The title compound, C
9H
19N
3O·C
4H
7NO
2, displays strong intramolecular O—H
N [O
N 2.6743 (13) Å] and N—H
N [N
N 2.6791 (15) Å] hydrogen bonds, and strong intermolecular O—H
N [O
N 2.7949 (15) Å] and N—H
O [N
O 3.0924 (16) Å] hydrogen bonds. This creates chains of perhydropyrimidine molecules, linked by hydrogen bonds. Each chain is linked to a partner chain, through hydrogen bonds to two butane-2,3-dione monooxime molecules, in a structure reminiscent of a ladder.
Supporting information
CCDC reference: 174848
Butane-2,3-dione monoxime (11.73 mmol) was dissolved in ethanol (200 ml) and
2,2-dimethyl-1,3-propanediamine (5.86 mmol) in ethanol (100 ml) was added
dropwise. The solution was refluxed for 2 h and then allowed to cool to room
temperature. Colourless single crystals of (I) were obtained by slow
evaporation.
H atoms bound to N and O were refined isotropically using full matrix
least-squares. H atoms bound to C were allowed to ride on the parent atom
(C—H = 0.96 Å) and their displacement parameters were constrained to
follow the relationship Uiso(H) = 1.2Ueq(C). NB It appears
from the Uiso and bond distance and angle tables that H atoms on C
were in fact refined - please clarify.
Data collection: DIP2000 software (Enraf-Nonius, 1995) and DENZO (Otwinowski & Minor, 1996); cell refinement: DIP2000 software and DENZO; data reduction: DIP2000 software and DENZO; program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: CRYSTALS (Watkin et al., 1996); molecular graphics: ORTEP-3 (Farrugia, 1997); software used to prepare material for publication: CRYSTALS.
2-[1-(Hydroxyimino)ethyl]-2,5,5-trimethylperhydropyrimidine-butane-2,3-dione
monoxime (1/1)
top
Crystal data top
C9H19N3O·C4H7NO2 | Z = 2 |
Mr = 286.38 | F(000) = 312.06 |
Triclinic, P1 | Dx = 1.203 Mg m−3 |
a = 6.4630 (3) Å | Mo Kα radiation, λ = 0.71069 Å |
b = 8.3080 (5) Å | Cell parameters from 9950 reflections |
c = 16.3530 (9) Å | θ = 0–27° |
α = 77.095 (3)° | µ = 0.09 mm−1 |
β = 86.747 (3)° | T = 150 K |
γ = 67.554 (3)° | Block, colourless |
V = 790.65 (8) Å3 | 0.6 × 0.4 × 0.4 mm |
Data collection top
Enraf-Nonius DIP2000 diffractometer | 2703 reflections with I > 3σ(I) |
Graphite monochromator | Rint = 0.02 |
ω scans | θmax = 26.6°, θmin = 0.0° |
Absorption correction: multi-scan (North et al., 1968) | h = 0→8 |
Tmin = 0.950, Tmax = 0.965 | k = −9→10 |
9950 measured reflections | l = −20→20 |
2989 independent reflections | |
Refinement top
Refinement on F | All H-atom parameters refined |
R[F2 > 2σ(F2)] = 0.045 | Chebychev polynomial with 3 parameters (Carruthers & Watkin, 1979),
3.62 1.39 2.47 |
