1-(3-Chloro-4-tolyl)-5-méthylthio-3a-phényl-3a,11-dihydro-4H-[1,2,4]oxadiazolo[5,4-d][1,5]benzodiazépine

El Hazazi, S.; Baouid, A.; Hasnaoui, A.; Pierrot, M.

doi:10.1107/S1600536802006761

1-(3-Chloro-4-tolyl)-5-méthylthio-3a-phényl-3a,11-dihydro-4H-[1,2,4]oxadiazolo[5,4-d][1,5]benzodiazépine

S. El Hazazi, A. Baouid, A. Hasnaoui et M. Pierrot

The X-ray crystallographic study of the title compound, C₂₄H₂₀ClN₃OS, clearly demonstrates that 1,3-dipolar cycloaddition occurs at the C=N double bond of the 1,5-benzodiazepine.

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Supporting information

	Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536802006761/dn6029sup1.cif Contains datablocks global, I
	Structure factor file (CIF format) https://doi.org/10.1107/S1600536802006761/dn6029Isup2.hkl Contains datablock I

CCDC reference: 185794

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Key indicators

Single-crystal X-ray study
T = 293 K
Mean (C-C) = 0.004 Å
R factor = 0.067
wR factor = 0.130
Data-to-parameter ratio = 16.0

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No syntax errors found

ADDSYM reports no extra symmetry


 Alert Level C:



CRYSC_01  Alert C The word below has not been recognised as a standard
          identifier.
          incolore

CRYSC_01  Alert C No recognised colour has been given for crystal colour.


 0 Alert Level A = Potentially serious problem

 0 Alert Level B = Potential problem

 2 Alert Level C = Please check

Comment top

Il a été montré que l'addition d'un nouvel hétérocycle, ou de plusieurs, à un hétérocycle azoté à sept chaînons augmente notablement l'activité biologique du composé synthétisé (Bartsch & Erker, 1988; Bellantuono et al., 1980). Notre équipe possède une longue expérience de la synthèse de ce type de molécules (Baouid et al., 1996, 2000; El Hazazi et al., 2000; Benelbaghdadi et al., 1998; Hasnaoui et al., 1991) ayant des structures homologues à celles des composés biologiquement actifs. Nous rapportons ici le comportement du chlorure d'arylcarbohydroxamoyle (Liu et al., 1980; Grundmann & Dean, 1965) en présence de la triéthylamine vis à vis de la 2-méthylthio-4-phényl-3H-[1,5]benzodiazépine (Cortès et al., 1991; Nardi et al., 1973). Cette réaction de condensation dipolaire conduit à un seul monocycloadduit. Les données spectrales de RMN ¹H et ¹³C et de spectroscopie de masse du produit synthétisé nous indiquent qu'on a réalisé une monocondensation résultant de l'addition du dipôle sur l'une des deux doubles liaisons C2—N1 ou C6—N7, mais ces analyses spectrales ne nous permettent pas de distinguer les deux structures isomères du cycloadduit. Une étude cristallographique du monocristal préparé à partir du cycloadduit obtenu nous a conduit à la structure exacte du produit obtenu. Celui-ci résulte de l'addition du dipôle sur la double liaison C6—N7 substituée par le groupement phényle pour aboutir au 1-(3-chloro-4-tolyl)-5-méthylthio-3a-phényl-3a,11-dihydro-4H- [1,2,4]oxadiazolo[5,4-d][1,5]benzodiazépine, [composé (I)]. Par conséquent, on peut conclure que cette réaction de cycloaddition dipolaire-1,3 e s t totalement péri et régiosélective puisque la condensation a été effectuée sur la double liaison C6—N7 substituée par le groupement phényle et non plus sur la double liaison C2—N1 substituée par le groupement méthylthio quelque soit la quantité du dipôle utilisée. Le sens de l'addition est unique car le pôle négatif du dipôle est lié au carbone C6 du site dipolarophile et le pôle positif est lié à l'azote N7. Le coeur de la molécule est composé du tricycle formé par la benzodiazépine et le cycle oxazodiazolo et sur lequel sont fixés les cycles phényl et chlorotosyl et le bras méthylthio. Le cycle à 7 chaînons comporte un fragment plan N7/C8/C13/N14 (déviation standard: 0,004 Å), coplanaire avec le cycle C8–C13 (déviation standard: 0,017 Å) et un fragment gauche décrit par les deux angles de torsion N14—C4—C5—C6 [46,5(3)°] et C4—C5—C6—N7 [-73.7 (3)°]. Le cycle oxazodiazolo présente une conformation enveloppe, l'atome C4 est situé à -0,226 (4) Å du plan C1/N2/O3/N14 (déviation standard: 0,011 Å) contenant la double liaison C1—N2 [1.282 (3) Å]. Le bras méthylthio est situé dans le plan de la double liaison C6—N7: déviation standard du plan C5/C6/N7/C8/S29/C30: 0.015 Å.

