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tert Butyl 1,4 dioxo 3,6 di­phenyl 1,2,4,5 tetra­hydro­pyrrolo­[3,4 c]­pyrrole 2 carboxyl­ate

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organic papers

o816

Yasuo Imuraet al. C

23H20N2O4 doi:10.1107/S1600536805005829 Acta Cryst.(2005). E61, o816–o818 Acta Crystallographica Section E

Structure Reports Online

ISSN 1600-5368

tert

-Butyl

1,4-dioxo-3,6-diphenyl-1,2,4,5-tetra-hydropyrrolo[3,4-

c

]pyrrole-2-carboxylate

Yasuo Imura, Takatoshi Senju and Jin Mizuguchi*

Department of Applied Physics, Graduate School of Engineering, Yokohama National University, Tokiwadai 79-5, Hodogaya-ku, Yokohama 240-850, Japan

Correspondence e-mail: mizu-j@ynu.ac.jp

Key indicators

Single-crystal X-ray study

T= 93 K

Mean(C–C) = 0.003 A˚

Rfactor = 0.051

wRfactor = 0.141

Data-to-parameter ratio = 12.6

For details of how these key indicators were automatically derived from the article, see http://journals.iucr.org/e.

#2005 International Union of Crystallography Printed in Great Britain – all rights reserved

The title compound, C23H20N2O4, is a soluble precursor

(‘latent pigment’) of diketopyrrolopyrrole pigments. Thetert -butoxycarbonyl group is twisted by 78.5 (1) with respect to

the heterocyclic ring system. In the crystal structure, pairs of molecules form centrosymmetric dimers through N—H O intermolecular hydrogen bonds and are stacked in a herring-bone fashion along theaaxis.

Comment

The title compound, (I), is a soluble precursor (‘latent pigment’) (Zambounis et al., 1994, 1997) of diketopyrrolo-pyrrole (DPP), an industrially important red pigment (Herbst & Hunger, 1993). The soluble precursor is prepared by replacing the H atom of the NH group by a tert -butoxy-carbonyl (t-BOC) group. Both mono- and disubstitutedt-BOC DPPs can be prepared. The former is called mono-BOC DPP while the latter is simply t-BOC DPP. The insoluble parent DPP can then be regenerated by thermal decomposition of the precursor at around 450 K. The present ‘latent pigment technology’ has recently attracted attention as a versatile and promising technique for the preparation of pigment nano-particles as well as transparent thin films for electronic and imaging applications. The structure of t-BOC DPP has previously been published (MacLeanet al., 2000; Mizuguchi, 2003a,b). The present paper reports the structure of mono-BOC DPP, (I).

The title compound is shown in Fig. 1. The phenyl rings deviate asymmetrically from the heterocyclic system in the same direction by 4.4 (1) (N1/C1/C2/C5/C6 and C7/C8/C9/ C10/C11/C12) and 9.3 (1) (N2/C1/C2/C3/C4 and C13/C14/

C15/C16/C17/C18). Thet-BOC group attached to the N atom of the heterocyclic ring is twisted with respect to the hetero-cyclic system by 78.5 (1) (N2/C1/C2/C3/C4 and O3/O4/C19/ C20). Furthermore, the heterocyclic ring system is not entirely planar, but is folded in the middle with a dihedral angle of 177.6 (1)between the two five-membered rings. Fig. 2 shows

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the projection of the structure on to thebcplane. In the crystal structure, pairs of molecules form centrosymmetric dimers through N—H O intermolecular hydrogen bonds between the NH group of one molecule and the carbonyl group of a neighboring molecule. However, as shown in Fig. 3, there is a small step of about 0.84 A˚ between the two molecular planes

of a centrosymmetric pair. The molecules are stacked in a herring-bone fashion along theaaxis.

Experimental

Mono-BOC DPP was prepared according to a method described in the literature (Zambouniset al., 1994). The product was purified by column chromatography. Single crystals of mono-BOC DPP were grown from a dichloromethane–ethyl acetate solution.

