Research ArticleSynthesis and X-Ray Crystal Structure ofTwo Acridinedione Derivatives

Dalbir Kour,1 D. R. Patil,2 M. B. Deshmukh,2 Vivek K. Gupta,1 and Rajni Kant1

1 X-Ray Crystallography Laboratory, Post-Graduate Department of Physics & Electronics, University of Jammu,Jammu Tawi 180 006, India

2Department of Chemistry, Shivaji University, Kolhapur 416 004, India

Correspondence should be addressed to Rajni Kant; rkvk.paper11@gmail.com

Received 23 August 2013; Revised 27 December 2013; Accepted 13 January 2014; Published 27 February 2014

Academic Editor: Miao Du

Copyright © 2014 Dalbir Kour et al. This is an open access article distributed under the Creative Commons Attribution License,which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

The two acridinedione derivatives 1 [3,3,6,6-tetramethyl-9-(4-methoxyphenyl)-3,4,6,7,9,10-hexahydro-2H,5H-acridine-1,8-dione(C24H29NO3)] and 2 [3,3,6,6-tetramethyl-9-(4-methylphenyl)-3,4,6,7,9,10-hexa-hydro-2H,5H-acridine-1,8-dione (C

24H29NO2)]

were synthesized and their crystal structures were determined by direct methods. The asymmetric unit of compound 1 containstwo independent molecules. The 1,4-dihydropyridine (DHP) ring adopts boat conformation in both 1 and 2. In 1 the dione ringsexist in sofa conformation (for both the crystallographically independent molecules) while the corresponding rings in 2 adopt halfchair and sofa conformations, respectively.The crystal packing is stabilized by intermolecular N–H⋅ ⋅ ⋅O and C–H⋅ ⋅ ⋅O interactionsin compound 1 and N–H⋅ ⋅ ⋅O interactions in compound 2.

1. Introduction

A multicomponent reaction (MCR) provides powerful toolfor the synthesis of complex molecules and drug like hetero-cycles and has great interest in diversity oriented synthesis.MCRs are economic, selective, plain procedure and timeand power saving with being ecofriendly in organic syn-thesis [1–3]. Acridinediones containing a 1,4-DHP nucleusare used as laser dyes with very high efficiencies of photoinitiators [4, 5]. A latest literature review reveals that 1,4-DHPnucleus exhibits calcium channels blockers and antiaggre-gatory activity. Besides this, 1,4-DHP skeleton shows manybiological activities such as antihypertension, anticancer,antidiabetics, geroprotective, neuroprotectant, and anti-HIV[6]. Synthesis of 1,8-dioxoacridinedione is usually carried outby MCRs of dimedone, aldehydes, and ammonium acetate[7, 8]. In continuation of our ongoing work on multi-component reaction derivatives and their crystal structureanalyses [9, 10], we report the synthesis and crystal struc-ture of 3,3,6,6-tetramethyl-9-(4-methoxyphenyl)-3,4,6,7,9,10hexahydroacridine-1,8-dione 1 and 3,3,6,6-tetramethyl-9-(4-methylphenyl)-3,4,6,7,9,10 hexahydroacridine-1,8-dione 2(Scheme 1).

2. Materials and Methods

All the chemicals were purchased from SD Fine ChemLimited andThomas Baker, used as received without furtherpurification. Melting point was determined on Labstar melt-ing apparatus. The IR spectra were recorded on a Perkin-Elmer, FTIR-1600 spectrophotometer and expressed in cm−1(KBr). 1H NMR spectra were recorded on Bruker Avance(300MHz) spectrometer in DMSO-d6 using TMS as theinternal standard. Elemental analysis was performed on aEURO-EA analyzer.