Experimental top

A une solution bien agitée de la 2-méthylthio-4-phényl-3H-[1,5]benzodiazépine (0.5 g, 1.88 mmol) dans 5 ml du chloroforme, on ajoute lentement une solution de triéthylamine (3.76 mmol) contenue dans 3 ml du même solvant. Le mélange est porté à reflux sous atmosphère d'azote. Après 45 min, une solution de chlorure d'arylcarbohydroxamoyle (0.77 g, 3.76 mmol) dans 5 ml de chlorofome est ajoutée lentement. Le mélange réactionnel est agité à reflux pendant 24 h. Après refroidissement à température ambiante et traitement du mélange réactionnel, le résidu obtenu est chromatographié sur gel de silice avec un gradient d'éluant hexane–acétate d'éthyle (95:5). Le produit purifié est recristallisé dans l'hexane-dichlorométhane (9:1) pour conduire au composé étudié. P·F. = 431–433 K.

Computing details top

Data collection: KappaCCD Reference Manual (Nonius, 1998); data reduction: DENZO (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEPIII (Burnett & Johnson,1996); software used to prepare material for publication: SHELXL97.

Figures top

Fig. 1. Dessin ORTEPIII (Burnett & Johnson, 1996) de la molécule. Les ellipsoides de vibration des atomes ont une probabilité de 50%.

1-(3-Chloro-4-tolyl)-5-méthylthio-3a-phényl-3a,11-dihydro-4H-[1,2,4] oxadiazolo[5,4-d][1,5]benzodiazépine top

Crystal data top

C₂₄H₂₀ClN₃OS	F(000) = 904
M_r = 433.94	D_x = 1.355 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2yn	Cell parameters from 15172 reflections
a = 8.6890 (4) Å	θ = 2.6–26.5°
b = 18.8253 (9) Å	µ = 0.30 mm⁻¹
c = 13.3728 (7) Å	T = 293 K
β = 103.470 (3)°	Plaquette, incolore
V = 2127.3 (2) Å³	0.30 × 0.15 × 0.08 mm
Z = 4

Data collection top

Nonius KappaCCD diffractometer	3328 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	R_int = 0.071
Graphite monochromator	θ_max = 26.5°, θ_min = 2.6°
ϕ scans	h = −6→10
15172 measured reflections	k = −8→23
4363 independent reflections	l = −16→16

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.067	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.130	H-atom parameters constrained
S = 1.11	w = 1/[σ²(F_o²) + (0.0156P)² + 2.3746P] where P = (F_o² + 2F_c²)/3
4363 reflections	(Δ/σ)_max = 0.002
273 parameters	Δρ_max = 0.21 e Å⁻³
0 restraints	Δρ_min = −0.50 e Å⁻³

