Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536803013618/dn6079sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536803013618/dn6079Isup2.hkl |
CCDC reference: 217605
A mixture of N,N-dibutyl-4-iodoaniline (1.3 g, 3.93 mmol), chloroform (2.5 ml), methanol (2.5 ml) and hydrogen peroxide (35% w/w in water, 2.5 ml) was heated to reflux. Starting material was still present after 24 h, as shown by thin-layer chromatography (silica), 9:1 60–80 petroleum ether–DCM, RF = 0.78). Further additions of hydrogen peroxide (35% w/w in water, 2.5 ml) were made every 24 h for 4 d until the starting material had been consumed. The product was then isolated by extraction into chloroform followed by crystallization (DCM/60–80 petroleum ether) to give colourless crystals (180 mg, 10%). M.p. 471 K. Crystals were grown by slow evaporation of a solution in CDCl3. (λmax (CH2Cl2)/nm log (ε): 239 (4.08), 343 (4.13) m/z (TOF MS ES+): 454.54 ([M + 4H]+), 330.07 ([M - I + 4H]+, 100%), 327.17 ([M - I + H]+), 217.01 ([M - IC6H4NO]+), 201.07 ([M - I + 3H]+).
H atoms placed geometrically after each cycle The structure was solved for the major component using SIR97 (Altomare et al., 1994). The disorder was detected through the large anisotropic displacement parameters (ADPs) and a residual peak near nitrogen of 2 e Å−3. Because of the severe disorder, the structure was refined with similarity restraints between the two N2O residues. The phenyl groups were refined with hexagonally restrained geometry and ADP similarity restraints. Almost-coincident atoms were restrained to have similar ADPs. The larges residual peak in the difference map was close to iodine. with a smaller peak near the disordered N2O. The reflection 004 has Fc = 68.5, Fo = −0.45, and was omitted from the refinement. After averaging Friedel pairs there would be 1556 unique reflections.
Data collection: COLLECT (Nonius BV, 1997–2001); cell refinement: DENZO and SCALEPACK; data reduction: DENZO and SCALEPACK (Otwinowski & Minor, 1996); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: CRYSTALS (Watkin et al., 2001); molecular graphics: CAMERON; software used to prepare material for publication: CRYSTALS.
C12H8I2N2O | Dx = 2.337 Mg m−3 |
Mr = 450.02 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, I2cb | Cell parameters from 1542 reflections |
a = 6.0119 (1) Å | θ = 1–27° |
b = 7.2082 (2) Å | µ = 4.90 mm−1 |
c = 59.0233 (18) Å | T = 150 K |
V = 2557.77 (11) Å3 | Plate, white |
Z = 8 | 0.20 × 0.19 × 0.01 mm |
F(000) = 1663.999 |
Nonius KappaCCD diffractometer | 2681 reflections with I > −10.00u(I) |
Graphite monochromator | Rint = 0.00 |
ω scans | θmax = 27.5°, θmin = 1.4° |