wR(F2) = 0.048 | (Δ/σ)max = 0.006 |
S = 0.94 | Δρmax = 0.24 e Å−3 |
2703 reflections | Δρmin = −0.26 e Å−3 |
263 parameters | |
Crystal data top
C9H19N3O·C4H7NO2 | γ = 67.554 (3)° |
Mr = 286.38 | V = 790.65 (8) Å3 |
Triclinic, P1 | Z = 2 |
a = 6.4630 (3) Å | Mo Kα radiation |
b = 8.3080 (5) Å | µ = 0.09 mm−1 |
c = 16.3530 (9) Å | T = 150 K |
α = 77.095 (3)° | 0.6 × 0.4 × 0.4 mm |
β = 86.747 (3)° | |
Data collection top
Enraf-Nonius DIP2000 diffractometer | 2989 independent reflections |
Absorption correction: multi-scan (North et al., 1968) | 2703 reflections with I > 3σ(I) |
Tmin = 0.950, Tmax = 0.965 | Rint = 0.02 |
9950 measured reflections | |
Refinement top
R[F2 > 2σ(F2)] = 0.045 | 263 parameters |
wR(F2) = 0.048 | All H-atom parameters refined |
S = 0.94 | Δρmax = 0.24 e Å−3 |
2703 reflections | Δρmin = −0.26 e Å−3 |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top | x | y | z | Uiso*/Ueq | |
O1 | 0.65024 (15) | 0.66126 (11) | 0.06487 (5) | 0.0235 | |
O2 | 0.27549 (16) | 0.32646 (12) | 0.41728 (5) | 0.0273 | |
O3 | 0.27105 (17) | 0.51383 (14) | 0.65872 (6) | 0.0342 | |
N1 | 0.54651 (17) | 0.58632 (12) | 0.13235 (6) | 0.0191 | |
N2 | 0.36965 (17) | 0.41213 (13) | 0.25589 (6) | 0.0198 | |
N3 | 0.04684 (18) | 0.50364 (13) | 0.16271 (6) | 0.0205 | |
N4 | 0.26012 (18) | 0.46414 (14) | 0.45491 (6) | 0.0237 | |
C1 | 0.3404 (2) | 0.62220 (14) | 0.11690 (7) | 0.0187 | |
C2 | 0.2177 (2) | 0.73197 (18) | 0.03564 (8) | 0.0284 | |
C3 | 0.2154 (2) | 0.55804 (15) | 0.19176 (7) | 0.0186 | |
C4 | 0.4766 (2) | 0.24186 (15) | 0.22800 (8) | 0.0222 | |
C5 | 0.3030 (2) | 0.17980 (15) | 0.19993 (7) | 0.0227 | |
C6 | 0.1473 (2) | 0.33454 (16) | 0.13426 (7) | 0.0232 | |
C7 | 0.0935 (2) | 0.71419 (17) | 0.23391 (9) | 0.0281 | |
C8 | 0.1680 (2) | 0.12703 (17) | 0.27373 (8) | 0.0263 | |
C9 | 0.4235 (3) | 0.02104 (18) | 0.15906 (9) | 0.0336 | |
C10 | 0.2488 (2) | 0.55543 (18) | 0.58214 (8) | 0.0265 | |
C11 | 0.1928 (2) | 0.74513 (19) | 0.53542 (9) | 0.0325 | |
C12 | 0.2726 (2) | 0.41425 (17) | 0.53552 (7) | 0.0243 | |
C13 | 0.3068 (3) | 0.23039 (19) | 0.58397 (8) | 0.0312 | |
H11 | 0.788 (4) | 0.628 (3) | 0.0895 (13) | 0.051 (4)* | |
H21 | 0.294 (4) | 0.371 (3) | 0.3617 (14) | 0.051 (4)* | |
H31 | −0.047 (3) | 0.499 (2) | 0.2050 (11) | 0.029 (3)* | |
H2 | 0.475 (3) | 0.446 (2) | 0.268 (1) | 0.029 (3)* | |
H111 | 0.232 (3) | 0.754 (3) | 0.4780 (13) | 0.0461 (12)* | |
H112 | 0.279 (3) | 0.800 (2) | 0.5626 (11) | 0.0461 (12)* | |
H113 | 0.034 (4) | 0.803 (3) | 0.5398 (12) | 0.0461 (12)* | |
H131 | 0.363 (3) | 0.215 (3) | 0.6407 (12) | 0.0461 (12)* | |
H132 | 0.408 (4) | 0.140 (3) | 0.5572 (12) | 0.0461 (12)* | |
