_ALERT_3_G  When printed, the submitted absorption T values will be
            replaced by the scaled T values. Since the ratio of scaled T's
            is identical to the ratio of reported T values, the scaling
            does not imply a change to the absorption corrections used in
            the study.
            Ratio of Tmax expected/reported      0.925
            Tmax scaled      0.925 Tmin scaled      0.667

   0 ALERT level A = In general: serious problem
   4 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   1 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
   4 ALERT type 3 Indicator that the structure quality may be low
   1 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Chalcones are a class of naturally occurring compounds with various biological activities. They are known as the precursors of all flavonoid type natural products in biosynthesis. Chalcones can be easily obtained from the aldol condensation of aromatic aldehydes and aromatic ketones. This class of compounds presents interesting biological properties such as cytotoxicity (Pandey et al. 2005), antiherpes, and antitumour activity and may be useful for the chemotherapy of leishmaniasis among others (Lawrence et al. 2001). Chalcone derivatives are recognized for NLO properties and have good crystallization ability (Goto et al. 1991; Indira et al. 2002; Sarojini et al. 2006). Structures of few dichloro substituted chalcones viz., (2E)-1-(2,4-dichlorophenyl)-3-(quinolin-8-yl)prop-2-en-1-one (Sarojini et al. 2007), (2E)-1-(2,4-dichlorophenyl)-3-(4,5-dimethoxy-2-nitrophenyl) prop-2-en-1-one (Yathirajan et al. 2007a), (2E)-1-(2,4-dichlorophenyl)-3-(6-methoxy-2-naphthyl)prop-2-en-1-one (Yathirajan et al. 2007b), (2E)-1-(2,4-dichlorophenyl)-3-(2-hydroxy-3-methoxyphenyl) prop-2-en-1-one (Yathirajan et al. 2007c), (2E)-1-(2,4-dichlorophenyl)-3-(4-nitrophenyl)prop-2-en-1-one (Yathirajan et al. 2007 d), (2E)-1-(2,4-dichlorophenyl)-3-(2-hydroxyphenyl)prop-2-en-1-one (Yathirajan et al. 2007 e) have been published. In continuation of our work on chalcones, a new chalcone, (I), C₁₉H₁₉Cl₄O₂ has been synthesized and its crystal structure is reported.

The angle between the mean planes of the 2,4-dichlorolphenyl and 2-hydroxyphenyl groups is 81.8 (2)° (Fig. 1). The ketone oxygen of the prop-2-en-1-one group is twisted in a syn-clinal conformation with the 2,4-dichlorophenyl group [C2–C1–C7–O1 torsion angle = -75.7 (2)°]. The two diethyl extensions from the 4-(diethylamino)-2-hydroxyphenyl group are twisted in an anti- [C12–C13–N–C18 = -174.65 (17)°] and syn- [C2–C13—N–C16 = 3.3 (3)°] periplanar conformation. Crystal packing is stabilized by intermolecular C—H···O hydrogen bonding between the ketone oxygen (O1) from the prop-2-en-1-one group and hydrogen atoms from both the 2-hydroxyl phenyl ring (H12A) and the hydroxyl group (H2A) which link the molecules into chains diagonal along the bc face of the unit cell (Fig. 2). The 2-hydroxypheny rings are stacked obliquely parallel to the ab face while the 2,4-dichlorolphenyl rings are stacked obliquely parallel to the bc face, respectively, of the unit cell, each in an inverted conformation. Additional intermolecular packing interactions occur between Cg2-π orbitals of the 4-hydroxyphenyl ring and H6A from a nearby 2,4-dichlorolphenyl ring. [Cg2 - center of gravity, C10–C15; C6–H6A···Cg(2) = 2.83 Å (1 - x, 1 - y, 1 - z)].

Related literature

For related structures, see: Sarojini et al. (2007); Yathirajan et al. (2007a,b,c,d,e). For related literature, see: Goto et al. (1991); Indira et al. (2002); Lawrence et al. (2001); Pandey et al. (2005); & Sarojini et al. (2006).