Crystal data

C23H20N2O4

Mr= 388.41

Monoclinic,P21=n

a= 6.0502 (6) A˚

b= 16.524 (2) A˚

c= 19.031 (2) A˚

= 95.744 (7)

V= 1893.0 (4) A˚3

Z= 4

Dx= 1.363 Mg m

3

CuKradiation

Cell parameters from 11787 reflections

= 3.5–68.1

= 0.77 mm1

T= 93.2 K Needle, orange 0.500.100.05 mm

Data collection

Rigaku R-AXIS RAPID imaging plate diffractometer

!scans

Absorption correction: multi-scan (ABSCOR; Higashi, 1995)

Tmin= 0.683,Tmax= 0.962

17683 measured reflections

3329 independent reflections 2370 reflections withF2> 2(F2)

Rint= 0.052

max= 68.3

h=6!6

k=19!19

l=22!22

Refinement

Refinement onF2

R[F2> 2(F2)] = 0.051

wR(F2) = 0.141

S= 1.08 3329 reflections 265 parameters

H atoms treated by a mixture of independent and constrained refinement

w= 1/[2(F

o2) + {0.05[Max(Fo2,0) +

2Fc2]/3}2]

(/)max< 0.001

max= 0.28 e A˚

3

min=0.31 e A˚

3

Table 1

Selected geometric parameters (A˚ ,).

N1—C5 1.395 (3)

N1—C6 1.395 (3)

N2—C3 1.427 (3)

N2—C4 1.404 (3)

C1—C2 1.425 (3)

C1—C4 1.382 (3)

C1—C5 1.455 (3)

C2—C3 1.449 (3)

C2—C6 1.379 (3)

C5—N1—C6 112.6 (2)

C3—N2—C4 112.7 (2)

C2—C1—C4 110.1 (2)

C2—C1—C5 107.3 (2)

C4—C1—C5 142.5 (2)

C1—C2—C3 108.3 (2)

C1—C2—C6 109.5 (2)

C3—C2—C6 142.2 (2)

N2—C3—C2 103.1 (2)

N2—C4—C1 105.7 (2)

N1—C5—C1 104.2 (2)

N1—C6—C2 106.4 (2)

organic papers

Acta Cryst.(2005). E61, o816–o818 Yasuo Imuraet al. C

[image:2.610.66.279.72.377.2]

23H20N2O4

o817

Figure 1

[image:2.610.312.566.74.143.2]

A view of the molecular structure of (I), showing 50% displacement ellipsoids for non-H atoms.

Figure 2

Projection on to thebc plane, showing the N—H O intermolecular hydrogen bonds as dotted lines. H atoms not involved in hydrogen bonding have been omitted.

Figure 3

[image:2.610.47.293.415.625.2]
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[image:3.610.44.294.110.146.2]

Table 2

Hydrogen-bonding geometry (A˚ ,).

D—H A D—H H A D A D—H A

N1—H1N O1i

0.94 (2) 1.90 (2) 2.821 (2) 166 (2)

Symmetry code: (i) 1x;1y;1z.

The H atom attached to the N atom was located in a difference density map and its coordinates were refined, with Uiso(H) = 1.2Ueq(N). The remainder of the H atoms were positioned geom-etrically and included in a riding-model approximation with C—H = 0.95 A˚ andUiso(H) = 1.2Ueq(C).

Data collection: PROCESS-AUTO (Rigaku, 1998); cell refine-ment: PROCESS-AUTO; data reduction: TEXSAN (Molecular Structure Corporation, 2001); program(s) used to solve structure:

SHELXS86(Sheldrick, 1985); program(s) used to refine structure:

TEXSAN; molecular graphics: ORTEPIII (Burnett & Johnson, 1996); software used to prepare material for publication:TEXSAN.

References

Burnett, M. N. & Johnson, C. K. (1996).ORTEPIII. Report ORNL-6895. Oak Ridge National Laboratory, Tennessee, USA.