H133 | 0.163 (4) | 0.215 (3) | 0.5927 (12) | 0.0461 (12)* | |
H81 | 0.051 (3) | 0.092 (3) | 0.2546 (12) | 0.0461 (12)* | |
H82 | 0.085 (3) | 0.226 (3) | 0.3033 (12) | 0.0461 (12)* | |
H83 | 0.267 (3) | 0.030 (3) | 0.3144 (12) | 0.0461 (12)* | |
H41 | 0.570 (3) | 0.151 (2) | 0.275 (1) | 0.031 (2)* | |
H42 | 0.581 (3) | 0.250 (2) | 0.182 (1) | 0.031 (2)* | |
H71 | 0.201 (3) | 0.746 (3) | 0.2588 (12) | 0.0461 (12)* | |
H72 | −0.001 (3) | 0.822 (3) | 0.1932 (12) | 0.0461 (12)* | |
H73 | −0.009 (3) | 0.687 (3) | 0.2765 (12) | 0.0461 (12)* | |
H201 | 0.059 (4) | 0.771 (3) | 0.0434 (12) | 0.0461 (12)* | |
H202 | 0.262 (3) | 0.832 (3) | 0.0156 (12) | 0.0461 (12)* | |
H203 | 0.257 (3) | 0.660 (3) | −0.0066 (12) | 0.0461 (12)* | |
H61 | 0.231 (3) | 0.350 (2) | 0.0825 (11) | 0.031 (2)* | |
H62 | 0.017 (3) | 0.303 (2) | 0.120 (1) | 0.031 (2)* | |
H91 | 0.518 (3) | 0.049 (3) | 0.1112 (12) | 0.0461 (12)* | |
H92 | 0.520 (3) | −0.083 (3) | 0.1986 (12) | 0.0461 (12)* | |
H93 | 0.308 (3) | −0.016 (3) | 0.1384 (12) | 0.0461 (12)* | |
Atomic displacement parameters (Å2) top | U11 | U22 | U33 | U12 | U13 | U23 |
O1 | 0.0213 (4) | 0.0304 (4) | 0.0203 (4) | −0.0141 (4) | 0.0041 (4) | −0.0015 (3) |
O2 | 0.0335 (5) | 0.0379 (5) | 0.0177 (4) | −0.0205 (4) | 0.0028 (4) | −0.0084 (4) |
O3 | 0.0309 (5) | 0.0551 (6) | 0.0238 (4) | −0.0201 (5) | 0.0021 (4) | −0.0162 (4) |
N1 | 0.0207 (5) | 0.0220 (4) | 0.0174 (4) | −0.0114 (4) | 0.0039 (4) | −0.0043 (3) |
N2 | 0.0207 (5) | 0.0256 (5) | 0.0174 (4) | −0.0128 (4) | −0.0007 (4) | −0.0058 (4) |
N3 | 0.0172 (5) | 0.0232 (5) | 0.0234 (5) | −0.0101 (4) | 0.0004 (4) | −0.0052 (4) |
N4 | 0.0192 (5) | 0.0348 (5) | 0.0209 (5) | −0.0133 (4) | 0.0019 (4) | −0.0086 (4) |
C1 | 0.0205 (6) | 0.0189 (5) | 0.0187 (5) | −0.0087 (4) | 0.0014 (5) | −0.0058 (4) |
C2 | 0.0249 (7) | 0.0339 (6) | 0.0249 (6) | −0.0134 (5) | −0.0034 (5) | 0.0014 (5) |
C3 | 0.0182 (5) | 0.0211 (5) | 0.0197 (5) | −0.0099 (4) | 0.0021 (5) | −0.0066 (4) |
C4 | 0.0195 (6) | 0.0227 (5) | 0.0226 (5) | −0.0072 (4) | 0.0007 (5) | −0.0029 (4) |
C5 | 0.0258 (6) | 0.0215 (5) | 0.0235 (5) | −0.0110 (5) | 0.0038 (5) | −0.0074 (4) |
C6 | 0.0265 (6) | 0.0251 (6) | 0.0225 (6) | −0.0132 (5) | −0.0013 (5) | −0.0072 (4) |
C7 | 0.0304 (7) | 0.0269 (6) | 0.0325 (6) | −0.0141 (5) | 0.0118 (6) | −0.0144 (5) |
C8 | 0.0291 (7) | 0.0252 (6) | 0.0276 (6) | −0.0143 (5) | 0.0039 (6) | −0.0051 (5) |
C9 | 0.0400 (8) | 0.0255 (6) | 0.0381 (7) | −0.0130 (6) | 0.0104 (7) | −0.0137 (6) |
C10 | 0.0167 (6) | 0.0419 (7) | 0.0253 (6) | −0.0134 (5) | 0.0026 (5) | −0.0124 (5) |