S2. Experimental

4-(Diethylamino)-2-hydroxybenzaldehyde (1.93 g, 0.01 mol) in ethanol (25 ml) was mixed with 1-(2,4-dichlorophenyl)ethanone (1.89 g, 0.01 mol) in ethanol (25 ml) and the mixture was treated with 10 ml of 10% KOH solution (Fig. 3). The reaction mixture was then kept for constant stirring. The solid precipitate obtained was filtered, washed with ethanol and dried. Crystal growth was carried out from a 1:1 mixture of acetone and toluene by the slow evaporation technique (m.p.: 427–429 K). Analysis found: C 62.58, H 5.22, N 3.18%; C₁₉H₁₉Cl₄O₂ requires: C 62.65, H 5.26, N 3.85%.

S3. Refinement

The hydroxyl atom (H2A) was located in a difference Fourier map and along with all other all other H atoms placed in their calculated positions were then refined using the riding model with O—H = 0.82 Å and C—H = 0.93 to 0.97 Å, and with U_iso(H) = 1.19–1.50U_eq(C, O).

Computing details

Data collection: CrysAlis PRO (Oxford Diffraction, 2007); cell refinement: CrysAlis PRO (Oxford Diffraction, 2007); data reduction: CrysAlis PRO (Oxford Diffraction, 2007); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2000); software used to prepare material for publication: SHELXTL (Sheldrick, 1997).

Figures

	Fig. 1. Molecular structure of the title compound, showing atom labeling and 50% probability displacement ellipsoids.
	Fig. 2. Packing diagram of the title compound, viewed down the b axis.
	Fig. 3. Synthetic scheme for C19H19Cl4O2.

(2E)-1-(2,4-Dichlorophenyl)-3-[4-(diethylamino)-2-hydroxyphenyl]prop-2-en-1-one

Crystal data

C19H19Cl2NO2	F(000) = 760
Mr = 364.25	Dx = 1.340 Mg m^−3
Monoclinic, P21/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 3455 reflections
a = 10.6129 (5) Å	θ = 4.6–32.5°
b = 13.9570 (7) Å	µ = 0.37 mm^−1
c = 12.6858 (6) Å	T = 296 K
β = 106.012 (5)°	Chunk, yellow
V = 1806.17 (15) Å^3	0.51 × 0.35 × 0.21 mm
Z = 4

Data collection

Oxford Diffraction Gemini R CCD diffractometer	6017 independent reflections
Radiation source: fine-focus sealed tube	1867 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.054
Detector resolution: 10.5081 pixels mm^-1	θmax = 32.5°, θmin = 4.6°
φ and ω scans	h = −15→13
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2007)	k = −20→12
Tmin = 0.721, Tmax = 1.000	l = −18→18
19547 measured reflections