Herbst, W. & Hunger, K. (1993).Industrial Organic Pigments, pp. 550–552. Weinheim: VCH.

Higashi, T. (1995).ABSCOR.Rigaku Corporation, Tokyo, Japan.

MacLean, E. J., Tremayne, M., Kariuki, B. M., Harris, K. D. M., Iqbal, A. F. M. & Hao, Z. (2000).J. Chem. Soc. Perkin Trans.2, pp. 1513–1519.

Mizuguchi, J. (2003a).Z. Kristallogr. New Cryst. Struct.218, 134–136. Mizuguchi, J. (2003b).Acta Cryst.E59, o469–o471.

Molecular Structure Corporation (2001).TEXSAN.Version 1.11. MSC, 9009 New Trails Drive, The Woodlands, TX 77381-5209, USA.

Rigaku (1998).PROCESS-AUTO. Rigaku Corporation, Tokyo, Japan. Sheldrick, G. M. (1985).SHELXS86. University of Go¨ttingen, Germany. Zambounis, J., Hao, H. & Iqbal, A. (1994). US Patent No. 5 484 943. Zambounis, J., Hao, H. & Iqbal, A. (1997).Nature(London),388, 131–132.

organic papers

o818

Yasuo Imuraet al. C

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supporting information

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Acta Cryst. (2005). E61, o816–o818

supporting information

Acta Cryst. (2005). E61, o816–o818 [https://doi.org/10.1107/S1600536805005829]

tert

-Butyl 1,4-dioxo-3,6-diphenyl-1,2,4,5-tetrahydropyrrolo[3,4-

c

]pyrrole-2-carboxylate

Yasuo Imura, Takatoshi Senju and Jin Mizuguchi

tert-Butyl 1,4-dioxo-3,6-diphenyl-1,2,4,5-tetrahydropyrrolo[3,4-c]pyrrole-2-carboxylate

Crystal data

C23H20N2O4 Mr = 388.41 Monoclinic, P21/n Hall symbol: -P 2yn a = 6.0502 (6) Å b = 16.524 (2) Å c = 19.031 (2) Å β = 95.744 (7)° V = 1893.0 (4) Å3 Z = 4

F(000) = 816.0 Dx = 1.363 Mg m−3

Cu radiation, λ = 1.5418 Å

Cell parameters from 11787 reflections θ = 3.5–68.1°

µ = 0.77 mm−1 T = 93 K Needle, orange 0.50 × 0.10 × 0.05 mm

Data collection

Rigaku R-AXIS RAPID Imaging Plate diffractometer

Detector resolution: 10.00 pixels mm-1 72 frames, Δ ω = 10° scans

Absorption correction: multi-scan (ABSCOR; Higashi, 1995) Tmin = 0.683, Tmax = 0.962 17683 measured reflections

3329 independent reflections 2370 reflections with F2 > 2σ(F2) Rint = 0.052

θmax = 68.3° h = −6→6 k = −19→19 l = −22→22

Refinement

Refinement on F2 R[F2 > 2σ(F2)] = 0.051 wR(F2) = 0.141 S = 1.08 3329 reflections 265 parameters

H atoms treated by a mixture of independent and constrained refinement

w = 1/[σ2(F

o2) + {0.05[Max(Fo2,0) + 2Fc2]/3}2] (Δ/σ)max = 0.0003

Δρmax = 0.28 e Å−3 Δρmin = −0.31 e Å−3

Special details

Refinement. Refinement using reflections with F2 > -10.0 σ(F2). The weighted R-factor (wR) and goodness of fit (S) are based on F2. R-factor (gt) are based on F. The threshold expression of F2 > 2 σ(F2) is used only for calculating R-factor (gt).