Absorption correction: multi-scan (DENZO and SCALEPACK; Otwinowski & Minor, 1996) | h = −7→7 |
Tmin = 0.39, Tmax = 0.95 | k = −9→9 |
2815 measured reflections | l = −74→75 |
2682 independent reflections |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H-atom parameters not refined |
R[F2 > 2σ(F2)] = 0.055 | W = q/[σ2(F) + [P(1)p]2 + P(2)p + P(4) + P(5)Sinθ] |
wR(F2) = 0.105 | (Δ/σ)max = 0.003 |
S = 0.98 | Δρmax = 1.78 e Å−3 |
2681 reflections | Δρmin = −1.70 e Å−3 |
296 parameters | Absolute structure: Flack & Bernadinelli (1999, 2000), 1226 Friedel-pairs |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: 0.46 (9) |
C12H8I2N2O | V = 2557.77 (11) Å3 |
Mr = 450.02 | Z = 8 |
Orthorhombic, I2cb | Mo Kα radiation |
a = 6.0119 (1) Å | µ = 4.90 mm−1 |
b = 7.2082 (2) Å | T = 150 K |
c = 59.0233 (18) Å | 0.20 × 0.19 × 0.01 mm |
Nonius KappaCCD diffractometer | 2682 independent reflections |
Absorption correction: multi-scan (DENZO and SCALEPACK; Otwinowski & Minor, 1996) | 2681 reflections with I > −10.00u(I) |
Tmin = 0.39, Tmax = 0.95 | Rint = 0.00 |
2815 measured reflections |
R[F2 > 2σ(F2)] = 0.055 | H-atom parameters not refined |
wR(F2) = 0.105 | Δρmax = 1.78 e Å−3 |
S = 0.98 | Δρmin = −1.70 e Å−3 |
2681 reflections | Absolute structure: Flack & Bernadinelli (1999, 2000), 1226 Friedel-pairs |
296 parameters | Absolute structure parameter: 0.46 (9) |
x | y | z | Uiso*/Ueq | Occ. (<1) | |
I1 | 0.7945 (13) | 0.2264 (4) | 0.52342 (8) | 0.0512 | 0.802 (8) |
I2 | −0.129 (1) | 0.2883 (2) | 0.72751 (4) | 0.0371 | 0.802 (8) |
C1 | 0.6587 (16) | 0.2379 (9) | 0.55608 (12) | 0.0312 | 0.802 (8) |
C2 | 0.7826 (16) | 0.1710 (9) | 0.57436 (14) | 0.0348 | 0.802 (8) |
C3 | 0.6882 (14) | 0.1798 (8) | 0.59614 (12) | 0.0348 | 0.802 (8) |
C4 | 0.4740 (12) | 0.2548 (8) | 0.59870 (9) | 0.0280 | 0.802 (8) |
C5 | 0.3592 (14) | 0.3208 (8) | 0.58020 (12) | 0.0324 | 0.802 (8) |
C6 | 0.4471 (16) | 0.3125 (9) | 0.55870 (13) | 0.0368 | 0.802 (8) |
C7 | 0.0589 (16) | 0.2680 (8) | 0.69762 (12) | 0.0291 | 0.802 (8) |
C8 | 0.2717 (16) | 0.1925 (9) | 0.69799 (14) | 0.0355 | 0.802 (8) |
C9 | 0.3930 (15) | 0.1755 (9) | 0.67824 (13) | 0.0391 | 0.802 (8) |
C10 | 0.3040 (11) | 0.2337 (7) | 0.65805 (9) | 0.0331 | 0.802 (8) |
C11 | 0.0894 (14) | 0.3111 (8) | 0.65727 (12) | 0.0352 | 0.802 (8) |
C12 | −0.0342 (16) | 0.3277 (9) | 0.67726 (14) | 0.0304 | 0.802 (8) |
N1 | 0.3773 (16) | 0.2668 (8) | 0.62055 (11) | 0.0344 | 0.802 (8) |
N2 | 0.4321 (12) | 0.2134 (9) | 0.63721 (12) | 0.0364 | 0.802 (8) |
O1 | 0.6288 (13) | 0.1353 (9) | 0.64031 (12) | 0.0506 | 0.802 (8) |
I201 | 0.826 (3) | 0.2238 (17) | 0.5215 (4) | 0.0512 | 0.198 (8) |
I202 | −0.0814 (19) | 0.280 (1) | 0.72716 (19) | 0.0371 | 0.198 (8) |