Crystal data top

C₂₄H₂₀ClN₃OS	V = 2127.3 (2) Å³
M_r = 433.94	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 8.6890 (4) Å	µ = 0.30 mm⁻¹
b = 18.8253 (9) Å	T = 293 K
c = 13.3728 (7) Å	0.30 × 0.15 × 0.08 mm
β = 103.470 (3)°

Data collection top

Nonius KappaCCD diffractometer	3328 reflections with I > 2σ(I)
15172 measured reflections	R_int = 0.071
4363 independent reflections

Refinement top

R[F² > 2σ(F²)] = 0.067	0 restraints
wR(F²) = 0.130	H-atom parameters constrained
S = 1.11	Δρ_max = 0.21 e Å⁻³
4363 reflections	Δρ_min = −0.50 e Å⁻³
273 parameters

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

	x	y	z	U_iso*/U_eq
Cl21	0.39539 (16)	0.09042 (6)	0.28030 (11)	0.1103 (5)
S29	0.59974 (11)	0.38304 (5)	−0.01191 (6)	0.0567 (3)
O3	0.4435 (2)	0.43868 (10)	0.19588 (15)	0.0417 (5)
N2	0.4347 (3)	0.36584 (11)	0.22417 (18)	0.0380 (5)
N7	0.8168 (3)	0.35223 (12)	0.15741 (17)	0.0371 (5)
N14	0.6693 (2)	0.40861 (10)	0.31285 (16)	0.0304 (5)
C1	0.5658 (3)	0.35152 (13)	0.2878 (2)	0.0319 (6)
C4	0.6010 (3)	0.46516 (13)	0.23785 (19)	0.0330 (6)
C5	0.6903 (3)	0.47009 (14)	0.1526 (2)	0.0379 (6)
H5A	0.6306	0.4994	0.0973	0.046*
H5B	0.7918	0.4928	0.1792	0.046*
C6	0.7168 (3)	0.39806 (14)	0.1106 (2)	0.0363 (6)
C8	0.9066 (3)	0.37064 (13)	0.2564 (2)	0.0332 (6)
C9	1.0693 (3)	0.35951 (16)	0.2795 (2)	0.0434 (7)
H9	1.1164	0.3392	0.2307	0.052*
C10	1.1609 (3)	0.37824 (17)	0.3739 (3)	0.0494 (8)
H10	1.2697	0.3710	0.3882	0.059*
C11	1.0936 (3)	0.40755 (16)	0.4475 (2)	0.0484 (8)
H11	1.1568	0.4207	0.5109	0.058*
C12	0.9318 (3)	0.41755 (14)	0.4273 (2)	0.0386 (6)
H12	0.8859	0.4370	0.4773	0.046*
C13	0.8381 (3)	0.39865 (13)	0.33255 (19)	0.0307 (6)
C15	0.5904 (3)	0.28129 (13)	0.3384 (2)	0.0329 (6)
C16	0.6910 (3)	0.27090 (14)	0.4338 (2)	0.0396 (6)
H16	0.7556	0.3078	0.4652	0.048*
C17	0.6964 (4)	0.20602 (15)	0.4828 (2)	0.0430 (7)
H17	0.7652	0.2003	0.5469	0.052*
C18	0.6035 (3)	0.14955 (14)	0.4401 (2)	0.0419 (7)
C19	0.5088 (4)	0.16013 (15)	0.3425 (3)	0.0510 (8)
C20	0.5013 (4)	0.22420 (15)	0.2921 (2)	0.0479 (7)
H20	0.4362	0.2291	0.2266	0.057*
C22	0.6040 (4)	0.08160 (16)	0.4987 (3)	0.0562 (8)
H22A	0.7011	0.0778	0.5502	0.084*
H22B	0.5948	0.0421	0.4523	0.084*
H22C	0.5163	0.0814	0.5311	0.084*
C23	0.5845 (3)	0.53579 (14)	0.2897 (2)	0.0352 (6)
C24	0.4984 (4)	0.53763 (17)	0.3648 (2)	0.0486 (7)
H24	0.4560	0.4959	0.3840	0.058*
C25	0.4751 (4)	0.60060 (18)	0.4111 (3)	0.0579 (9)
H25	0.4174	0.6010	0.4616	0.069*
C26	0.5363 (4)	0.66296 (17)	0.3834 (3)	0.0576 (9)
H26	0.5191	0.7055	0.4144	0.069*
C27	0.6220 (4)	0.66184 (16)	0.3104 (3)	0.0571 (9)
H27	0.6644	0.7038	0.2917	0.068*
