3,4-Dimethyl-1H-1,2,4-triazepino[2,3-a]benzimidazol-2(3H)-one.

In the mol-ecule of the title compound, C(12)H(12)N(4)O, a C atom and an N atom of the benzimidazole fused-ring portion are part of a seven-membered ring; this ring adopts a boat-shaped conformation (with the fused-ring atoms representing the stern and the sp(3)-hybridized C atom the prow). The amino group is a hydrogen-bond donor to the imidazole group of an inversion-related mol-ecule, the pair of N-H⋯N hydrogen bonds giving rise to a hydrogen-bonded dimer.

Related literature

For the synthesis, see: Romano et al. (1988 ▶).

Experimental

Crystal data

C12<span class="Species">H12N4O

M = 228.26

Monoclinic,

a = 7.2899 (3) Å

b = 14.4888 (5) Å

c = 10.9932 (4) Å

β = 104.314 (1)°

V = 1125.08 (7) Å3

Z = 4

Mo Kα radiation

μ = 0.09 mm−1

T = 293 K

0.21 × 0.19 × 0.16 mm

Data collection

Bruker X8 APEXII diffractometer

14670 measured reflections

3095 independent reflections

1823 reflections with I > 2σ(I)

R int = 0.034

Refinement

R[F 2 > 2σ(F 2)] = 0.049

wR(F 2) = 0.157

S = 1.01

3095 reflections

160 parameters

1 restraint

<span class="Disease">H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.24 e Å−3

Δρmin = −0.19 e Å−3

Data collection: APEX2 (Bruker, 2008 ▶); cell refinement: SAINT (Bruker, 2008 ▶); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: X-SEED (Barbour, 2001 ▶); software used to prepare material for publication: publCIF (Westrip, 2010 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810013498/si2255sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810013498/si2255Isup2.hkl

Additional supplementary materials: crystallographic information; 3D view; checkCIF report

C12H12N4O	F(000) = 480
Mr = 228.26	Dx = 1.348 Mg m−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3188 reflections
a = 7.2899 (3) Å	θ = 2.4–24.8°
b = 14.4888 (5) Å	µ = 0.09 mm−1
c = 10.9932 (4) Å	T = 293 K
β = 104.314 (1)°	Prism, brown
V = 1125.08 (7) Å3	0.21 × 0.19 × 0.16 mm
Z = 4

Bruker X8 APEXII diffractometer	1823 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.034
graphite	θmax = 29.4°, θmin = 2.4°
φ and ω scans	h = −9→10
14670 measured reflections	k = −20→19
3095 independent reflections	l = −15→13

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)] = 0.049	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.157	H atoms treated by a mixture of independent and constrained refinement
S = 1.01	w = 1/[σ2(Fo2) + (0.0742P)2 + 0.1838P] where P = (Fo2 + 2Fc2)/3
3095 reflections	(Δ/σ)max < 0.001
160 parameters	Δρmax = 0.24 e Å−3
1 restraint	Δρmin = −0.19 e Å−3

	x	y	z	Uiso*/Ueq
O1	0.40956 (19)	0.51793 (12)	0.14398 (13)	0.0762 (5)
N1	0.5626 (2)	0.53766 (12)	0.34574 (15)	0.0574 (4)
H1	0.486 (3)	0.5002 (13)	0.3696 (19)	0.075 (7)*
N2	0.95622 (19)	0.59291 (9)	0.32932 (14)	0.0508 (4)
N3	0.86966 (19)	0.60627 (9)	0.42759 (13)	0.0475 (4)
N4	0.6799 (2)	0.58224 (10)	0.55706 (13)	0.0552 (4)
C1	0.6977 (2)	0.57641 (11)	0.44172 (16)	0.0488 (4)
C2	0.5294 (2)	0.55903 (14)	0.22125 (17)	0.0569 (5)
C3	0.6491 (2)	0.63705 (13)	0.18892 (16)	0.0551 (5)
H3	0.6428	0.6886	0.2454	0.066*
C4	0.8529 (2)	0.60475 (11)	0.21815 (17)	0.0498 (4)
C5	0.5699 (3)	0.67076 (16)	0.05638 (19)	0.0797 (7)
H5A	0.6472	0.7202	0.0387	0.120*
H5B	0.4429	0.6926	0.0475	0.120*
H5C	0.5692	0.6210	−0.0014	0.120*
C6	0.9446 (3)	0.58710 (16)	0.11287 (19)	0.0694 (6)
H6A	1.0719	0.5659	0.1463	0.104*
H6B	0.9466	0.6432	0.0667	0.104*
H6C	0.8742	0.5409	0.0580	0.104*
C7	0.9748 (2)	0.62947 (10)	0.54769 (16)	0.0486 (4)
C8	1.1602 (3)	0.65870 (13)	0.59037 (19)	0.0636 (5)
H8	1.2399	0.6664	0.5369	0.076*
C9	1.2194 (3)	0.67573 (16)	0.7180 (2)	0.0790 (7)
H9	1.3432	0.6950	0.7517	0.095*
C10	1.0993 (4)	0.66492 (16)	0.7969 (2)	0.0780 (7)
H10	1.1444	0.6782	0.8819	0.094*
C11	0.9147 (3)	0.63502 (14)	0.75350 (18)	0.0653 (5)
H11	0.8348	0.6279	0.8070	0.078*
C12	0.8542 (3)	0.61603 (11)	0.62561 (16)	0.0516 (4)