O201 | 0.096 (3) | 0.3700 (17) | 0.6112 (5) | 0.0419 | 0.198 (8) |
N201 | 0.296 (3) | 0.2953 (17) | 0.6130 (3) | 0.0391 | 0.198 (8) |
N202 | 0.344 (4) | 0.255 (2) | 0.6301 (3) | 0.0402 | 0.198 (8) |
C201 | 0.650 (5) | 0.248 (2) | 0.5519 (4) | 0.0333 | 0.198 (8) |
C202 | 0.749 (4) | 0.187 (2) | 0.5719 (5) | 0.0342 | 0.198 (8) |
C203 | 0.630 (3) | 0.2030 (14) | 0.5921 (4) | 0.0342 | 0.198 (8) |
C204 | 0.418 (3) | 0.2796 (13) | 0.5921 (3) | 0.0336 | 0.198 (8) |
C205 | 0.322 (4) | 0.3405 (16) | 0.5720 (3) | 0.0372 | 0.198 (8) |
C206 | 0.438 (5) | 0.325 (2) | 0.5517 (3) | 0.0370 | 0.198 (8) |
C207 | 0.059 (3) | 0.2724 (15) | 0.6949 (3) | 0.0292 | 0.198 (8) |
C208 | 0.271 (3) | 0.1994 (15) | 0.6922 (3) | 0.0336 | 0.198 (8) |
C209 | 0.364 (3) | 0.1938 (15) | 0.6707 (3) | 0.0327 | 0.198 (8) |
C210 | 0.246 (3) | 0.2607 (15) | 0.6522 (3) | 0.0364 | 0.198 (8) |
C211 | 0.032 (3) | 0.3341 (15) | 0.6550 (3) | 0.0327 | 0.198 (8) |
C212 | −0.063 (4) | 0.3400 (16) | 0.6766 (4) | 0.0307 | 0.198 (8) |
H101 | 0.5458 | 0.1208 | 0.6786 | 0.0469* | 0.802 (8) |
H102 | 0.3375 | 0.1503 | 0.7127 | 0.0426* | 0.802 (8) |
H104 | −0.1874 | 0.3817 | 0.6769 | 0.0365* | 0.802 (8) |
H105 | 0.0256 | 0.3540 | 0.6425 | 0.0422* | 0.802 (8) |
H2101 | 0.5164 | 0.1415 | 0.6685 | 0.0392* | 0.198 (8) |
H2102 | 0.3554 | 0.1515 | 0.7056 | 0.0403* | 0.198 (8) |
H2104 | −0.2152 | 0.3920 | 0.6788 | 0.0368* | 0.198 (8) |
H2105 | −0.0519 | 0.3820 | 0.6416 | 0.0393* | 0.198 (8) |
H2041 | 0.6983 | 0.1597 | 0.6066 | 0.0411* | 0.198 (8) |
H2042 | 0.9016 | 0.1318 | 0.5717 | 0.0411* | 0.198 (8) |
H2044 | 0.3697 | 0.3686 | 0.5371 | 0.0444* | 0.198 (8) |
H2045 | 0.1692 | 0.3955 | 0.5721 | 0.0446* | 0.198 (8) |
H41 | 0.7724 | 0.1334 | 0.6096 | 0.0418* | 0.802 (8) |
H42 | 0.9347 | 0.1182 | 0.5720 | 0.0418* | 0.802 (8) |
H44 | 0.3612 | 0.3588 | 0.5453 | 0.0442* | 0.802 (8) |
H45 | 0.2083 | 0.3761 | 0.5824 | 0.0389* | 0.802 (8) |
U11 | U22 | U33 | U12 | U13 | U23 | |
I1 | 0.0700 (16) | 0.0544 (4) | 0.029 (1) | −0.0077 (7) | 0.0141 (7) | −0.0057 (3) |
I2 | 0.0341 (12) | 0.0453 (3) | 0.0320 (3) | −0.0011 (5) | 0.0050 (6) | −0.0012 (3) |
C1 | 0.042 (4) | 0.030 (4) | 0.021 (4) | −0.001 (3) | −0.007 (4) | 0.004 (3) |
C2 | 0.035 (4) | 0.028 (4) | 0.041 (4) | 0.009 (4) | −0.006 (4) | 0.000 (3) |
C3 | 0.043 (5) | 0.028 (4) | 0.034 (4) | 0.007 (4) | −0.010 (4) | 0.008 (3) |
C4 | 0.034 (4) | 0.025 (4) | 0.025 (4) | −0.002 (3) | 0.006 (3) | 0.007 (3) |
C5 | 0.030 (4) | 0.034 (4) | 0.034 (4) | 0.008 (4) | −0.004 (4) | 0.006 (3) |
C6 | 0.041 (4) | 0.040 (5) | 0.030 (5) | 0.001 (4) | −0.003 (4) | 0.015 (4) |
C7 | 0.031 (4) | 0.029 (4) | 0.027 (4) | −0.001 (3) | 0.006 (3) | 0.000 (3) |