C28	0.6467 (4)	0.59843 (15)	0.2634 (2)	0.0470 (7)
H28	0.7059	0.5983	0.2138	0.056*
C30	0.6518 (5)	0.2944 (2)	−0.0390 (3)	0.0753 (12)
H30A	0.7637	0.2917	−0.0337	0.113*
H30B	0.5962	0.2815	−0.1074	0.113*
H30C	0.6233	0.2623	0.0094	0.113*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
Cl21	0.1182 (10)	0.0566 (6)	0.1231 (10)	−0.0409 (6)	−0.0391 (8)	0.0080 (6)
S29	0.0687 (6)	0.0550 (5)	0.0365 (4)	0.0190 (4)	−0.0076 (4)	−0.0069 (4)
O3	0.0336 (10)	0.0346 (10)	0.0495 (12)	0.0008 (8)	−0.0054 (9)	0.0037 (9)
N2	0.0325 (12)	0.0331 (12)	0.0463 (14)	−0.0003 (10)	0.0046 (10)	0.0004 (10)
N7	0.0393 (12)	0.0369 (12)	0.0343 (12)	0.0059 (10)	0.0068 (10)	0.0004 (10)
N14	0.0302 (11)	0.0253 (10)	0.0341 (11)	−0.0006 (9)	0.0043 (9)	0.0035 (9)
C1	0.0303 (13)	0.0326 (13)	0.0336 (14)	0.0001 (11)	0.0089 (11)	−0.0012 (11)
C4	0.0324 (13)	0.0298 (13)	0.0336 (14)	0.0013 (11)	0.0010 (11)	0.0027 (11)
C5	0.0462 (16)	0.0313 (14)	0.0337 (14)	0.0045 (12)	0.0042 (12)	0.0039 (11)
C6	0.0401 (15)	0.0386 (15)	0.0293 (13)	0.0027 (12)	0.0060 (11)	0.0032 (11)
C8	0.0327 (13)	0.0297 (13)	0.0359 (14)	0.0010 (11)	0.0051 (11)	0.0060 (11)
C9	0.0335 (14)	0.0484 (17)	0.0489 (17)	0.0033 (13)	0.0109 (13)	0.0075 (14)
C10	0.0272 (14)	0.0581 (19)	0.059 (2)	−0.0026 (14)	0.0020 (13)	0.0103 (16)
C11	0.0382 (16)	0.0507 (18)	0.0475 (17)	−0.0083 (14)	−0.0074 (13)	0.0004 (14)
C12	0.0402 (15)	0.0376 (15)	0.0359 (14)	−0.0033 (12)	0.0045 (12)	0.0009 (12)
C13	0.0278 (13)	0.0274 (13)	0.0347 (14)	−0.0016 (10)	0.0027 (11)	0.0060 (10)
C15	0.0328 (13)	0.0297 (13)	0.0389 (15)	−0.0013 (11)	0.0141 (11)	−0.0004 (11)
C16	0.0449 (16)	0.0322 (14)	0.0411 (16)	−0.0054 (12)	0.0084 (13)	−0.0010 (12)
C17	0.0494 (17)	0.0402 (16)	0.0390 (16)	0.0014 (13)	0.0095 (13)	0.0036 (13)
C18	0.0440 (16)	0.0330 (14)	0.0526 (18)	−0.0002 (13)	0.0193 (14)	0.0032 (13)
C19	0.0466 (17)	0.0353 (15)	0.067 (2)	−0.0121 (13)	0.0052 (16)	−0.0010 (15)
C20	0.0469 (17)	0.0404 (16)	0.0496 (18)	−0.0054 (14)	−0.0024 (14)	0.0026 (14)
C22	0.070 (2)	0.0375 (16)	0.065 (2)	−0.0034 (16)	0.0246 (18)	0.0087 (15)
C23	0.0353 (14)	0.0323 (14)	0.0339 (14)	0.0057 (11)	−0.0001 (11)	0.0003 (11)
C24	0.0457 (17)	0.0457 (17)	0.0558 (19)	0.0005 (14)	0.0144 (15)	−0.0046 (15)
C25	0.0528 (19)	0.061 (2)	0.063 (2)	0.0091 (16)	0.0183 (17)	−0.0167 (17)
C26	0.061 (2)	0.0431 (18)	0.061 (2)	0.0130 (16)	−0.0018 (17)	−0.0164 (16)
C27	0.075 (2)	0.0323 (16)	0.058 (2)	−0.0004 (15)	0.0036 (18)	−0.0022 (14)
C28	0.0616 (19)	0.0350 (15)	0.0444 (17)	0.0006 (14)	0.0119 (15)	0.0003 (13)
C30	0.090 (3)	0.063 (2)	0.062 (2)	0.020 (2)	−0.005 (2)	−0.0243 (19)