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

x y z Uiso*/Ueq

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Acta Cryst. (2005). E61, o816–o818

O2 0.2487 (3) 0.63815 (10) 0.19288 (8) 0.0321 (5)

O3 0.5302 (3) 0.5064 (1) 0.09514 (9) 0.0362 (5)

O4 0.6918 (2) 0.62674 (9) 0.12789 (8) 0.0273 (4)

N1 0.3505 (3) 0.5308 (1) 0.41702 (10) 0.0266 (5)

N2 0.5512 (3) 0.5515 (1) 0.21071 (10) 0.0258 (5)

C1 0.5364 (4) 0.5121 (1) 0.3217 (1) 0.0250 (6)

C2 0.3569 (4) 0.5669 (1) 0.3048 (1) 0.0243 (6)

C3 0.3629 (4) 0.5932 (1) 0.2324 (1) 0.0264 (6)

C4 0.6549 (4) 0.5017 (1) 0.2640 (1) 0.0253 (6)

C5 0.5350 (4) 0.4904 (1) 0.3958 (1) 0.0257 (6)

C6 0.2423 (4) 0.5778 (1) 0.3632 (1) 0.0244 (6)

C7 0.0459 (4) 0.6246 (1) 0.3742 (1) 0.0262 (6)

C8 −0.0509 (4) 0.6215 (1) 0.4379 (1) 0.0283 (7)

C9 −0.2418 (4) 0.6649 (1) 0.4465 (1) 0.0299 (7)

C10 −0.3382 (4) 0.7128 (2) 0.3917 (1) 0.0345 (7)

C11 −0.2432 (4) 0.7169 (1) 0.3286 (1) 0.0325 (7)

C12 −0.0541 (4) 0.6726 (1) 0.3193 (1) 0.0294 (7)

C13 0.8493 (4) 0.4510 (1) 0.2559 (1) 0.0245 (6)

C14 0.9746 (4) 0.4548 (1) 0.1979 (1) 0.0310 (7)

C15 1.1575 (4) 0.4054 (2) 0.1940 (1) 0.0319 (7)

C16 1.2211 (4) 0.3512 (1) 0.2476 (1) 0.0343 (7)

C17 1.0993 (4) 0.3470 (1) 0.3057 (1) 0.0357 (7)

C18 0.9168 (4) 0.3965 (1) 0.3098 (1) 0.0325 (7)

C19 0.5905 (4) 0.5576 (1) 0.1373 (1) 0.0268 (6)

C20 0.7371 (4) 0.6527 (1) 0.0553 (1) 0.0287 (7)

C21 0.8436 (5) 0.7349 (2) 0.0702 (1) 0.0402 (8)

C22 0.8985 (4) 0.5941 (2) 0.0270 (1) 0.0328 (7)

C23 0.5206 (4) 0.6589 (2) 0.0090 (1) 0.0366 (7)

H1N 0.325 (4) 0.533 (1) 0.465 (1) 0.0319*

H8 0.0152 0.5892 0.4757 0.0340*

H9 −0.3071 0.6619 0.4897 0.0358*

H10 −0.4691 0.7428 0.3976 0.0413*

H11 −0.3082 0.7503 0.2914 0.0390*

H12 0.0082 0.6748 0.2754 0.0353*

H14 0.9334 0.4918 0.1607 0.0372*

H15 1.2402 0.4088 0.1543 0.0383*

H16 1.3465 0.3172 0.2447 0.0412*

H17 1.1417 0.3099 0.3428 0.0429*

H18 0.8361 0.3934 0.3500 0.0390*

H21A 0.9737 0.7287 0.1022 0.0483*

H21B 0.7418 0.7694 0.0906 0.0483*

H21C 0.8821 0.7579 0.0274 0.0483*

H22A 1.0338 0.5942 0.0570 0.0393*

H22B 0.8366 0.5412 0.0254 0.0393*

H22C 0.9266 0.6101 −0.0192 0.0393*

H23A 0.4483 0.6078 0.0069 0.0439*

H23B 0.5489 0.6749 −0.0372 0.0439*

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Acta Cryst. (2005). E61, o816–o818 Atomic displacement parameters (Å2)

U11 U22 U33 U12 U13 U23

O1 0.036 (1) 0.0324 (9) 0.0225 (8) 0.0067 (8) 0.0020 (7) 0.0025 (7)

