Gradual evolution of hydro­gen-bonding patterns with the carbamoyl­cyano­nitro­somethanide anion in a series of aliphatic di­ammonium salts

Developing the structures of organic materials that rely on the hydro­gen bonding of multifunctional substrates is often complicated due to a competition between various possible motifs. In this context, the illustrative case of the carbamoyl­cyano­nitro­somethanide anion, [ONC(CN)–C(O)NH₂]⁻, suggests sufficient control over the crystal lattice with a set of supra­molecular synthons, which are specific to all the present nitroso, carbamoyl and cyano groups. The structures of the carbamoyl­cyano­nitro­somethanide salts of ethane-1,2-di­am­monium, C₂H₁₀N₂²⁺·2C₃H₂N₃O₂⁻, (1), piperazine-1,4-diium, C₄H₁₂N₂²⁺·2C₃H₂N₃O₂⁻, (2), butane-1,4-di­ammonium, C₄H₁₄N₂²⁺·2C₃H₂N₃O₂⁻, (3), and hexane-1,6-di­ammonium, C₆H₁₈N₂²⁺·2C₃H₂N₃O₂⁻, (4), reveal two- and three-dimensional hydro­gen-bonded frameworks governed by a set of site-selective inter­actions. The strongest N—H...O hydro­gen bonds [N...O = 2.6842 (17)–2.8718 (17) Å, mean 2.776 (2) Å] are associated with the polarized ammonium N—H donors and nitroso O-atom acceptors, which sustain invariant motifs in the form of nitroso/ammonium dimers. Subtle structural changes within this series of compounds concern the rupture of some weaker inter­actions, i.e. mutual hydrogen bonds of the carbamoyl groups in (1)–(3) [N...O = 2.910 (2)–2.9909 (18) Å; mean 2.950 (2) Å] and carbamo­yl/nitrile hydrogen bonds in (1), (2) and (4) [N...N = 2.936 (2)–3.003 (3) Å, mean 2.977 (2) Å], providing a gradual evolution of the hydro­gen-bonding pattern. A hierarchy of the synthons involving three different groups could be applicable to supra­molecular synthesis with polyfunctional methanide species, suggesting also a degree of control over layered and inter­penetrated hydro­gen-bonded networks.

Computing details

For all structures, data collection: SMART-NT (Bruker, 1998); cell refinement: SAINT-NT (Bruker, 1999); data reduction: SAINT-NT (Bruker, 1999); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: DIAMOND (Brandenburg, 1999); software used to prepare material for publication: WinGX (Farrugia, 2012).

Ethane-1,2-bis(aminium) bis(nitrosocarbamoylcyanomethanide) (1)

Crystal data

C2H10N2^2+·2C3H2N3O2^−	Z = 1
Mr = 286.27	F(000) = 150
Triclinic, P1	Dx = 1.483 Mg m^−3
a = 7.1203 (8) Å	Mo Kα radiation, λ = 0.71073 Å
b = 7.2221 (10) Å	Cell parameters from 2089 reflections
c = 7.3808 (9) Å	θ = 3.0–29.0°
α = 96.813 (8)°	µ = 0.12 mm^−1
β = 106.031 (7)°	T = 173 K
γ = 114.329 (8)°	Prism, orange
V = 320.47 (7) Å^3	0.26 × 0.24 × 0.19 mm

Data collection

Bruker APEXII CCD diffractometer	1318 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.026
Graphite monochromator	θmax = 29.0°, θmin = 3.0°
φ and ω scans	h = −9→9
2089 measured reflections	k = −9→9
1697 independent reflections	l = −10→5