2.1. Synthesis of 3,3,6,6-Tetramethyl-9-(4-methoxyphenyl)-3,4,6,7,9,10-hexahydroacridine-1,8-dione (1) and 3,3,6,6-Tetramethyl-9-(4-methylphenyl)-3,4,6,7,9,10-hexahydroacri-dine-1,8-dione (2). In a 50mL rounded bottom flask,a mixture of dimedone (2mmole), 4-methoxy or 4-methyl benzaldehyde (1mmole), and ammonium acetate(1.2mmole) in mixture of aqueous ethanol (5mL) was stirredat RT for 5min. To this [CMIM][HSO

4] (20mol%) was

added and the reaction mixture heated at 85∘C till comple-tion of reaction. The progress of reaction was monitored byTLC. After completion of reaction, themixture was gradually

Hindawi Publishing CorporationJournal of CrystallographyVolume 2014, Article ID 914504, 8 pageshttp://dx.doi.org/10.1155/2014/914504

2 Journal of Crystallography

OO O

O

2

1 2 3 4

H3CH3C

H3CH3C

R

R

NH

+ + NH4OAc

R = OCH3R = CH3

[CMIM][HSO4]

EtOH:H2OCH3

CH3

R = OCH3 = Compound 1R = CH3 = Compound 2

Scheme 1: Synthesis of compounds 1 and 2.

C26B

O25B

C22B C21B

C23B

C24B

C20B

C19B

C9BO1B

C1B

C2BC15B

C3B

C16B

C4B

N12BC13B

C17B

C10B

C14B

O8B

C8B

C7B

C6B

C18B

C5B

C18AC5A

N12A

C13A

C14A

C11A

C10A

C1A

C2A

C23A

C22A

O25A

C26A

C16A

C3A

C15A

C6A

C7A

O8AC8A

C9A

C19A

C20A

C21A

C24A

C17A

O1A

C4A

Figure 1: ORTEP view of the molecule with displacement ellipsoids drawn at 50% probability level. H atoms are shown as small spheres ofarbitrary radii.

Journal of Crystallography 3

C25

C22

C21

C20C23

O1

C1C10

C9

C14 C8

C7

C17

C6C5

C13N12

C11C4

C3

C2

C15

C16

C18

O8

C19

C24

Figure 2: ORTEP view of the molecule with displacement ellipsoids drawn at 50% probability level. H atoms are shown as small spheres ofarbitrary radii.

cooled to RT and poured on ice water under stirring; solidswere precipitated out. Filter the product and dry it.The crudeproducts were recrystallized from ethanol and characterizedby IR, 1H NMR, and elemental and single crystal analysis.

Compound 1

M.P.: 308–311∘C, Yield: 80%.IR (KBr): 3431, 3298, 2963, 1657, 1619 cm−1.1H NMR (300MHz, DMSO-d6): 𝛿 1.03 (s, 6H, CH3),1.15 (s, 6H, CH

3), 2.31–2.43 (m, 8H, CH

2), 3.92 (s, 3H,

OCH3), 5.01 (s, 1H, CH), 6.78–7.31 (m, 4H. Ar–H),

8.97 (bs, 1H, NH).Analysis calculated for C

24H29NO3

(379.491): C,75.96%; H, 7.70%; N, 3.69%.Found: C, 75.91%; H, 7.64%; N, 3.74%.

Compound 2

M.P.: 325–327∘C, Yield: 85%.IR (KBr): 3415, 3298, 2959, 1641, 1613 cm−1.1HNMR (300MHz, DMSO-d6): 𝛿 0.98 (s, 6H, CH3),1.08 (s, 6H, CH

3), 2.19 (s, 3H, CH

3), 2.23–2.41 (m, 8H,

CH2), 5.08 (s, 1H, CH), 6.97–7.21 (m, 4H. Ar–H), 8.72

(bs, 1H, NH).

Analysis calculated for C24H29NO2(363.429): C,

79.30%; H, 8.04%; N, 3.85%.

Found: C, 79.26%; H, 7.99%; N, 3.90%.