O2 0.0312 (10) 0.0379 (10) 0.0269 (9) 0.0024 (8) 0.0008 (7) 0.0046 (8)

O3 0.048 (1) 0.0341 (10) 0.0260 (9) −0.0099 (8) 0.0027 (8) −0.0044 (8)

O4 0.0349 (10) 0.0269 (8) 0.0210 (8) −0.0040 (7) 0.0063 (7) 0.0009 (7)

N1 0.028 (1) 0.031 (1) 0.021 (1) 0.0023 (9) 0.0045 (9) 0.0001 (8)

N2 0.029 (1) 0.031 (1) 0.0181 (10) 0.0014 (9) 0.0042 (8) 0.0017 (8)

C1 0.028 (1) 0.029 (1) 0.019 (1) −0.001 (1) 0.0022 (9) 0.0003 (9)

C2 0.024 (1) 0.028 (1) 0.021 (1) 0.000 (1) 0.0026 (9) 0.0021 (10)

C3 0.028 (1) 0.029 (1) 0.022 (1) −0.000 (1) 0.0002 (10) 0.0008 (10)

C4 0.030 (1) 0.023 (1) 0.022 (1) −0.003 (1) −0.0001 (10) −0.0017 (9)

C5 0.029 (1) 0.027 (1) 0.022 (1) −0.002 (1) 0.0033 (10) 0.0010 (10)

C6 0.026 (1) 0.023 (1) 0.025 (1) −0.0025 (10) 0.0007 (10) −0.0000 (9)

C7 0.026 (1) 0.026 (1) 0.027 (1) −0.004 (1) 0.0034 (10) −0.0011 (10)

C8 0.031 (1) 0.028 (1) 0.026 (1) −0.003 (1) 0.003 (1) −0.0026 (10)

C9 0.029 (1) 0.034 (1) 0.027 (1) −0.001 (1) 0.004 (1) −0.006 (1)

C10 0.029 (1) 0.034 (1) 0.041 (1) 0.001 (1) 0.004 (1) −0.009 (1)

C11 0.032 (1) 0.028 (1) 0.037 (1) 0.003 (1) 0.001 (1) 0.001 (1)

C12 0.030 (1) 0.029 (1) 0.029 (1) −0.002 (1) 0.003 (1) 0.000 (1)

C13 0.026 (1) 0.024 (1) 0.023 (1) −0.0035 (10) 0.0028 (9) −0.0026 (10)

C14 0.031 (1) 0.033 (1) 0.028 (1) −0.002 (1) 0.003 (1) 0.001 (1)

C15 0.031 (1) 0.036 (1) 0.030 (1) −0.000 (1) 0.006 (1) −0.005 (1)

C16 0.034 (1) 0.032 (1) 0.037 (1) 0.001 (1) 0.004 (1) −0.006 (1)

C17 0.041 (2) 0.032 (1) 0.034 (1) 0.009 (1) 0.006 (1) 0.004 (1)

C18 0.036 (1) 0.035 (1) 0.028 (1) 0.003 (1) 0.009 (1) −0.000 (1)

C19 0.030 (1) 0.029 (1) 0.022 (1) −0.001 (1) 0.0036 (10) 0.003 (1)

C20 0.036 (1) 0.032 (1) 0.020 (1) 0.001 (1) 0.010 (1) 0.0026 (10)

C21 0.048 (2) 0.033 (1) 0.041 (2) −0.005 (1) 0.012 (1) 0.003 (1)

C22 0.032 (2) 0.040 (1) 0.028 (1) 0.001 (1) 0.009 (1) 0.002 (1)

C23 0.042 (2) 0.038 (1) 0.029 (1) 0.008 (1) 0.005 (1) 0.007 (1)

Geometric parameters (Å, º)

O1—C5 1.236 (3) C11—C12 1.385 (3)

O2—C3 1.221 (3) C11—H11 0.950

O3—C19 1.196 (3) C12—H12 0.950

O4—C19 1.317 (3) C13—C14 1.403 (3)