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.044	Hydrogen site location: difference Fourier map
wR(F^2) = 0.136	All H-atom parameters refined
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0756P)^2 + 0.0936P] where P = (Fo^2 + 2Fc^2)/3
1697 reflections	(Δ/σ)max < 0.001
119 parameters	Δρmax = 0.58 e Å^−3
0 restraints	Δρmin = −0.19 e Å^−3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.1110 (2)	0.51496 (18)	0.23969 (16)	0.0448 (3)
O2	0.47120 (18)	0.73718 (16)	0.90503 (15)	0.0395 (3)
N1	0.1997 (2)	0.4770 (2)	0.40196 (18)	0.0368 (3)
N2	0.2682 (4)	0.9747 (3)	0.5574 (3)	0.0702 (6)
N3	0.3719 (3)	0.4045 (2)	0.7449 (2)	0.0415 (3)
N4	0.1503 (2)	0.8405 (2)	0.05417 (19)	0.0350 (3)
C1	0.2849 (2)	0.6277 (2)	0.56269 (19)	0.0312 (3)
C2	0.2787 (3)	0.8230 (2)	0.5641 (2)	0.0406 (4)
C3	0.3837 (2)	0.5932 (2)	0.7510 (2)	0.0299 (3)
C4	0.0343 (3)	0.9628 (2)	0.0889 (2)	0.0346 (3)
H1	0.434 (3)	0.370 (3)	0.862 (3)	0.044 (5)*
H2	0.305 (4)	0.314 (4)	0.635 (3)	0.052 (6)*
H3	0.173 (4)	0.777 (4)	0.156 (4)	0.059 (6)*
H4	0.075 (4)	0.744 (4)	−0.039 (4)	0.057 (6)*
H5	0.280 (4)	0.929 (3)	0.045 (3)	0.047 (5)*
H4A	−0.095 (3)	0.871 (3)	0.117 (3)	0.045 (5)*
H4B	0.152 (4)	1.082 (4)	0.202 (3)	0.056 (6)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0588 (7)	0.0387 (6)	0.0305 (5)	0.0240 (5)	0.0053 (5)	0.0077 (4)
O2	0.0451 (6)	0.0322 (5)	0.0293 (5)	0.0151 (4)	0.0026 (4)	0.0038 (4)
N1	0.0429 (7)	0.0353 (6)	0.0301 (6)	0.0186 (5)	0.0098 (5)	0.0076 (5)
N2	0.1054 (16)	0.0465 (9)	0.0604 (11)	0.0464 (10)	0.0154 (10)	0.0129 (8)
N3	0.0552 (8)	0.0338 (7)	0.0358 (7)	0.0237 (6)	0.0117 (6)	0.0105 (5)
N4	0.0406 (7)	0.0323 (6)	0.0283 (6)	0.0180 (5)	0.0065 (5)	0.0055 (5)
C1	0.0333 (7)	0.0285 (6)	0.0279 (7)	0.0132 (5)	0.0079 (5)	0.0065 (5)
C2	0.0519 (9)	0.0353 (7)	0.0302 (7)	0.0221 (7)	0.0065 (6)	0.0061 (5)
C3	0.0283 (6)	0.0291 (6)	0.0298 (6)	0.0120 (5)	0.0091 (5)	0.0080 (5)
C4	0.0431 (8)	0.0362 (7)	0.0282 (7)	0.0212 (6)	0.0131 (6)	0.0109 (5)

Geometric parameters (Å, º)

O1—N1	1.3081 (17)	N4—H3	0.93 (2)
O2—C3	1.2479 (17)	N4—H4	0.79 (3)
N1—C1	1.3084 (18)	N4—H5	0.91 (2)
N2—C2	1.134 (2)	C1—C2	1.428 (2)
N3—C3	1.3250 (19)	C1—C3	1.4747 (19)
N3—H1	0.96 (2)	C4—C4^i	1.510 (3)
N3—H2	0.85 (2)	C4—H4A	0.98 (2)
N4—C4	1.4806 (19)	C4—H4B	0.99 (2)
O1—N1—C1	116.64 (12)	C2—C1—C3	118.33 (12)
C3—N3—H1	121.3 (12)	N2—C2—C1	177.23 (18)
C3—N3—H2	117.4 (15)	O2—C3—N3	123.44 (13)
H1—N3—H2	121 (2)	O2—C3—C1	120.14 (12)
C4—N4—H3	109.6 (15)	N3—C3—C1	116.42 (13)
C4—N4—H4	110.6 (18)	N4—C4—C4^i	109.82 (15)
H3—N4—H4	104 (2)	N4—C4—H4A	107.7 (12)
C4—N4—H5	108.6 (13)	C4^i—C4—H4A	111.1 (12)
H3—N4—H5	112 (2)	N4—C4—H4B	101.4 (13)
H4—N4—H5	113 (2)	C4^i—C4—H4B	111.7 (13)
N1—C1—C2	122.37 (13)	H4A—C4—H4B	114.5 (18)
N1—C1—C3	119.26 (13)
O1—N1—C1—C2	1.3 (2)	C2—C1—C3—O2	−4.3 (2)
O1—N1—C1—C3	178.86 (12)	N1—C1—C3—N3	−2.4 (2)
N1—C1—C3—O2	177.99 (14)	C2—C1—C3—N3	175.29 (15)