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)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.149	H-atom parameters constrained
S = 0.83	w = 1/[σ^2(Fo^2) + (0.0576P)^2] where P = (Fo^2 + 2Fc^2)/3
6017 reflections	(Δ/σ)max < 0.001
210 parameters	Δρmax = 0.34 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
Cl1	0.45137 (6)	0.16227 (5)	0.89389 (6)	0.0833 (2)
Cl2	0.34504 (7)	−0.20410 (5)	0.78456 (5)	0.0877 (3)
O1	0.70872 (15)	0.19447 (12)	0.79693 (12)	0.0708 (5)
O2	1.01216 (14)	0.20094 (11)	1.15772 (12)	0.0671 (4)
H2A	1.0729	0.2332	1.1947	0.081*
N	1.15746 (18)	−0.00593 (14)	1.46912 (14)	0.0704 (6)
C1	0.62657 (19)	0.04520 (16)	0.83812 (14)	0.0521 (5)
C2	0.5016 (2)	0.05425 (16)	0.85143 (15)	0.0546 (5)
C3	0.4148 (2)	−0.02179 (16)	0.83333 (16)	0.0597 (6)
H3A	0.3315	−0.0143	0.8427	0.072*
C4	0.4530 (2)	−0.10837 (16)	0.80141 (16)	0.0600 (6)
C5	0.5745 (2)	−0.11972 (18)	0.78363 (17)	0.0681 (7)
H5A	0.5984	−0.1778	0.7589	0.082*
C6	0.6597 (2)	−0.04327 (18)	0.80330 (17)	0.0662 (7)
H6A	0.7425	−0.0511	0.7929	0.079*
C7	0.7233 (2)	0.12748 (16)	0.86219 (17)	0.0544 (5)
C8	0.8254 (2)	0.12713 (16)	0.96368 (16)	0.0563 (6)
H8A	0.8793	0.1807	0.9817	0.068*
C9	0.84670 (18)	0.05259 (16)	1.03407 (15)	0.0518 (5)
H9A	0.7955	−0.0010	1.0082	0.062*
C10	0.93474 (17)	0.04148 (15)	1.14228 (15)	0.0496 (5)
C11	1.01176 (18)	0.11466 (14)	1.20542 (16)	0.0469 (5)
C12	1.08461 (18)	0.09849 (15)	1.31272 (16)	0.0541 (5)
H12A	1.1324	0.1487	1.3528	0.065*
C13	1.08816 (19)	0.00860 (16)	1.36241 (16)	0.0563 (6)
C14	1.0175 (2)	−0.06473 (16)	1.29886 (18)	0.0608 (6)
H14A	1.0213	−0.1262	1.3279	0.073*
C15	0.94212 (19)	−0.04778 (16)	1.19390 (17)	0.0577 (5)
H15A	0.8934	−0.0982	1.1550	0.069*
C16	1.2275 (3)	0.0739 (2)	1.5403 (2)	0.0884 (8)
H16A	1.1798	0.1332	1.5188	0.106*
H16B	1.2302	0.0608	1.6160	0.106*
C17	1.3600 (3)	0.0848 (2)	1.5315 (3)	0.1107 (10)*
H17A	1.4006	0.1389	1.5743	0.166*
H17B	1.3577	0.0948	1.4561	0.166*
H17C	1.4094	0.0279	1.5582	0.166*