C8 | 0.030 (4) | 0.035 (4) | 0.042 (5) | 0.004 (4) | 0.010 (4) | 0.009 (3) |
C9 | 0.043 (5) | 0.029 (4) | 0.045 (4) | 0.002 (4) | 0.006 (4) | 0.011 (4) |
C10 | 0.034 (4) | 0.028 (4) | 0.037 (4) | −0.001 (3) | 0.004 (3) | −0.000 (3) |
C11 | 0.046 (5) | 0.027 (4) | 0.033 (4) | 0.001 (4) | −0.003 (4) | 0.006 (4) |
C12 | 0.027 (4) | 0.024 (4) | 0.040 (4) | 0.005 (3) | −0.002 (3) | −0.001 (3) |
N1 | 0.037 (4) | 0.038 (4) | 0.028 (3) | −0.011 (4) | 0.011 (3) | −0.008 (3) |
N2 | 0.038 (4) | 0.033 (3) | 0.038 (3) | 0.005 (3) | 0.008 (3) | −0.001 (3) |
O1 | 0.048 (4) | 0.063 (5) | 0.040 (4) | 0.027 (4) | 0.003 (3) | −0.001 (3) |
I201 | 0.0700 (16) | 0.0544 (4) | 0.029 (1) | −0.0077 (7) | 0.0141 (7) | −0.0057 (3) |
I202 | 0.0341 (12) | 0.0453 (3) | 0.0320 (3) | −0.0011 (5) | 0.0050 (6) | −0.0012 (3) |
O201 | 0.050 (9) | 0.04 (1) | 0.032 (9) | 0.008 (8) | 0.007 (8) | −0.002 (8) |
N201 | 0.046 (6) | 0.037 (6) | 0.034 (5) | 0.004 (5) | 0.012 (5) | 0.001 (5) |
N202 | 0.042 (6) | 0.040 (6) | 0.039 (6) | 0.009 (5) | 0.006 (5) | −0.007 (6) |
C201 | 0.043 (7) | 0.033 (7) | 0.024 (6) | 0.001 (6) | −0.010 (6) | 0.003 (6) |
C202 | 0.040 (7) | 0.028 (7) | 0.034 (6) | 0.007 (6) | −0.008 (6) | 0.003 (6) |
C203 | 0.047 (7) | 0.027 (7) | 0.029 (7) | 0.005 (7) | −0.011 (6) | 0.015 (7) |
C204 | 0.041 (6) | 0.031 (6) | 0.028 (6) | 0.004 (5) | 0.004 (5) | 0.005 (6) |
C205 | 0.041 (8) | 0.035 (7) | 0.036 (6) | 0.007 (7) | −0.001 (6) | 0.016 (7) |
C206 | 0.043 (7) | 0.038 (7) | 0.030 (6) | 0.002 (7) | −0.004 (7) | 0.015 (7) |
C207 | 0.031 (6) | 0.027 (7) | 0.029 (5) | −0.001 (6) | 0.008 (6) | 0.007 (6) |
C208 | 0.031 (7) | 0.029 (7) | 0.041 (6) | 0.001 (7) | 0.015 (7) | 0.014 (7) |
C209 | 0.04 (1) | 0.02 (1) | 0.035 (8) | 0.00 (1) | 0.016 (8) | 0.017 (9) |
C210 | 0.039 (5) | 0.029 (5) | 0.041 (5) | 0.003 (5) | 0.006 (4) | 0.006 (5) |
C211 | 0.042 (7) | 0.022 (7) | 0.034 (7) | 0.002 (6) | −0.002 (6) | 0.002 (7) |
C212 | 0.029 (6) | 0.026 (7) | 0.037 (6) | 0.005 (6) | −0.001 (6) | 0.003 (6) |
I1—C1 | 2.095 (6) | N201—N202 | 1.090 (9) |
I2—C7 | 2.098 (6) | N201—C204 | 1.438 (9) |
C1—C2 | 1.397 (7) | N202—C210 | 1.433 (9) |
C1—C6 | 1.390 (8) | C201—C202 | 1.391 (9) |
C2—C3 | 1.407 (8) | C201—C206 | 1.393 (9) |
C2—H42 | 1.000 | C202—C203 | 1.396 (9) |
C3—C4 | 1.405 (7) | C202—H2042 | 1.000 |
C3—H41 | 1.000 | C203—C204 | 1.393 (9) |
C4—C5 | 1.377 (7) | C203—H2041 | 1.000 |
C4—N1 | 1.417 (6) | C204—C205 | 1.389 (9) |
C5—C6 | 1.376 (7) | C205—C206 | 1.392 (9) |
C5—H45 | 1.000 | C205—H2045 | 1.000 |
C6—H44 | 1.000 | C206—H2044 | 1.000 |
C7—C8 | 1.391 (8) | C207—C208 | 1.389 (9) |
C7—C12 | 1.394 (8) | C207—C212 | 1.392 (9) |
C8—C9 | 1.380 (8) | C208—C209 | 1.387 (9) |