Symmetry code: (i) −x, −y+2, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N4—H3···O1	0.93 (2)	1.98 (2)	2.8134 (18)	148 (2)
N4—H4···O1^ii	0.79 (3)	1.91 (3)	2.6966 (18)	172 (2)
N4—H5···O2^iii	0.91 (2)	2.24 (2)	3.0358 (19)	146.8 (18)
N4—H5···O2^iv	0.91 (2)	2.61 (2)	3.0964 (18)	114.2 (16)
N3—H1···O2^v	0.96 (2)	2.03 (2)	2.9909 (18)	172.8 (18)
N3—H2···N2^vi	0.85 (2)	2.34 (2)	2.936 (2)	128.2 (19)
C4—H4A···O2^vii	0.98 (2)	2.73 (2)	3.415 (2)	127.2 (15)
C4—H4A···N3^viii	0.98 (2)	2.69 (2)	3.649 (2)	165.3 (16)

Symmetry codes: (ii) −x, −y+1, −z; (iii) −x+1, −y+2, −z+1; (iv) x, y, z−1; (v) −x+1, −y+1, −z+2; (vi) x, y−1, z; (vii) x−1, y, z−1; (viii) −x, −y+1, −z+1.

Piperazine-1,4-diium bis(nitrosocarbamoylcyanomethanide) (2)

Crystal data

C4H12N2^2+·2C3H2N3O2^−	F(000) = 656
Mr = 312.31	Dx = 1.467 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 14.5686 (7) Å	Cell parameters from 13353 reflections
b = 7.1704 (4) Å	θ = 3.0–28.3°
c = 13.9658 (6) Å	µ = 0.12 mm^−1
β = 104.209 (3)°	T = 173 K
V = 1414.27 (12) Å^3	Prism, orange
Z = 4	0.35 × 0.32 × 0.10 mm

Data collection

Bruker APEXII CCD diffractometer	1311 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.054
Graphite monochromator	θmax = 28.3°, θmin = 3.0°
φ and ω scans	h = −19→19
13353 measured reflections	k = −9→9
1760 independent reflections	l = −18→18