C18	1.1709 (3)	−0.10152 (18)	1.51721 (19)	0.0753 (7)
H18A	1.0860	−0.1328	1.4957	0.090*
H18B	1.1961	−0.0952	1.5964	0.090*
C19	1.2693 (3)	−0.1652 (2)	1.4854 (2)	0.0872 (8)*
H19A	1.2676	−0.2277	1.5165	0.131*
H19B	1.3554	−0.1382	1.5126	0.131*
H19C	1.2476	−0.1701	1.4070	0.131*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Cl1	0.0783 (4)	0.0719 (5)	0.1067 (5)	0.0181 (3)	0.0374 (4)	−0.0113 (4)
Cl2	0.0944 (5)	0.0696 (5)	0.0860 (5)	−0.0061 (3)	0.0031 (4)	0.0063 (3)
O1	0.0686 (10)	0.0764 (11)	0.0587 (9)	0.0064 (8)	0.0028 (7)	0.0122 (8)
O2	0.0614 (10)	0.0628 (10)	0.0622 (9)	−0.0036 (7)	−0.0081 (7)	0.0075 (8)
N	0.0764 (13)	0.0731 (14)	0.0481 (11)	−0.0049 (10)	−0.0053 (9)	0.0078 (9)
C1	0.0424 (11)	0.0711 (15)	0.0395 (10)	0.0132 (10)	0.0058 (8)	−0.0009 (10)
C2	0.0569 (13)	0.0585 (14)	0.0441 (11)	0.0119 (11)	0.0069 (9)	−0.0005 (9)
C3	0.0518 (12)	0.0699 (17)	0.0556 (13)	0.0125 (12)	0.0121 (10)	0.0092 (11)
C4	0.0647 (15)	0.0605 (15)	0.0459 (11)	0.0129 (11)	0.0001 (10)	0.0009 (10)
C5	0.0715 (17)	0.0655 (16)	0.0595 (14)	0.0177 (13)	0.0053 (11)	−0.0137 (11)
C6	0.0522 (13)	0.0813 (18)	0.0622 (14)	0.0261 (12)	0.0110 (11)	−0.0120 (12)
C7	0.0459 (12)	0.0675 (15)	0.0477 (12)	0.0085 (10)	0.0096 (9)	−0.0007 (11)
C8	0.0472 (12)	0.0684 (15)	0.0486 (12)	0.0012 (10)	0.0055 (9)	−0.0015 (10)
C9	0.0408 (11)	0.0612 (14)	0.0506 (12)	0.0021 (9)	0.0078 (9)	−0.0052 (10)
C10	0.0381 (10)	0.0568 (14)	0.0498 (12)	0.0081 (9)	0.0052 (9)	−0.0019 (10)
C11	0.0389 (10)	0.0479 (13)	0.0514 (11)	0.0088 (9)	0.0081 (9)	0.0030 (9)
C12	0.0459 (12)	0.0616 (15)	0.0497 (12)	0.0006 (10)	0.0048 (9)	−0.0018 (10)
C13	0.0492 (12)	0.0661 (15)	0.0487 (12)	0.0041 (10)	0.0054 (9)	0.0054 (10)
C14	0.0578 (13)	0.0545 (14)	0.0623 (13)	0.0012 (11)	0.0035 (11)	0.0120 (11)
C15	0.0489 (12)	0.0561 (14)	0.0624 (13)	0.0016 (10)	0.0059 (10)	−0.0007 (11)
C16	0.0817 (19)	0.108 (2)	0.0698 (16)	0.0169 (16)	0.0122 (14)	0.0233 (15)
C18	0.0792 (17)	0.0818 (19)	0.0589 (14)	0.0060 (13)	0.0091 (12)	0.0192 (12)