	U11	U22	U33	U12	U13	U23
O1	0.0480 (8)	0.1131 (12)	0.0627 (9)	−0.0193 (7)	0.0049 (6)	−0.0313 (8)
N1	0.0401 (8)	0.0756 (10)	0.0538 (9)	−0.0152 (7)	0.0068 (7)	−0.0171 (7)
N2	0.0385 (7)	0.0536 (8)	0.0580 (9)	−0.0022 (6)	0.0074 (7)	−0.0016 (6)
N3	0.0368 (7)	0.0521 (8)	0.0487 (8)	−0.0038 (6)	0.0012 (6)	−0.0036 (6)
N4	0.0461 (8)	0.0639 (9)	0.0520 (9)	−0.0080 (7)	0.0055 (7)	−0.0121 (7)
C1	0.0378 (8)	0.0540 (9)	0.0505 (9)	−0.0027 (7)	0.0035 (7)	−0.0103 (7)
C2	0.0349 (9)	0.0763 (12)	0.0565 (10)	0.0011 (8)	0.0056 (8)	−0.0202 (9)
C3	0.0468 (10)	0.0591 (10)	0.0536 (10)	0.0051 (8)	0.0014 (8)	−0.0080 (8)
C4	0.0404 (9)	0.0497 (9)	0.0563 (10)	−0.0035 (7)	0.0066 (8)	−0.0038 (7)
C5	0.0758 (15)	0.0797 (14)	0.0688 (13)	0.0114 (11)	−0.0103 (11)	−0.0030 (11)
C6	0.0578 (12)	0.0891 (15)	0.0640 (12)	−0.0009 (10)	0.0202 (10)	−0.0015 (10)
C7	0.0439 (9)	0.0417 (8)	0.0517 (9)	−0.0036 (7)	−0.0045 (8)	0.0010 (7)
C8	0.0482 (10)	0.0662 (11)	0.0657 (11)	−0.0128 (8)	−0.0065 (9)	0.0088 (9)
C9	0.0628 (13)	0.0825 (14)	0.0724 (14)	−0.0247 (11)	−0.0200 (11)	0.0067 (11)
C10	0.0816 (16)	0.0786 (14)	0.0575 (12)	−0.0199 (11)	−0.0137 (11)	−0.0014 (10)
C11	0.0708 (13)	0.0655 (11)	0.0521 (10)	−0.0082 (10)	0.0009 (9)	−0.0061 (8)
C12	0.0501 (10)	0.0467 (9)	0.0507 (9)	−0.0036 (7)	−0.0012 (8)	−0.0047 (7)