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.050	Hydrogen site location: difference Fourier map
wR(F^2) = 0.133	All H-atom parameters refined
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0777P)^2 + 0.1651P] where P = (Fo^2 + 2Fc^2)/3
1760 reflections	(Δ/σ)max < 0.001
132 parameters	Δρmax = 0.37 e Å^−3
0 restraints	Δρmin = −0.24 e Å^−3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.11405 (8)	0.53298 (16)	0.24632 (8)	0.0281 (3)
O2	0.43535 (8)	0.46166 (16)	0.34798 (8)	0.0272 (3)
N1	0.19508 (9)	0.51702 (17)	0.22185 (9)	0.0236 (3)
N2	0.25522 (11)	0.4914 (2)	0.47511 (10)	0.0419 (5)
N3	0.37210 (11)	0.4857 (2)	0.18332 (10)	0.0287 (4)
N4	0.03233 (10)	0.54442 (19)	0.41360 (9)	0.0227 (3)
C1	0.27036 (11)	0.49663 (19)	0.29527 (11)	0.0209 (4)
C2	0.26370 (11)	0.4928 (2)	0.39552 (12)	0.0265 (4)
C3	0.36579 (11)	0.4794 (2)	0.27681 (11)	0.0214 (4)
C4	0.04769 (11)	0.6751 (2)	0.49884 (11)	0.0237 (4)
C5	0.02980 (11)	0.3488 (2)	0.44759 (12)	0.0256 (4)
H1	0.4296 (15)	0.478 (2)	0.1731 (14)	0.028 (5)*
H2	0.3215 (14)	0.502 (2)	0.1392 (13)	0.025 (5)*
H3	0.0794 (13)	0.554 (2)	0.3812 (13)	0.028 (5)*
H4	−0.0239 (14)	0.565 (2)	0.3662 (14)	0.030 (5)*
H4A	0.0498 (12)	0.798 (2)	0.4761 (12)	0.025 (4)*
H4B	0.1081 (11)	0.646 (2)	0.5396 (11)	0.022 (4)*
H5A	0.0170 (13)	0.269 (3)	0.3890 (14)	0.039 (5)*
H5B	0.0907 (12)	0.319 (2)	0.4907 (12)	0.027 (4)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0185 (6)	0.0430 (7)	0.0222 (6)	0.0025 (5)	0.0038 (4)	0.0012 (5)
O2	0.0184 (6)	0.0428 (7)	0.0184 (6)	0.0003 (4)	0.0007 (4)	0.0005 (4)
N1	0.0190 (7)	0.0284 (7)	0.0229 (7)	−0.0010 (5)	0.0042 (5)	−0.0004 (5)
N2	0.0240 (8)	0.0792 (13)	0.0217 (8)	−0.0012 (7)	0.0039 (6)	−0.0016 (7)
N3	0.0194 (8)	0.0489 (10)	0.0173 (7)	0.0004 (6)	0.0039 (6)	0.0039 (6)
N4	0.0160 (7)	0.0349 (8)	0.0167 (7)	−0.0010 (5)	0.0028 (5)	0.0013 (5)
C1	0.0180 (8)	0.0247 (8)	0.0192 (8)	−0.0017 (6)	0.0030 (6)	−0.0004 (6)
C2	0.0144 (8)	0.0392 (10)	0.0242 (9)	−0.0007 (6)	0.0018 (6)	−0.0006 (6)
C3	0.0194 (8)	0.0231 (8)	0.0203 (8)	−0.0023 (6)	0.0023 (6)	−0.0007 (6)
C4	0.0223 (8)	0.0231 (9)	0.0230 (8)	−0.0026 (6)	0.0007 (6)	0.0010 (6)
C5	0.0227 (8)	0.0274 (9)	0.0257 (8)	0.0023 (6)	0.0039 (6)	−0.0043 (7)

Geometric parameters (Å, º)

O1—N1	1.3120 (16)	N4—H4	0.93 (2)
O2—C3	1.2396 (19)	C1—C2	1.427 (2)
N1—C1	1.3129 (19)	C1—C3	1.480 (2)
N2—C2	1.148 (2)	C4—C5^i	1.509 (2)
N3—C3	1.332 (2)	C4—H4A	0.937 (17)
N3—H1	0.89 (2)	C4—H4B	0.947 (16)
N3—H2	0.84 (2)	C5—C4^i	1.509 (2)
N4—C5	1.484 (2)	C5—H5A	0.978 (19)
N4—C4	1.488 (2)	C5—H5B	0.966 (17)
N4—H3	0.91 (2)
O1—N1—C1	116.02 (12)	O2—C3—C1	119.13 (14)
C3—N3—H1	116.9 (12)	N3—C3—C1	117.49 (14)
C3—N3—H2	117.6 (12)	N4—C4—C5^i	109.94 (12)
H1—N3—H2	125.5 (17)	N4—C4—H4A	109.3 (10)
C5—N4—C4	110.49 (12)	C5^i—C4—H4A	111.4 (10)
C5—N4—H3	108.3 (10)	N4—C4—H4B	105.9 (9)
C4—N4—H3	111.3 (11)	C5^i—C4—H4B	112.0 (9)
C5—N4—H4	106.8 (11)	H4A—C4—H4B	108.0 (14)
C4—N4—H4	113.8 (11)	N4—C5—C4^i	110.27 (13)
H3—N4—H4	105.8 (15)	N4—C5—H5A	107.5 (10)
N1—C1—C2	121.57 (14)	C4^i—C5—H5A	109.6 (10)
N1—C1—C3	120.90 (14)	N4—C5—H5B	108.5 (10)
C2—C1—C3	117.53 (13)	C4^i—C5—H5B	110.5 (9)
N2—C2—C1	177.70 (17)	H5A—C5—H5B	110.5 (14)
O2—C3—N3	123.37 (15)
O1—N1—C1—C2	−0.2 (2)	N1—C1—C3—N3	0.1 (2)
O1—N1—C1—C3	−179.32 (12)	C2—C1—C3—N3	−179.04 (14)
N1—C1—C3—O2	179.48 (13)	C5—N4—C4—C5^i	−58.06 (17)
C2—C1—C3—O2	0.3 (2)	C4—N4—C5—C4^i	58.26 (17)