C8—H102 | 1.000 | C208—H2102 | 1.000 |
C9—C10 | 1.372 (7) | C209—C210 | 1.387 (9) |
C9—H101 | 1.000 | C209—H2101 | 1.000 |
C10—C11 | 1.406 (7) | C210—C211 | 1.398 (9) |
C10—N2 | 1.459 (7) | C211—C212 | 1.393 (9) |
C11—C12 | 1.400 (7) | C211—H2105 | 1.000 |
C11—H105 | 1.000 | C212—H2104 | 1.000 |
C12—H104 | 1.000 | H101—H2101 | 0.642 |
N2—O1 | 1.322 (7) | H102—H2102 | 0.433 |
I201—C201 | 2.088 (9) | H104—H2104 | 0.213 |
I202—C207 | 2.083 (9) | H105—H2105 | 0.510 |
O201—N201 | 1.321 (9) | ||
I1—C1—C2 | 119.3 (6) | O201—N201—C204 | 115.1 (17) |
I1—C1—C6 | 118.3 (6) | N202—N201—C204 | 129.8 (18) |
C2—C1—C6 | 122.4 (7) | N201—N202—C210 | 136.8 (19) |
C1—C2—C3 | 118.4 (7) | I201—C201—C202 | 119 (2) |
C1—C2—H42 | 120.803 | I201—C201—C206 | 119 (2) |
C3—C2—H42 | 120.803 | C202—C201—C206 | 121.8 (13) |
C2—C3—C4 | 119.0 (5) | C201—C202—C203 | 118.7 (12) |
C2—C3—H41 | 120.488 | C201—C202—H2042 | 120.639 |
C4—C3—H41 | 120.488 | C203—C202—H2042 | 120.639 |
C3—C4—C5 | 120.49 (13) | C202—C203—C204 | 120.0 (8) |
C3—C4—N1 | 119.81 (9) | C202—C203—H2041 | 119.986 |
C5—C4—N1 | 119.69 (9) | C204—C203—H2041 | 119.986 |
C4—C5—C6 | 121.6 (5) | N201—C204—C203 | 119.8 (1) |
C4—C5—H45 | 119.197 | N201—C204—C205 | 119.8 (1) |
C6—C5—H45 | 119.197 | C203—C204—C205 | 120.49 (14) |
C1—C6—C5 | 118.1 (7) | C204—C205—C206 | 120.2 (8) |
C1—C6—H44 | 120.954 | C204—C205—H2045 | 119.900 |
C5—C6—H44 | 120.954 | C206—C205—H2045 | 119.900 |
I2—C7—C8 | 120.6 (6) | C201—C206—C205 | 118.8 (12) |
I2—C7—C12 | 119.2 (6) | C201—C206—H2044 | 120.614 |
C8—C7—C12 | 120.2 (7) | C205—C206—H2044 | 120.614 |
C7—C8—C9 | 120.5 (7) | I202—C207—C208 | 119.1 (11) |
C7—C8—H102 | 119.748 | I202—C207—C212 | 119.3 (11) |
C9—C8—H102 | 119.748 | C208—C207—C212 | 121.6 (13) |
C8—C9—C10 | 120.0 (6) | C207—C208—C209 | 119.1 (12) |
C8—C9—H101 | 119.985 | C207—C208—H2102 | 120.459 |
C10—C9—H101 | 119.985 | C209—C208—H2102 | 120.459 |
C9—C10—C11 | 120.50 (13) | C208—C209—C210 | 120.2 (8) |
C9—C10—N2 | 119.73 (9) | C208—C209—H2101 | 119.911 |
C11—C10—N2 | 119.77 (9) | C210—C209—H2101 | 119.911 |
C10—C11—C12 | 119.6 (5) | N202—C210—C209 | 119.7 (1) |
C10—C11—H105 | 120.216 | N202—C210—C211 | 119.8 (1) |
C12—C11—H105 | 120.216 | C209—C210—C211 | 120.49 (14) |
C7—C12—C11 | 119.2 (7) | C210—C211—C212 | 119.7 (8) |
C7—C12—H104 | 120.420 | C210—C211—H2105 | 120.132 |
C11—C12—H104 | 120.419 | C212—C211—H2105 | 120.132 |
C4—N1—N2 | 131.7 (7) | C207—C212—C211 | 118.9 (12) |
C10—N2—N1 | 123.9 (6) | C207—C212—H2104 | 120.545 |
C10—N2—O1 | 113.4 (5) | C211—C212—H2104 | 120.545 |
N1—N2—O1 | 122.5 (8) | C212—H104—H2104 | 150.465 |
O201—N201—N202 | 115 (3) | C211—H105—H2105 | 102.986 |
Experimental details
Crystal data | |