O1—C2	1.213 (2)	C5—H5B	0.9600
N1—C2	1.365 (2)	C5—H5C	0.9600
N1—C1	1.373 (2)	C6—H6A	0.9600
N1—H1	0.864 (9)	C6—H6B	0.9600
N2—C4	1.279 (2)	C6—H6C	0.9600
N2—N3	1.393 (2)	C7—C8	1.383 (2)
N3—C1	1.371 (2)	C7—C12	1.385 (3)
N3—C7	1.394 (2)	C8—C9	1.384 (3)
N4—C1	1.309 (2)	C8—H8	0.9300
N4—C12	1.396 (2)	C9—C10	1.386 (3)
C2—C3	1.523 (3)	C9—H9	0.9300
C3—C5	1.510 (3)	C10—C11	1.382 (3)
C3—C4	1.515 (2)	C10—H10	0.9300
C3—H3	0.9800	C11—C12	1.393 (2)
C4—C6	1.495 (3)	C11—H11	0.9300
C5—H5A	0.9600
C2—N1—C1	126.41 (17)	H5A—C5—H5C	109.5
C2—N1—H1	118.6 (14)	H5B—C5—H5C	109.5
C1—N1—H1	114.7 (14)	C4—C6—H6A	109.5
C4—N2—N3	116.74 (14)	C4—C6—H6B	109.5
C1—N3—N2	130.27 (13)	H6A—C6—H6B	109.5
C1—N3—C7	105.84 (14)	C4—C6—H6C	109.5
N2—N3—C7	121.30 (14)	H6A—C6—H6C	109.5
C1—N4—C12	104.53 (15)	H6B—C6—H6C	109.5
N4—C1—N3	113.68 (14)	C8—C7—C12	123.37 (17)
N4—C1—N1	123.18 (16)	C8—C7—N3	131.12 (19)
N3—C1—N1	122.98 (16)	C12—C7—N3	105.50 (14)
O1—C2—N1	120.60 (19)	C7—C8—C9	115.6 (2)
O1—C2—C3	123.76 (18)	C7—C8—H8	122.2
N1—C2—C3	115.63 (14)	C9—C8—H8	122.2
C5—C3—C4	115.20 (18)	C8—C9—C10	121.89 (19)
C5—C3—C2	111.16 (15)	C8—C9—H9	119.1
C4—C3—C2	108.05 (14)	C10—C9—H9	119.1
C5—C3—H3	107.4	C11—C10—C9	122.06 (19)
C4—C3—H3	107.4	C11—C10—H10	119.0
C2—C3—H3	107.4	C9—C10—H10	119.0
N2—C4—C6	116.53 (16)	C10—C11—C12	116.7 (2)
N2—C4—C3	124.01 (16)	C10—C11—H11	121.7
C6—C4—C3	119.45 (16)	C12—C11—H11	121.7
C3—C5—H5A	109.5	C7—C12—C11	120.37 (17)
C3—C5—H5B	109.5	C7—C12—N4	110.36 (15)
H5A—C5—H5B	109.5	C11—C12—N4	129.27 (19)
C3—C5—H5C	109.5
C4—N2—N3—C1	45.3 (2)	C5—C3—C4—C6	−14.2 (2)
C4—N2—N3—C7	−155.63 (15)	C2—C3—C4—C6	110.73 (19)
C12—N4—C1—N3	−1.68 (19)	C1—N3—C7—C8	176.13 (18)
C12—N4—C1—N1	173.69 (17)	N2—N3—C7—C8	12.6 (3)
N2—N3—C1—N4	164.44 (16)	C1—N3—C7—C12	−2.84 (17)
C7—N3—C1—N4	2.94 (19)	N2—N3—C7—C12	−166.39 (14)
N2—N3—C1—N1	−10.9 (3)	C12—C7—C8—C9	−1.1 (3)
C7—N3—C1—N1	−172.44 (16)	N3—C7—C8—C9	−179.90 (18)
C2—N1—C1—N4	152.30 (18)	C7—C8—C9—C10	−0.6 (3)
C2—N1—C1—N3	−32.8 (3)	C8—C9—C10—C11	1.2 (4)
C1—N1—C2—O1	177.59 (18)	C9—C10—C11—C12	0.0 (3)
C1—N1—C2—C3	−3.3 (3)	C8—C7—C12—C11	2.3 (3)
O1—C2—C3—C5	13.2 (3)	N3—C7—C12—C11	−178.66 (16)
N1—C2—C3—C5	−165.91 (17)	C8—C7—C12—N4	−177.09 (16)
O1—C2—C3—C4	−114.2 (2)	N3—C7—C12—N4	1.99 (18)
N1—C2—C3—C4	66.8 (2)	C10—C11—C12—C7	−1.6 (3)
N3—N2—C4—C6	−177.91 (15)	C10—C11—C12—N4	177.58 (18)
N3—N2—C4—C3	3.5 (2)	C1—N4—C12—C7	−0.27 (19)
C5—C3—C4—N2	164.30 (17)	C1—N4—C12—C11	−179.55 (19)
C2—C3—C4—N2	−70.7 (2)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···N4i	0.86 (1)	2.01 (1)	2.867 (2)	174 (2)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N1—H1⋯N4i	0.86 (1)	2.01 (1)	2.867 (2)	174 (2)

Symmetry code: (i) .