2.2. X-Ray Analysis. A summary of the crystallographic datais given in Table 1. The X-ray intensity data of a well-definedcrystal for 1 and 2 (0.30 × 0.20 × 0.10mm) were collectedat room temperature (293K) by using a CCD area-detectordiffractometer (X’calibur system, Oxford diffraction, 2010)which is equipped with graphite monochromated MoK𝛼radiation (𝜆 = 0.71073 Å). The cell dimensions weredetermined by the least-squares fit of angular settings of 14203(1) and 11474 (2) reflections in the 𝜃 range 3.48 to 29.04∘ (1)and 3.99 to 23.48∘ (2), respectively. Data were corrected forLorentz, polarization, and absorption factors.

The structure elucidation and full-matrix least-squaresrefinement were carried out by using SHELXL97 software[11].The geometry of themolecule is determined by PLATON[12]. All the hydrogen atoms were geometrically fixed andallowed to ride on the corresponding non-H atoms with C-H distances of 0.93–0.98 Å and with 𝑈iso(H) = 1.2𝑈eq(C),

4 Journal of Crystallography

a

co

a

b

o

(a)

(b)

Figure 3: The crystal packing as seen along the direction of hydrogen bonded chains in 1 (a) and 2 (b).

Journal of Crystallography 5

Table 1: Crystallographic data for 1 and 2.

Compound

1 2CCDC number 946763 954009Crystal description Yellow block Yellow blockCrystal size 0.30 × 0.20 × 0.10mm 0.30 × 0.20 × 0.10mmEmpirical formula C24H29NO3 C24H29NO2Formula weight 379.48 363.48Radiation, wavelength Mo K𝛼, 0.71073 Å Mo K𝛼, 0.71073 Å

Unit cell dimensions𝑎 = 15.1263(5),𝑏 = 14.1430(4),𝑐 = 20.6652(7) Å

𝑎 = 14.0214(4),𝑏 = 14.5994(5),𝑐 = 10.4505(4) Å

Crystal system, space group Orthorhombic, P bc21 Orthorhombic, P na21Unit cell volume 4420.9(2) Å3 2139.3(1) Å3

Number of molecules per unit cell,𝑍

8 4

Absorption coefficient 0.074mm−1 0.071mm−1

𝐹(000) 1632 784𝜃 range for entire data collection 3.49 < 𝜃 < 26.00 3.70 < 𝜃 < 26.00Reflections collected/unique 35396/8473 30978/4180Reflections observed (𝐼 > 2𝜃(𝐼)) 5169 3098

Range of indices ℎ = −18 to 18, 𝑘 = −17 to 17,𝑙 = −23 to 25

ℎ = −17 to 17, 𝑘 = −18 to 18,𝑙 = −12 to 12

Final 𝑅-factor 0.057 0.053𝑤𝑅(𝐹2) 0.1249 0.1281𝑅int 0.0683 0.0476Goodness-of-fit 1.001 1.037Final residual electron density −0.187 < Δ𝜌 < 0.194 𝑒Å−3 −0.121 < Δ𝜌 < 0.196 𝑒Å−3

except for the methyl groups where 𝑈iso(H) = 1.5𝑈eq(C).Multiscan absorption correction was employed (with 𝑇min= 0.65162 (1); 0.90012 (2) and 𝑇max = 1.00000 (for both1 and 2, resp.)) [13]. Atomic scattering factors were takenfrom International Tables for X-Ray Crystallography (1992,Vol. C, Tables 4.2.6.8 and 6.1.1.4). The crystallographic dataare summarized in Table 1. CCDC-946763 (1) and CCDC-954009 (2) contain the supplementary crystallographic datafor both the structures.