Symmetry code: (i) −x, −y+1, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N4—H3···O1	0.91 (2)	2.072 (19)	2.8719 (17)	145.7 (16)
N4—H4···O1^ii	0.93 (2)	1.80 (2)	2.6842 (17)	158.3 (16)
N3—H1···O2^iii	0.89 (2)	2.06 (2)	2.9483 (19)	178.8 (18)
N3—H2···N2^iv	0.84 (2)	2.258 (18)	2.992 (2)	145.4 (16)
C4—H4A···O2^v	0.937 (17)	2.429 (17)	3.1056 (19)	129.0 (13)
C5—H5A···O2^vi	0.978 (19)	2.503 (18)	3.255 (2)	133.6 (13)

Symmetry codes: (ii) −x, y, −z+1/2; (iii) −x+1, y, −z+1/2; (iv) x, −y+1, z−1/2; (v) x−1/2, y+1/2, z; (vi) x−1/2, y−1/2, z.

Butane-1,4-bis(aminium) bis(nitrosocarbamoylcyanomethanide) (3)

Crystal data

C4H14N2^2+·2C3H2N3O2^−	F(000) = 664
Mr = 314.32	Dx = 1.412 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71073 Å
a = 16.4095 (5) Å	Cell parameters from 14141 reflections
b = 6.7848 (3) Å	θ = 2.8–28.2°
c = 14.8471 (5) Å	µ = 0.11 mm^−1
β = 116.556 (3)°	T = 173 K
V = 1478.61 (10) Å^3	Prism, yellow
Z = 4	0.46 × 0.37 × 0.22 mm

Data collection

Bruker APEXII CCD diffractometer	1463 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.040
Graphite monochromator	θmax = 28.2°, θmin = 2.8°
φ and ω scans	h = −21→21
14141 measured reflections	k = −8→8
1816 independent reflections	l = −19→19