O4—C20 1.498 (2) C13—C18 1.394 (3)

N1—C5 1.395 (3) C14—C15 1.383 (3)

N1—C6 1.395 (3) C14—H14 0.950

N1—H1N 0.94 (2) C15—C16 1.382 (3)

N2—C3 1.427 (3) C15—H15 0.950

N2—C4 1.404 (3) C16—C17 1.391 (3)

N2—C19 1.445 (3) C16—H16 0.950

C1—C2 1.425 (3) C17—C18 1.383 (3)

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Acta Cryst. (2005). E61, o816–o818

C1—C5 1.455 (3) C18—H18 0.950

C2—C3 1.449 (3) C20—C21 1.517 (3)

C2—C6 1.379 (3) C20—C22 1.512 (3)

C4—C13 1.465 (3) C20—C23 1.508 (3)

C6—C7 1.450 (3) C21—H21A 0.950

C7—C8 1.400 (3) C21—H21B 0.950

C7—C12 1.401 (3) C21—H21C 0.950

C8—C9 1.382 (3) C22—H22A 0.950

C8—H8 0.950 C22—H22B 0.950

C9—C10 1.390 (3) C22—H22C 0.950

C9—H9 0.950 C23—H23A 0.950

C10—C11 1.384 (3) C23—H23B 0.950

C10—H10 0.950 C23—H23C 0.950

O1···N1i 2.821 (2) H1N···H1Ni 2.64 (5)

C5···H1Ni 2.73 (2)

C19—O4—C20 120.3 (2) C6—C7—C8 121.7 (2)

C5—N1—C6 112.6 (2) C6—C7—C12 119.6 (2)

C5—N1—H1N 121 (1) C8—C7—C12 118.7 (2)

C6—N1—H1N 125 (1) C7—C8—C9 120.6 (2)

C3—N2—C4 112.7 (2) C8—C9—C10 120.0 (2)

C3—N2—C19 117.4 (2) C9—C10—C11 119.9 (2)

C4—N2—C19 129.4 (2) C10—C11—C12 120.4 (2)

C2—C1—C4 110.1 (2) C7—C12—C11 120.3 (2)

C2—C1—C5 107.3 (2) C4—C13—C14 124.1 (2)

C4—C1—C5 142.5 (2) C4—C13—C18 118.1 (2)

C1—C2—C3 108.3 (2) C14—C13—C18 117.8 (2)

C1—C2—C6 109.5 (2) C13—C14—C15 120.9 (2)

C3—C2—C6 142.2 (2) C14—C15—C16 120.6 (2)

O2—C3—N2 122.3 (2) C15—C16—C17 119.2 (2)

O2—C3—C2 134.5 (2) C16—C17—C18 120.3 (2)

N2—C3—C2 103.1 (2) C13—C18—C17 121.2 (2)

N2—C4—C1 105.7 (2) O3—C19—O4 129.6 (2)

N2—C4—C13 124.4 (2) O3—C19—N2 122.0 (2)

C1—C4—C13 129.9 (2) O4—C19—N2 108.4 (2)

O1—C5—N1 122.9 (2) O4—C20—C21 101.3 (2)

O1—C5—C1 132.9 (2) O4—C20—C22 109.2 (2)

N1—C5—C1 104.2 (2) O4—C20—C23 109.3 (2)

N1—C6—C2 106.4 (2) C21—C20—C22 111.2 (2)

N1—C6—C7 121.5 (2) C21—C20—C23 112.1 (2)

C2—C6—C7 132.1 (2) C22—C20—C23 112.9 (2)

Symmetry code: (i) −x+1, −y+1, −z+1.

Hydrogen-bond geometry (Å, º)

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Acta Cryst. (2005). E61, o816–o818

N1—H1N···O1i 0.94 (2) 1.90 (2) 2.821 (2) 166 (2)

Figure

Figure 1� = 95.744 (7)�V = 1893.0 (4) A˚A view of the molecular structure of (I), showing 50% displacement 3
Table 2

References

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