Geometric parameters (Å, º)

Cl1—C2	1.734 (2)	C9—H9A	0.9300
Cl2—C4	1.734 (2)	C10—C15	1.400 (3)
O1—C7	1.230 (2)	C10—C11	1.411 (3)
O2—C11	1.348 (2)	C11—C12	1.386 (3)
O2—H2A	0.8200	C12—C13	1.400 (3)
N—C13	1.366 (2)	C12—H12A	0.9300
N—C18	1.458 (3)	C13—C14	1.388 (3)
N—C16	1.496 (3)	C14—C15	1.371 (3)
C1—C2	1.388 (3)	C14—H14A	0.9300
C1—C6	1.389 (3)	C15—H15A	0.9300
C1—C7	1.514 (3)	C16—C17	1.448 (4)
C2—C3	1.382 (3)	C16—H16A	0.9700
C3—C4	1.371 (3)	C16—H16B	0.9700
C3—H3A	0.9300	C17—H17A	0.9600
C4—C5	1.378 (3)	C17—H17B	0.9600
C5—C6	1.377 (3)	C17—H17C	0.9600
C5—H5A	0.9300	C18—C19	1.508 (3)
C6—H6A	0.9300	C18—H18A	0.9700
C7—C8	1.436 (3)	C18—H18B	0.9700
C8—C9	1.349 (3)	C19—H19A	0.9600
C8—H8A	0.9300	C19—H19B	0.9600
C9—C10	1.440 (3)	C19—H19C	0.9600
C11—O2—H2A	109.5	C11—C12—C13	121.78 (19)
C13—N—C18	120.97 (19)	C11—C12—H12A	119.1
C13—N—C16	121.99 (19)	C13—C12—H12A	119.1
C18—N—C16	116.99 (18)	N—C13—C14	121.5 (2)
C2—C1—C6	117.0 (2)	N—C13—C12	121.31 (19)
C2—C1—C7	121.58 (19)	C14—C13—C12	117.15 (18)
C6—C1—C7	121.43 (19)	C15—C14—C13	120.9 (2)
C3—C2—C1	121.7 (2)	C15—C14—H14A	119.5
C3—C2—Cl1	118.13 (17)	C13—C14—H14A	119.5
C1—C2—Cl1	120.19 (17)	C14—C15—C10	123.4 (2)
C4—C3—C2	119.2 (2)	C14—C15—H15A	118.3
C4—C3—H3A	120.4	C10—C15—H15A	118.3
C2—C3—H3A	120.4	C17—C16—N	111.3 (2)
C3—C4—C5	121.0 (2)	C17—C16—H16A	109.4
C3—C4—Cl2	118.46 (19)	N—C16—H16A	109.4
C5—C4—Cl2	120.49 (18)	C17—C16—H16B	109.4
C6—C5—C4	118.6 (2)	N—C16—H16B	109.4
C6—C5—H5A	120.7	H16A—C16—H16B	108.0
C4—C5—H5A	120.7	C16—C17—H17A	109.5
C5—C6—C1	122.4 (2)	C16—C17—H17B	109.5
C5—C6—H6A	118.8	H17A—C17—H17B	109.5
C1—C6—H6A	118.8	C16—C17—H17C	109.5
O1—C7—C8	122.0 (2)	H17A—C17—H17C	109.5
O1—C7—C1	119.24 (17)	H17B—C17—H17C	109.5
C8—C7—C1	118.71 (19)	N—C18—C19	115.0 (2)
C9—C8—C7	122.9 (2)	N—C18—H18A	108.5
C9—C8—H8A	118.6	C19—C18—H18A	108.5
C7—C8—H8A	118.6	N—C18—H18B	108.5
C8—C9—C10	131.3 (2)	C19—C18—H18B	108.5
C8—C9—H9A	114.3	H18A—C18—H18B	107.5
C10—C9—H9A	114.3	C18—C19—H19A	109.5
C15—C10—C11	115.45 (17)	C18—C19—H19B	109.5
C15—C10—C9	118.67 (19)	H19A—C19—H19B	109.5
C11—C10—C9	125.80 (19)	C18—C19—H19C	109.5
O2—C11—C12	121.08 (18)	H19A—C19—H19C	109.5
O2—C11—C10	117.69 (16)	H19B—C19—H19C	109.5
C12—C11—C10	121.22 (19)
C6—C1—C2—C3	1.4 (3)	C15—C10—C11—O2	177.35 (18)
C7—C1—C2—C3	−177.62 (18)	C9—C10—C11—O2	−5.9 (3)
C6—C1—C2—Cl1	−179.63 (15)	C15—C10—C11—C12	−2.6 (3)
C7—C1—C2—Cl1	1.3 (3)	C9—C10—C11—C12	174.15 (19)
C1—C2—C3—C4	0.0 (3)	O2—C11—C12—C13	−178.17 (19)
Cl1—C2—C3—C4	−178.97 (15)	C10—C11—C12—C13	1.8 (3)
C2—C3—C4—C5	−2.2 (3)	C18—N—C13—C14	6.4 (3)
C2—C3—C4—Cl2	177.41 (15)	C16—N—C13—C14	−176.3 (2)
C3—C4—C5—C6	2.9 (3)	C18—N—C13—C12	−174.1 (2)
Cl2—C4—C5—C6	−176.74 (16)	C16—N—C13—C12	3.1 (3)
C4—C5—C6—C1	−1.4 (3)	C11—C12—C13—N	−178.2 (2)
C2—C1—C6—C5	−0.7 (3)	C11—C12—C13—C14	1.3 (3)
C7—C1—C6—C5	178.32 (19)	N—C13—C14—C15	176.1 (2)
C2—C1—C7—O1	−75.2 (3)	C12—C13—C14—C15	−3.4 (3)
C6—C1—C7—O1	105.8 (2)	C13—C14—C15—C10	2.6 (4)
C2—C1—C7—C8	101.6 (2)	C11—C10—C15—C14	0.5 (3)
C6—C1—C7—C8	−77.4 (3)	C9—C10—C15—C14	−176.5 (2)
O1—C7—C8—C9	−177.0 (2)	C13—N—C16—C17	−88.9 (3)
C1—C7—C8—C9	6.3 (3)	C18—N—C16—C17	88.5 (3)
C7—C8—C9—C10	−173.9 (2)	C13—N—C18—C19	77.2 (3)
C8—C9—C10—C15	−175.7 (2)	C16—N—C18—C19	−100.2 (3)
C8—C9—C10—C11	7.7 (4)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2A···O1^i	0.82	1.94	2.751 (2)	173
C12—H12A···O1^i	0.93	2.50	3.205 (3)	132

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