3. Results and Discussion

Figures 1 and 2 show the perspective view of molecules1 and 2, respectively [14]. Table 2 presents selected geo-metrical parameters for both the structures. The asym-metric unit of compound 1 comprises two crystallograph-ically independent molecules, A and B (Figure 2). Bondlengths and angles are normal and correspond to thoseobserved in some related structures [15, 16]. The centralring (C9/C10/C11/N12/C13/C14) of the acridinedione moietyadopts a distorted boat conformation [molecule A: ΔCs(C9A–C12A) = 2.426 and ΔCs (C10A–C11A) = 7.72; molecule

B: ΔCs (C9B–C12B) = 1.014 and ΔCs (C10B–C11B) = 11.97].The benzene ring is held almost at right angles to the 1,4-DHPring (dihedral angles for molecules A and B being 87.32(13)∘and 86.49(12)∘, resp.). A comparison of 1,4-DHP ring is pre-sented in Table 3. Both the cyclohexanes exist in sofa confor-mations (molecule A: ΔCs (C3A) = 4.97; ΔCs (C6A) = 9.625;molecule B: ΔCs (C3B) = 6.917; ΔCs (C6B) = 10.82)) [17].

In molecule 2, the central ring (C9/C10/C11/N12/C13/C14) of the acridinedione moiety adopts a boat conforma-tion (ΔCs (C9–C12) = 2.22 and ΔCs (C10-C11) = 3.757).The cyclohexane comprising atoms (C5/C6/C7/C8/C14/C13)adopts half chair conformation (ΔC

2(C13-C14) = 9.63) while

the other one exists in sofa conformation (ΔCs (C10–C3)= 1.85) [17]. The dihedral angle between the 1,4-DHP ringand the phenyl ring (C19–C24) is 89.15(9)∘, which shows thatthe benzene ring is almost perpendicular to the central 1,4-dihydropyridine ring.The bond lengths of C11–N12 and C13–N12 are 1.354(3) ́Å and 1.376(3) ́Å, respectively, shorter thanthe normal C–N bond length of 1.47 ́Å.

Packing of molecules 1 and 2 in the unit cell is shownin Figure 3. The crystal packing is stabilized by the presenceof few intermolecular N–H⋅ ⋅ ⋅O and C–H⋅ ⋅ ⋅O interactions

6 Journal of Crystallography

Table 2: Selected bond lengths (Å) and selected bond angles (∘) for 1 and 2.

Molecule A Molecule BBond distances and bond angles for compound 1

O1A–C1A 1.211(4) O1B–C1B 1.234(4)C10A–C11A 1.350(4) C10B–C11B 1.355(4)C11A–N12A 1.382(4) C11B–N12B 1.381(4)N12A–C13A 1.372(5) N12B–C13B 1.360(5)C13A–C14A 1.359(5) C13B–C14B 1.344(5)C22A–O25A 1.367(6) C22B–O25B 1.363(6)O25A–C26A 1.432(6) O25B–C26B 1.409(7)O1A–C1A–C10A 121.1(3) O1B–C1B–C10B 120.4(4)O1A–C1A–C2A 121.4(3) O1B–C1B–C2B 121.4(3)O8A–C8A–C14A 120.3(4) O8B–C8B–C14B 122.1(5)O8A–C8A–C7A 121.5(4) O8B–C8B–C7B 120.3(4)C10A–C11A–N12A 119.8(3) C10B–C11B–N12B 120.3(3)N12A–C11A–C4A 115.7(3) N12B–C11B–C4B 115.8(3)C13A–N12A–C11A 121.9(3) C14B–C13B–N12B 121.6(4)C14A–C13A–N12A 119.8(4) N12B–C13B–C5B 115.2(3)N12A–C13A–C5A 116.1(3) C21B–C22B–O25B 116.4(5)O25A–C22A–C23A 124.9(5) O25B–C22B–C23B 124.9(5)O25A–C22A–C21A 115.7(5) C21B–C22B–O25B 116.4(5)C22A–O25A–C26A 117.0(4) C22B–O25B–C26B 118.6(4)