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.059	Hydrogen site location: difference Fourier map
wR(F^2) = 0.166	All H-atom parameters refined
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0832P)^2 + 2.1745P] where P = (Fo^2 + 2Fc^2)/3
1816 reflections	(Δ/σ)max < 0.001
136 parameters	Δρmax = 0.71 e Å^−3
7 restraints	Δρmin = −0.32 e Å^−3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.24644 (10)	0.2413 (2)	0.12285 (10)	0.0336 (4)
O2	0.15729 (10)	0.2978 (2)	0.37397 (11)	0.0331 (4)
N1	0.26504 (11)	0.2326 (2)	0.21751 (12)	0.0267 (4)
N2	0.03694 (12)	0.3635 (3)	0.10843 (14)	0.0369 (5)
N3	0.30566 (12)	0.2324 (3)	0.41567 (14)	0.0327 (4)
C1	0.19907 (12)	0.2707 (3)	0.24185 (14)	0.0233 (4)
C2	0.10856 (13)	0.3224 (3)	0.16912 (14)	0.0258 (4)
C3	0.21926 (13)	0.2679 (3)	0.34960 (15)	0.0260 (4)
N4	0.38707 (11)	0.1879 (3)	0.07040 (13)	0.0279 (4)
C4	0.44979 (15)	0.3611 (4)	0.10384 (16)	0.0365 (5)
C5	0.52132 (15)	0.3459 (4)	0.21378 (17)	0.0387 (5)
H1	0.3189 (18)	0.231 (4)	0.4773 (18)	0.039 (7)*
H2	0.3399 (18)	0.210 (4)	0.390 (2)	0.042 (7)*
H3	0.344 (2)	0.188 (4)	0.097 (2)	0.044 (7)*
H4	0.3537 (16)	0.188 (4)	0.004 (2)	0.030 (6)*
H5	0.4172 (19)	0.065 (5)	0.087 (2)	0.047 (7)*
H4A	0.4095 (17)	0.485 (3)	0.089 (2)	0.047 (7)*
H4B	0.4828 (17)	0.362 (4)	0.0571 (18)	0.048 (7)*
H5A	0.5592 (18)	0.214 (3)	0.227 (2)	0.047 (8)*
H5B	0.569 (2)	0.463 (4)	0.236 (3)	0.080 (11)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0302 (8)	0.0512 (10)	0.0242 (7)	0.0071 (6)	0.0165 (6)	0.0040 (6)
O2	0.0308 (7)	0.0456 (9)	0.0290 (7)	0.0050 (6)	0.0190 (6)	0.0014 (6)
N1	0.0266 (8)	0.0301 (9)	0.0259 (8)	0.0013 (6)	0.0140 (7)	0.0017 (6)
N2	0.0313 (9)	0.0485 (12)	0.0342 (9)	0.0062 (8)	0.0177 (8)	0.0068 (8)
N3	0.0291 (9)	0.0466 (11)	0.0252 (8)	0.0054 (8)	0.0146 (7)	0.0011 (8)
C1	0.0244 (9)	0.0239 (9)	0.0246 (9)	0.0015 (7)	0.0137 (7)	0.0007 (7)
C2	0.0294 (9)	0.0277 (10)	0.0276 (9)	0.0018 (7)	0.0193 (8)	0.0021 (7)
C3	0.0293 (9)	0.0253 (10)	0.0277 (9)	0.0002 (7)	0.0166 (8)	0.0001 (7)
N4	0.0240 (8)	0.0377 (10)	0.0241 (8)	0.0032 (7)	0.0125 (7)	0.0015 (7)
C4	0.0398 (11)	0.0415 (13)	0.0271 (10)	−0.0058 (9)	0.0139 (9)	−0.0004 (9)
C5	0.0353 (11)	0.0472 (14)	0.0338 (11)	−0.0078 (10)	0.0155 (9)	−0.0015 (10)

Geometric parameters (Å, º)

O1—N1	1.299 (2)	N4—H3	0.95 (3)
O2—C3	1.239 (2)	N4—H4	0.89 (3)
N1—C1	1.311 (2)	N4—H5	0.94 (3)
N2—C2	1.151 (3)	C4—C5	1.530 (3)
N3—C3	1.337 (3)	C4—H4A	1.033 (19)
N3—H1	0.84 (2)	C4—H4B	1.055 (19)
N3—H2	0.82 (2)	C5—C5^i	1.523 (5)
C1—C2	1.436 (3)	C5—H5A	1.054 (19)
C1—C3	1.482 (3)	C5—H5B	1.06 (2)
N4—C4	1.493 (3)
O1—N1—C1	117.74 (16)	H3—N4—H5	107 (2)
C3—N3—H1	118.4 (19)	H4—N4—H5	106 (2)
C3—N3—H2	115 (2)	N4—C4—C5	112.84 (18)
H1—N3—H2	127 (3)	N4—C4—H4A	106.9 (15)
N1—C1—C2	123.02 (17)	C5—C4—H4A	113.0 (15)
N1—C1—C3	118.77 (17)	N4—C4—H4B	105.3 (16)
C2—C1—C3	118.17 (16)	C5—C4—H4B	109.1 (15)
N2—C2—C1	177.8 (2)	H4A—C4—H4B	109 (2)
O2—C3—N3	123.71 (19)	C5^i—C5—C4	112.2 (2)
O2—C3—C1	119.78 (17)	C5^i—C5—H5A	106.6 (16)
N3—C3—C1	116.52 (17)	C4—C5—H5A	111.4 (16)
C4—N4—H3	112.9 (17)	C5^i—C5—H5B	106.9 (19)
C4—N4—H4	111.0 (16)	C4—C5—H5B	112.9 (19)
H3—N4—H4	105 (2)	H5A—C5—H5B	107 (3)
C4—N4—H5	113.9 (17)
O1—N1—C1—C2	−0.5 (3)	N1—C1—C3—N3	2.2 (3)
O1—N1—C1—C3	−178.10 (17)	C2—C1—C3—N3	−175.57 (18)
N1—C1—C3—O2	−177.87 (18)	N4—C4—C5—C5^i	−63.72 (19)
C2—C1—C3—O2	4.4 (3)