Chemical formula | C12H8I2N2O |
Mr | 450.02 |
Crystal system, space group | Orthorhombic, I2cb |
Temperature (K) | 150 |
a, b, c (Å) | 6.0119 (1), 7.2082 (2), 59.0233 (18) |
V (Å3) | 2557.77 (11) |
Z | 8 |
Radiation type | Mo Kα |
µ (mm−1) | 4.90 |
Crystal size (mm) | 0.20 × 0.19 × 0.01 |
Data collection | |
Diffractometer | Nonius KappaCCD diffractometer |
Absorption correction | Multi-scan (DENZO and SCALEPACK; Otwinowski & Minor, 1996) |
Tmin, Tmax | 0.39, 0.95 |
No. of measured, independent and observed [I > −10.00u(I)] reflections | 2815, 2682, 2681 |
Rint | 0.00 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.055, 0.105, 0.98 |
No. of reflections | 2681 |
No. of parameters | 296 |
No. of restraints | ? |
H-atom treatment | H-atom parameters not refined |
Δρmax, Δρmin (e Å−3) | 1.78, −1.70 |
Absolute structure | Flack & Bernadinelli (1999, 2000), 1226 Friedel-pairs |
Absolute structure parameter | 0.46 (9) |
Computer programs: COLLECT (Nonius BV, 1997–2001), DENZO and SCALEPACK (Otwinowski & Minor, 1996), SIR92 (Altomare et al., 1994), CRYSTALS (Watkin et al., 2001), CAMERON, CRYSTALS.
I1—C1 | 2.095 (6) | I202—C207 | 2.083 (9) |
I2—C7 | 2.098 (6) | O201—N201 | 1.321 (9) |
C1—C2 | 1.397 (7) | N201—N202 | 1.090 (9) |
C1—C6 | 1.390 (8) | N201—C204 | 1.438 (9) |
C2—C3 | 1.407 (8) | N202—C210 | 1.433 (9) |
C3—C4 | 1.405 (7) | C201—C202 | 1.391 (9) |
C4—C5 | 1.377 (7) | C201—C206 | 1.393 (9) |
C4—N1 | 1.417 (6) | C202—C203 | 1.396 (9) |
C5—C6 | 1.376 (7) | C203—C204 | 1.393 (9) |
C7—C8 | 1.391 (8) | C204—C205 | 1.389 (9) |
C7—C12 | 1.394 (8) | C205—C206 | 1.392 (9) |
C8—C9 | 1.380 (8) | C207—C208 | 1.389 (9) |
C9—C10 | 1.372 (7) | C207—C212 | 1.392 (9) |
C10—C11 | 1.406 (7) | C208—C209 | 1.387 (9) |
C10—N2 | 1.459 (7) | C209—C210 | 1.387 (9) |
C11—C12 | 1.400 (7) | C210—C211 | 1.398 (9) |
N2—O1 | 1.322 (7) | C211—C212 | 1.393 (9) |
I201—C201 | 2.088 (9) | ||
I1—C1—C2 | 119.3 (6) | O201—N201—N202 | 115 (3) |
I1—C1—C6 | 118.3 (6) | O201—N201—C204 | 115.1 (17) |
C2—C1—C6 | 122.4 (7) | N202—N201—C204 | 129.8 (18) |
C1—C2—C3 | 118.4 (7) | N201—N202—C210 | 136.8 (19) |
C2—C3—C4 | 119.0 (5) | I201—C201—C202 | 119 (2) |
C3—C4—C5 | 120.49 (13) | I201—C201—C206 | 119 (2) |
C3—C4—N1 | 119.81 (9) | C202—C201—C206 | 121.8 (13) |
C5—C4—N1 | 119.69 (9) | C201—C202—C203 | 118.7 (12) |
C4—C5—C6 | 121.6 (5) | C202—C203—C204 | 120.0 (8) |
C1—C6—C5 | 118.1 (7) | N201—C204—C203 | 119.8 (1) |
I2—C7—C8 | 120.6 (6) | N201—C204—C205 | 119.8 (1) |
I2—C7—C12 | 119.2 (6) | C203—C204—C205 | 120.49 (14) |
C8—C7—C12 | 120.2 (7) | C204—C205—C206 | 120.2 (8) |
C7—C8—C9 | 120.5 (7) | C201—C206—C205 | 118.8 (12) |
C8—C9—C10 | 120.0 (6) | I202—C207—C208 | 119.1 (11) |