C11 | 0.0262 (7) | 0.0394 (7) | 0.0363 (7) | −0.0146 (6) | 0.0052 (6) | −0.0141 (6) |
C12 | 0.0174 (6) | 0.0366 (7) | 0.0199 (5) | −0.0109 (5) | 0.0006 (5) | −0.0070 (5) |
C13 | 0.0323 (7) | 0.0368 (7) | 0.0214 (6) | −0.0113 (6) | 0.0016 (6) | −0.0035 (5) |
Geometric parameters (Å, º) top
O1—N1 | 1.4081 (12) | C12—C13 | 1.4938 (19) |
O1—H11 | 0.91 (2) | C5—C8 | 1.5320 (17) |
O2—N4 | 1.3848 (13) | C5—C9 | 1.5306 (17) |
O2—H21 | 0.92 (2) | C13—H131 | 0.980 (19) |
O3—C10 | 1.2237 (16) | C13—H132 | 0.96 (2) |
N1—C1 | 1.2759 (16) | C13—H133 | 0.98 (2) |
N2—C3 | 1.4803 (14) | C8—H81 | 1.00 (2) |
N2—C4 | 1.4808 (15) | C8—H82 | 1.00 (2) |
N2—H2 | 0.879 (18) | C8—H83 | 0.96 (2) |
N3—C3 | 1.4654 (14) | C4—H41 | 0.989 (17) |
N3—C6 | 1.4740 (15) | C4—H42 | 0.995 (18) |
N3—H31 | 0.898 (18) | C7—H71 | 0.97 (2) |
N4—C12 | 1.2879 (16) | C7—H72 | 0.99 (2) |
C1—C2 | 1.5010 (16) | C7—H73 | 0.98 (2) |
C3—C1 | 1.5366 (16) | C2—H201 | 0.96 (2) |
C5—C4 | 1.5301 (16) | C2—H202 | 0.97 (2) |
C5—C6 | 1.5286 (16) | C2—H203 | 0.975 (19) |
C3—C7 | 1.5284 (16) | C6—H61 | 0.990 (17) |
C10—C11 | 1.5023 (19) | C6—H62 | 1.024 (17) |
C10—C12 | 1.4930 (17) | C9—H91 | 1.01 (2) |
C11—H111 | 0.95 (2) | C9—H92 | 0.97 (2) |
C11—H112 | 1.016 (19) | C9—H93 | 1.01 (2) |
C11—H113 | 0.96 (2) | | |
| | | |
N1—O1—H11 | 99.1 (13) | C12—C13—H132 | 112.3 (11) |
N4—O2—H21 | 102.7 (12) | H131—C13—H132 | 110.5 (16) |
O1—N1—C1 | 113.06 (9) | C12—C13—H133 | 110.8 (11) |
C3—N2—C4 | 113.52 (8) | H131—C13—H133 | 104.3 (16) |
C3—N2—H2 | 108.2 (10) | H132—C13—H133 | 109.8 (16) |
C4—N2—H2 | 108.4 (11) | C5—C8—H81 | 111.2 (11) |
C3—N3—C6 | 112.5 (1) | C5—C8—H82 | 113.9 (11) |
C3—N3—H31 | 106.8 (10) | H81—C8—H82 | 105.0 (16) |
C6—N3—H31 | 112.9 (10) | C5—C8—H83 | 109.4 (12) |
O2—N4—C12 | 111.6 (1) | H81—C8—H83 | 109.8 (16) |
N1—C1—C3 | 114.66 (9) | H82—C8—H83 | 107.3 (15) |
N1—C1—C2 | 124.41 (11) | N2—C4—H41 | 108.1 (9) |
C3—C1—C2 | 120.7 (1) | C5—C4—H41 | 109.7 (9) |
N2—C3—C7 | 107.16 (9) | N2—C4—H42 | 112.2 (9) |
N2—C3—C1 | 112.22 (9) | C5—C4—H42 | 108.8 (9) |
N2—C4—C5 | 111.8 (1) | H41—C4—H42 | 106.0 (13) |
N3—C3—N2 | 110.88 (9) | C3—C7—H71 | 110.1 (12) |
N3—C3—C1 | 110.26 (9) | C3—C7—H72 | 111.9 (11) |
N3—C3—C7 | 107.9 (1) | H71—C7—H72 | 107.0 (16) |
N3—C6—C5 | 113.85 (9) | C3—C7—H73 | 111.9 (11) |
N4—C12—C10 | 115.69 (11) | H71—C7—H73 | 110.3 (16) |
N4—C12—C13 | 125.26 (12) | H72—C7—H73 | 105.4 (16) |
C1—C3—C7 | 108.25 (9) | C1—C2—H201 | 109.8 (11) |
O3—C10—C11 | 121.16 (12) | C1—C2—H202 | 109.9 (11) |
O3—C10—C12 | 118.67 (12) | H201—C2—H202 | 111.1 (16) |
C11—C10—C12 | 120.15 (11) | C1—C2—H203 | 109.4 (11) |
C10—C11—H111 | 112.7 (11) | H201—C2—H203 | 109.0 (16) |