Symmetry code: (i) −x+1, y, −z+1/2.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N4—H3···O1	0.95 (3)	1.84 (3)	2.770 (2)	164 (2)
N4—H4···O1^ii	0.89 (3)	1.92 (3)	2.765 (2)	156 (2)
N4—H5···N2^iii	0.94 (3)	2.29 (3)	3.157 (3)	152 (2)
N4—H5···O2^iv	0.94 (3)	2.40 (3)	2.959 (2)	118 (2)
N3—H1···O2^v	0.84 (2)	2.07 (2)	2.910 (2)	174 (3)
C4—H4A···O2^vi	1.03 (2)	2.55 (2)	3.535 (3)	158 (2)

Symmetry codes: (ii) −x+1/2, −y+1/2, −z; (iii) x+1/2, y−1/2, z; (iv) −x+1/2, y−1/2, −z+1/2; (v) −x+1/2, −y+1/2, −z+1; (vi) −x+1/2, y+1/2, −z+1/2.

Hexane-1,6-bis(aminium) bis(nitrosocarbamoylcyanomethanide) (4)

Crystal data

C6H18N2^2+·2C3H2N3O2^−	F(000) = 364
Mr = 342.37	Dx = 1.358 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
a = 4.6121 (2) Å	Cell parameters from 10650 reflections
b = 16.8608 (7) Å	θ = 3.1–27.9°
c = 10.7931 (7) Å	µ = 0.11 mm^−1
β = 93.853 (3)°	T = 173 K
V = 837.41 (7) Å^3	Prism, yellow
Z = 2	0.36 × 0.22 × 0.12 mm

Data collection

Bruker APEXII CCD diffractometer	1426 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.055
Graphite monochromator	θmax = 27.9°, θmin = 3.1°
φ and ω scans	h = −6→6
10650 measured reflections	k = −21→22
1986 independent reflections	l = −14→13

Refinement

Refinement on F^2	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.049	Hydrogen site location: difference Fourier map
wR(F^2) = 0.121	All H-atom parameters refined
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0546P)^2 + 0.1378P] where P = (Fo^2 + 2Fc^2)/3
1986 reflections	(Δ/σ)max < 0.001
153 parameters	Δρmax = 0.37 e Å^−3
0 restraints	Δρmin = −0.22 e Å^−3

Special details

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Ų)