Bond distances and bond angles for compound 2O1–C1 1.232(3) C8–O8 1.225(3)C9–C10 1.507(4) C9–C14 1.522(3)C10–C11 1.354(3) C11–N12 1.354(3)N12–C13 1.376(3) C13–C14 1.345(3)O1–C1–C10 121.0(3) O1–C1–C2 119.1(2)C10–C1–C2 119.8(2) C1–C2–C3 114.9(2)C4–C3–C2 106.8(2) C11–C4–C3 114.0(2)C13–C5–C6 113.8(2) C5–C6–C7 109.4(3)C6–C7–C8 113.9(3) O8–C8–C14 121.6(3)O8–C8–C7 121.4(3) C14–C8–C7 117.0(2)C10–C9–C14 110.6(2) C10–C9–C19 111.1(2)C14–C9–C19 111.6(2) C11–C10–C1 118.8(2)C11–C10–C9 122.2(2) C1–C10–C9 119.0(2)C10–C11–N12 121.2(2) C10–C11–C4 123.4(2)N12–C11–C4 115.3(2) C11–N12–C13 121.7(2)C14–C13–N12 121.2(2) C14–C13–C5 124.6(2)N12–C13–C5 114.2(2) C13–C14–C8 119.5(2)C13–C14–C9 121.8(2) C8–C14–C9 118.7(2)

in compound 1 and a N–H⋅ ⋅ ⋅O interaction in compound 2,respectively (Table 4).

4. Conclusions

Compounds (1) and (2) were synthesized by adopting multi-component reaction systemand the correspondingmolecularand crystal structures were determined by single crystal

X-ray diffraction. In compound 1 there are two independentmolecules per asymmetric unit.The 1,4-dihydropyridine ringadopts boat conformation in both compounds 1 and 2. Inaddition the cyclohexane rings display sofa conformationsfor both molecules A and B in compound 1 whereas in 2the cyclohexane ring (C5/C6/C7/C8/C14/C13) adopts halfchair conformation and the other ring adopts sofa conforma-tion.

Journal of Crystallography 7

Table 3: Comparison of conformation in the 1,4-dihydropyridine rings.

Compound Conformation Ref.1 Boat This work2 Boat This work3 Boat [9]4 Boat [10]5 Boat [15]6 Boat [16]

Table 4: Hydrogen bond data.

D–H⋅ ⋅ ⋅A D–H (Å) H–A (Å) D–A (Å) D–H⋅ ⋅ ⋅A (∘)Compound 1

C7A–H7A2⋅ ⋅ ⋅O1B 0.97 2.485 3.444 170C2A–H2A1⋅ ⋅ ⋅O25Bi 0.97 2.579 3.503 159N12A–H12A⋅ ⋅ ⋅O8Aii 0.86 2.113 2.882 149C5A–H5A2⋅ ⋅ ⋅O25Aiii 0.97 2.655 3.597 163N12B–H12B⋅ ⋅ ⋅O8Biv 0.86 2.092 2.892 154C7B–H7B2⋅ ⋅ ⋅O1Av 0.97 2.561 3.523 171

Compound 2N12–H12⋅ ⋅ ⋅O1vi 0.86 1.885 2.733(3) 169Symmetry code:i𝑥 − 1, −𝑦 + 1/2 + 2, +𝑧 + 1/2 ii − 𝑥, +𝑦 + 1/2, +𝑧 iii𝑥, −𝑦 + 1/2 + 2, +𝑧 − 1/2 iv − 𝑥 + 1, +𝑦 − 1/2, +𝑧 v𝑥 + 1, +𝑦, +𝑧 vi𝑥 − 1/2, −𝑦 + 1/2, +𝑧.

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper.

Acknowledgment

One of the authors (Rajni Kant) acknowledges the Depart-ment of Science & Technology for sanctioning single crystalX-ray diffractometer as a National Facility under Project no.SR/S2/CMP-47/2003.

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