C10—C11—H112 | 109.0 (11) | H202—C2—H203 | 107.6 (16) |
H111—C11—H112 | 107.6 (15) | N3—C6—H61 | 110.4 (9) |
C10—C11—H113 | 105.4 (11) | C5—C6—H61 | 108.8 (10) |
H111—C11—H113 | 110.4 (17) | N3—C6—H62 | 106.5 (9) |
H112—C11—H113 | 111.9 (15) | C5—C6—H62 | 108.9 (9) |
C10—C12—C13 | 119.05 (11) | H61—C6—H62 | 108.3 (13) |
C8—C5—C4 | 111.6 (1) | C5—C9—H91 | 112.7 (11) |
C8—C5—C6 | 110.1 (1) | C5—C9—H92 | 112.6 (11) |
C4—C5—C6 | 107.24 (9) | H91—C9—H92 | 107.3 (16) |
C8—C5—C9 | 110.0 (1) | C5—C9—H93 | 108.8 (11) |
C4—C5—C9 | 108.92 (11) | H91—C9—H93 | 109.6 (15) |
C6—C5—C9 | 108.9 (1) | H92—C9—H93 | 105.6 (15) |
C12—C13—H131 | 108.8 (11) | | |
| | | |
O1—N1—C1—C2 | 0.22 (16) | C2—C1—C3—N3 | 39.37 (14) |
O1—N1—C1—C3 | −174.46 (9) | C2—C1—C3—C7 | −78.42 (14) |
C4—N2—C3—N3 | 54.24 (13) | N2—C4—C5—C6 | 53.34 (13) |
C4—N2—C3—C1 | −69.57 (13) | N2—C4—C5—C8 | −67.33 (13) |
C4—N2—C3—C7 | 171.73 (11) | N2—C4—C5—C9 | 171.02 (10) |
C3—N2—C4—C5 | −56.05 (14) | C4—C5—C6—N3 | −53.79 (14) |
C6—N3—C3—N2 | −52.95 (12) | C8—C5—C6—N3 | 67.81 (14) |
C6—N3—C3—C1 | 71.98 (12) | C9—C5—C6—N3 | −171.49 (12) |
C6—N3—C3—C7 | −170.00 (10) | O2—N4—C12—C10 | −177.73 (11) |
C3—N3—C6—C5 | 55.30 (14) | O2—N4—C12—C13 | 1.9 (2) |
N1—C1—C3—N2 | −21.58 (14) | O3—C10—C12—N4 | −176.18 (14) |
N1—C1—C3—N3 | −145.73 (10) | O3—C10—C12—C13 | 4.2 (2) |
N1—C1—C3—C7 | 96.47 (12) | C11—C10—C12—N4 | 5.37 (19) |
C2—C1—C3—N2 | 163.52 (11) | C11—C10—C12—C13 | −174.25 (14) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2···N1 | 0.88 (2) | 2.37 (2) | 2.6791 (15) | 101 (1) |
N2—H2···O3i | 0.88 (2) | 2.25 (2) | 3.0924 (16) | 161 (1) |
O1—H11···N3ii | 0.91 (3) | 1.91 (2) | 2.7949 (15) | 162 (2) |
O2—H21···N2 | 0.92 (2) | 1.77 (2) | 2.6743 (13) | 168 (2) |
C6—H61···O1iii | 0.99 (2) | 2.50 (2) | 3.4377 (14) | 159 (2) |
C11—H111···N4 | 0.95 (2) | 2.46 (2) | 2.8115 (18) | 102 (2) |
C13—H131···O3 | 0.98 (2) | 2.40 (2) | 2.8162 (19) | 105 (2) |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x+1, y, z; (iii) −x+1, −y+1, −z. |
Experimental details
Crystal data |
Chemical formula | C9H19N3O·C4H7NO2 |
Mr | 286.38 |
Crystal system, space group | Triclinic, P1 |
Temperature (K) | 150 |
a, b, c (Å) | 6.4630 (3), 8.3080 (5), 16.3530 (9) |
α, β, γ (°) | 77.095 (3), 86.747 (3), 67.554 (3) |
V (Å3) | 790.65 (8) |
Z | 2 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.6 × 0.4 × 0.4 |
|
Data collection |
Diffractometer | Enraf-Nonius DIP2000 diffractometer |
Absorption correction | Multi-scan (North et al., 1968) |
Tmin, Tmax | 0.950, 0.965 |
No. of measured, independent and observed [I > 3σ(I)] reflections | 9950, 2989, 2703 |