Geometric parameters (Å, º) top

Cl21—C19	1.733 (3)	C15—C16	1.382 (4)
S29—C6	1.738 (3)	C15—C20	1.384 (4)
S29—C30	1.789 (3)	C16—C17	1.382 (4)
O3—N2	1.429 (3)	C16—H16	0.9300
O3—C4	1.442 (3)	C17—C18	1.376 (4)
N2—C1	1.282 (3)	C17—H17	0.9300
N7—C6	1.280 (3)	C18—C19	1.385 (4)
N7—C8	1.414 (3)	C18—C22	1.500 (4)
N14—C1	1.391 (3)	C19—C20	1.376 (4)
N14—C13	1.441 (3)	C20—H20	0.9300
N14—C4	1.488 (3)	C22—H22A	0.9600
C1—C15	1.478 (3)	C22—H22B	0.9600
C4—C23	1.521 (4)	C22—H22C	0.9600
C4—C5	1.525 (4)	C23—C28	1.376 (4)
C5—C6	1.506 (4)	C23—C24	1.385 (4)
C5—H5A	0.9700	C24—C25	1.374 (4)
C5—H5B	0.9700	C24—H24	0.9300
C8—C9	1.390 (4)	C25—C26	1.375 (5)
C8—C13	1.397 (4)	C25—H25	0.9300
C9—C10	1.372 (4)	C26—C27	1.360 (5)
C9—H9	0.9300	C26—H26	0.9300
C10—C11	1.372 (5)	C27—C28	1.389 (4)
C10—H10	0.9300	C27—H27	0.9300
C11—C12	1.380 (4)	C28—H28	0.9300
C11—H11	0.9300	C30—H30A	0.9600
C12—C13	1.383 (4)	C30—H30B	0.9600
C12—H12	0.9300	C30—H30C	0.9600