C9—C10—C11 | 120.50 (13) | I202—C207—C212 | 119.3 (11) |
C9—C10—N2 | 119.73 (9) | C208—C207—C212 | 121.6 (13) |
C11—C10—N2 | 119.77 (9) | C207—C208—C209 | 119.1 (12) |
C10—C11—C12 | 119.6 (5) | C208—C209—C210 | 120.2 (8) |
C7—C12—C11 | 119.2 (7) | N202—C210—C209 | 119.7 (1) |
C4—N1—N2 | 131.7 (7) | N202—C210—C211 | 119.8 (1) |
C10—N2—N1 | 123.9 (6) | C209—C210—C211 | 120.49 (14) |
C10—N2—O1 | 113.4 (5) | C210—C211—C212 | 119.7 (8) |
N1—N2—O1 | 122.5 (8) | C207—C212—C211 | 118.9 (12) |
The title compound, (I), was obtained in 10% yield as an unexpected product while attempting to convert N,N-dibutyl-4-iodoaniline into its N-oxide with hydrogen peroxide (Demir & Ashaw, 1987), and identified crystallographically. To the best of our knowledge, the direct transformation of a tertiary amine into a diazo compound is unprecedented. Compound (I) has previously been prepared by several routes (e.g. Gabriel, 1876; Wang et al., 1999); the melting point, NMR data and mass spectrum of our product confirmed its identity. A possible mechanism for the formation of this compound is shown in the Scheme below.
Oxidation of (II) by hydrogen peroxide gives the N-oxide (III). This eliminates butene via a Cope reaction (Adams & Kovacic, 1974) before being oxidized again [to give (IV)] and undergoing a second elimination [to give (V)]. Di(hydroxyl)amine (V) then eliminates water to give nitrosamine (VI). From this point, it is likely that the mechanism is similar to that of the reaction between nitrosobenzene and phenylhydroxylamine (Becker & Sternson, 1980) (a radical mechanism is also seen in the presence of base (Russell et al., 1967). Nucleophilic attack by the species that has undergone one elimination (VII) forms dimer (VIII). This undergoes a further elimination (to give IX), followed by displacement of OH− by the lone pair of the adjacent N atom to give (I). (I) crystallizes as an inversion twin [Flack (Flack & Bernardinelli, 1999, 2000) parameter = 0.46 (9)]. The whole molecule is also disordered with an image of itself in the ratio 4:1. The image can be regarded as being due either to a local pseudo-centre of symmery, or a stacking fault with translation of approximately 1/4 along z. This is the preferred description since the structure consists of layers of molecules perpendicular to z, with a layer thickness of z/4. The minimum I···I distances between layers is 4.05 Å. The bond lengths and angles are comparable to similar azoxy compounds. Short intramolecular contacts occur between O1 and H41 (2.04 Å), and between O1 and H101 (2.31 Å), both of these are shorter than the sum of the van der Waals radii (2.68 Å; Rowland & Taylor, 1996).