Rint | 0.02 |
(sin θ/λ)max (Å−1) | 0.629 |
|
Refinement |
R[F2 > 2σ(F2)], wR(F2), S | 0.045, 0.048, 0.94 |
No. of reflections | 2703 |
No. of parameters | 263 |
No. of restraints | ? |
H-atom treatment | All H-atom parameters refined |
Δρmax, Δρmin (e Å−3) | 0.24, −0.26 |
Selected geometric parameters (Å, º) topO1—N1 | 1.4081 (12) | N3—C6 | 1.4740 (15) |
O2—N4 | 1.3848 (13) | N4—C12 | 1.2879 (16) |
O3—C10 | 1.2237 (16) | C1—C2 | 1.5010 (16) |
N1—C1 | 1.2759 (16) | C3—C1 | 1.5366 (16) |
N2—C3 | 1.4803 (14) | C5—C4 | 1.5301 (16) |
N2—C4 | 1.4808 (15) | C5—C6 | 1.5286 (16) |
N3—C3 | 1.4654 (14) | C10—C12 | 1.4930 (17) |
| | | |
O1—N1—C1 | 113.06 (9) | N2—C4—C5 | 111.8 (1) |
C3—N2—C4 | 113.52 (8) | N3—C3—N2 | 110.88 (9) |
C3—N3—C6 | 112.5 (1) | N3—C3—C1 | 110.26 (9) |
O2—N4—C12 | 111.6 (1) | N3—C3—C7 | 107.9 (1) |
N1—C1—C3 | 114.66 (9) | N3—C6—C5 | 113.85 (9) |
N1—C1—C2 | 124.41 (11) | N4—C12—C10 | 115.69 (11) |
N2—C3—C7 | 107.16 (9) | O3—C10—C11 | 121.16 (12) |
N2—C3—C1 | 112.22 (9) | O3—C10—C12 | 118.67 (12) |
| | | |
C4—N2—C3—C1 | −69.57 (13) | C8—C5—C6—N3 | 67.81 (14) |
C3—N2—C4—C5 | −56.05 (14) | O2—N4—C12—C10 | −177.73 (11) |
C6—N3—C3—C1 | 71.98 (12) | O3—C10—C12—N4 | −176.18 (14) |
C3—N3—C6—C5 | 55.30 (14) | C11—C10—C12—C13 | −174.25 (14) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N2—H2···N1 | 0.88 (2) | 2.37 (2) | 2.6791 (15) | 101 (1) |
N2—H2···O3i | 0.88 (2) | 2.25 (2) | 3.0924 (16) | 161 (1) |
O1—H11···N3ii | 0.91 (3) | 1.91 (2) | 2.7949 (15) | 162 (2) |
O2—H21···N2 | 0.92 (2) | 1.77 (2) | 2.6743 (13) | 168 (2) |
C6—H61···O1iii | 0.99 (2) | 2.50 (2) | 3.4377 (14) | 159 (2) |
C11—H111···N4 | 0.95 (2) | 2.46 (2) | 2.8115 (18) | 102 (2) |
C13—H131···O3 | 0.98 (2) | 2.40 (2) | 2.8162 (19) | 105 (2) |
Symmetry codes: (i) −x+1, −y+1, −z+1; (ii) x+1, y, z; (iii) −x+1, −y+1, −z. |
Some recently reviewed data shows that oximes, although being classical ligands (Chakravorty, 1974; Keeney et al., 1984), display a variety of reactivity modes unusual even in the context of modern coordination chemistry (Kukushkin et al., 1996, 1999; Costes et al., 1997). As far as the redox conversions of oxime species are concerned, they can be either reduced or oxidized in metal-mediated reactions. We report here the structure of the molecular complex of 2-[1-(hydroxyimino)ethyl]-2,5,5-trimethylperhydropyrimidine and butane-2,3-dione monoxime, (I). \sch