C6—S29—C30	102.88 (15)	C15—C16—C17	120.5 (3)
N2—O3—C4	109.46 (17)	C15—C16—H16	119.8
C1—N2—O3	106.5 (2)	C17—C16—H16	119.8
C6—N7—C8	117.2 (2)	C18—C17—C16	122.3 (3)
C1—N14—C13	121.1 (2)	C18—C17—H17	118.9
C1—N14—C4	104.85 (19)	C16—C17—H17	118.9
C13—N14—C4	116.46 (19)	C17—C18—C19	116.3 (3)
N2—C1—N14	115.0 (2)	C17—C18—C22	120.8 (3)
N2—C1—C15	120.2 (2)	C19—C18—C22	122.9 (3)
N14—C1—C15	124.3 (2)	C20—C19—C18	122.5 (3)
O3—C4—N14	102.03 (19)	C20—C19—Cl21	118.1 (2)
O3—C4—C23	107.3 (2)	C18—C19—Cl21	119.3 (2)
N14—C4—C23	112.5 (2)	C19—C20—C15	120.2 (3)
O3—C4—C5	109.4 (2)	C19—C20—H20	119.9
N14—C4—C5	110.8 (2)	C15—C20—H20	119.9
C23—C4—C5	114.0 (2)	C18—C22—H22A	109.5
C6—C5—C4	111.9 (2)	C18—C22—H22B	109.5
C6—C5—H5A	109.2	H22A—C22—H22B	109.5
C4—C5—H5A	109.2	C18—C22—H22C	109.5
C6—C5—H5B	109.2	H22A—C22—H22C	109.5
C4—C5—H5B	109.2	H22B—C22—H22C	109.5
H5A—C5—H5B	107.9	C28—C23—C24	118.3 (3)
N7—C6—C5	124.7 (2)	C28—C23—C4	123.2 (3)
N7—C6—S29	122.2 (2)	C24—C23—C4	118.4 (2)
C5—C6—S29	113.02 (19)	C25—C24—C23	120.6 (3)
C9—C8—C13	118.5 (2)	C25—C24—H24	119.7
C9—C8—N7	118.9 (3)	C23—C24—H24	119.7
C13—C8—N7	122.6 (2)	C24—C25—C26	120.6 (3)
C10—C9—C8	120.5 (3)	C24—C25—H25	119.7
C10—C9—H9	119.7	C26—C25—H25	119.7
C8—C9—H9	119.7	C27—C26—C25	119.4 (3)
C11—C10—C9	120.7 (3)	C27—C26—H26	120.3
C11—C10—H10	119.7	C25—C26—H26	120.3
C9—C10—H10	119.7	C26—C27—C28	120.4 (3)
C10—C11—C12	119.9 (3)	C26—C27—H27	119.8
C10—C11—H11	120.0	C28—C27—H27	119.8
C12—C11—H11	120.0	C23—C28—C27	120.7 (3)
C11—C12—C13	120.0 (3)	C23—C28—H28	119.7
C11—C12—H12	120.0	C27—C28—H28	119.7
C13—C12—H12	120.0	S29—C30—H30A	109.5
C12—C13—C8	120.3 (2)	S29—C30—H30B	109.5
C12—C13—N14	119.4 (2)	H30A—C30—H30B	109.5
C8—C13—N14	120.3 (2)	S29—C30—H30C	109.5
C16—C15—C20	118.1 (2)	H30A—C30—H30C	109.5
C16—C15—C1	122.8 (2)	H30B—C30—H30C	109.5
C20—C15—C1	118.9 (2)

N14—C4—C5—C6	46.5 (3)	C4—C5—C6—N7	−73.7 (3)

Experimental details

Crystal data
Chemical formula	C₂₄H₂₀ClN₃OS
M_r	433.94
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	293
a, b, c (Å)	8.6890 (4), 18.8253 (9), 13.3728 (7)
β (°)	103.470 (3)
V (Å³)	2127.3 (2)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.30
Crystal size (mm)	0.30 × 0.15 × 0.08

Data collection
Diffractometer	Nonius KappaCCD diffractometer
Absorption correction	–
No. of measured, independent and observed [I > 2σ(I)] reflections	15172, 4363, 3328
R_int	0.071
(sin θ/λ)_max (Å⁻¹)	0.628

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.067, 0.130, 1.11
No. of reflections	4363
No. of parameters	273
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.21, −0.50

Computer programs: KappaCCD Reference Manual (Nonius, 1998), DENZO (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1994), SHELXL97 (Sheldrick, 1997), ORTEPIII (Burnett & Johnson,1996), SHELXL97.

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