The structure of (I) has an asymmetric unit containing one 2-[1-(hydroxyimino)ethyl]-2,5,5-trimethylperhydropyrimidine fragment and one butane-2,3-dione monoxime fragment, as shown in Fig. 1. The torsion angles O2—N4—C12—C10 [-177.73 (11)°], O3—C10—C12—N4 [-174.18 (14)°] and C11—C10—C12—C13 [-174.25 (14)°] indicate that the butane-2,3-dione monoxime molecule is nearly planar. The conformation of the perhydropyrimidine molecule is defined by the torsion angles C3—N2—C4—C5 [-56.05 (14)°], C3—N3—C6—C5 [55.30 (14)°], C4—N2—C3—C1 [-69.57 (13)°] and C8—C5—C6—N3 [67.81 (14)°]. The perhydropyrimidine moiety adopts an aminal structure, with the six-membered ring in a chair conformation and the oxime fragment, C(CH3)NOH, appearing as an axial substituent.
The perhydropyrimidine molecules form hydrogen-bonded chains which run parallel to [100]. These chains are cross-linked along the [001] direction via hydrogen bonds involving the butane-2,3-dione monoxime moieties, forming a pattern reminiscent of a ladder (Fig. 2).
A major point of interest is the presence of a hydrogen contact between the equatorial H atom on the ring atom N2 with atom N1 of the axial oxime group (Fig. 1). This bond is rather weak, with an H···N1 (acceptor) separation of 2.37 (2) Å. However, this hydrogen bond locks the ring in a chair conformation, in which the side-chain containing the oxime is axial and inhibits the rotation of the oxime substituent around the C1—C3 bond which, due to its length of 1.5366 (16) Å, must be considered as a single bond.
Another hydrogen bond is formed between atom O2 of the butane-2,3-dione monoxime molecule and the ring atom N2. This bond, with an H···N2 (acceptor) separation of 1.77 (2) Å, is stronger than the intramolecular bond considered above (Ishida & Kashino 1999; Lavender et al., 1999).
Intermolecular hydrogen bonding occurs between the ring atom N2 and atom O3i of a symmetry-related butane-2,3-dione monoxime molecule [symmetry code: (i) 1 - x, 1 - y, 1 - z]. This bond is weak, with an H···N1 (acceptor) separation of 2.25 (2) Å. It should be noted that considering these hydrogen bonds N2—H···N1, N2—H···O3i and O2—H···N2, would lead erroneously to the conclusion that N2 and N3 have distinctly different environments, when, in fact, these atoms are equivalent. This is reflected in the lengthening of the N2—C3 bond [1.4803 (14) Å] with respect to the N3—C3 bond [1.4654 (14) Å].
C—H···N and C—H···O hydrogen bonds are also formed (Table 2). In the present study, the intramolecular and intermolecular hydrogen-bond lengths are comparable with the values found in related complexes (Steiner, 2000, 2001; Elerman et al., 1998). The bond lengths and angles within the ring and oxime fragments compare well with those reported for a six-membered aminal (Fenton et al., 1985; Raston et al., 1978).