	x	y	z	Uiso*/Ueq
O1	0.7069 (3)	0.07305 (7)	0.55695 (11)	0.0277 (3)
O2	0.4448 (3)	0.29146 (7)	0.77739 (12)	0.0294 (3)
N1	0.5527 (3)	0.10502 (8)	0.64100 (13)	0.0238 (3)
N2	0.9065 (4)	0.26530 (10)	0.52539 (16)	0.0379 (4)
N3	0.2353 (4)	0.17321 (10)	0.81457 (16)	0.0331 (4)
C1	0.5723 (4)	0.18219 (9)	0.65637 (15)	0.0205 (4)
C2	0.7544 (4)	0.22996 (10)	0.58450 (16)	0.0241 (4)
C3	0.4106 (4)	0.22024 (10)	0.75425 (16)	0.0229 (4)
N4	1.1324 (3)	0.08464 (9)	0.38570 (14)	0.0207 (3)
C4	0.9393 (4)	0.06561 (11)	0.27341 (16)	0.0229 (4)
C5	1.1114 (4)	0.03861 (11)	0.16663 (16)	0.0225 (4)
C6	0.9178 (4)	0.01911 (10)	0.05096 (15)	0.0224 (4)
H1	0.137 (5)	0.1922 (14)	0.877 (3)	0.058 (7)*
H2	0.223 (4)	0.1257 (14)	0.791 (2)	0.041 (6)*
H3	1.016 (4)	0.0986 (11)	0.4508 (19)	0.029 (5)*
H4	1.230 (5)	0.0398 (13)	0.4093 (18)	0.035 (5)*
H5	1.247 (4)	0.1238 (12)	0.3683 (19)	0.031 (5)*
H4A	0.808 (4)	0.0237 (10)	0.2982 (16)	0.023 (5)*
H4B	0.827 (4)	0.1103 (11)	0.2539 (17)	0.023 (5)*
H5A	1.230 (4)	−0.0060 (11)	0.1934 (17)	0.028 (5)*
H5B	1.238 (4)	0.0800 (12)	0.1474 (19)	0.033 (5)*
H6A	0.823 (4)	0.0668 (10)	0.0210 (16)	0.017 (4)*
H6B	0.767 (4)	−0.0159 (11)	0.0700 (17)	0.029 (5)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0325 (7)	0.0256 (6)	0.0259 (7)	0.0020 (5)	0.0096 (6)	−0.0039 (5)
O2	0.0338 (7)	0.0212 (6)	0.0346 (7)	−0.0008 (5)	0.0114 (6)	−0.0059 (5)
N1	0.0233 (8)	0.0257 (7)	0.0225 (8)	0.0033 (6)	0.0030 (6)	−0.0017 (6)
N2	0.0450 (10)	0.0360 (9)	0.0344 (10)	−0.0035 (8)	0.0159 (8)	0.0006 (7)
N3	0.0426 (10)	0.0236 (8)	0.0355 (10)	−0.0030 (7)	0.0198 (8)	−0.0037 (7)
C1	0.0214 (9)	0.0196 (8)	0.0207 (9)	−0.0005 (6)	0.0029 (7)	0.0006 (6)
C2	0.0285 (9)	0.0212 (8)	0.0230 (9)	0.0037 (7)	0.0060 (8)	−0.0042 (7)
C3	0.0223 (9)	0.0242 (9)	0.0224 (9)	0.0013 (7)	0.0034 (7)	0.0012 (7)
N4	0.0253 (8)	0.0186 (7)	0.0189 (8)	−0.0004 (6)	0.0063 (6)	−0.0013 (6)
C4	0.0219 (9)	0.0244 (9)	0.0224 (9)	0.0012 (7)	0.0019 (7)	−0.0020 (7)
C5	0.0233 (9)	0.0247 (9)	0.0196 (9)	0.0010 (7)	0.0014 (7)	−0.0021 (7)
C6	0.0243 (9)	0.0226 (9)	0.0202 (9)	0.0007 (7)	0.0004 (7)	0.0003 (7)

Geometric parameters (Å, º)

O1—N1	1.3061 (18)	N4—H4	0.91 (2)
O2—C3	1.234 (2)	N4—H5	0.87 (2)
N1—C1	1.314 (2)	C4—C5	1.513 (2)
N2—C2	1.147 (2)	C4—H4A	0.980 (19)
N3—C3	1.333 (2)	C4—H4B	0.932 (18)
N3—H1	0.90 (3)	C5—C6	1.521 (2)
N3—H2	0.84 (2)	C5—H5A	0.963 (19)
C1—C2	1.429 (2)	C5—H5B	0.94 (2)
C1—C3	1.480 (2)	C6—C6^i	1.521 (3)
N4—C4	1.490 (2)	C6—H6A	0.961 (17)
N4—H3	0.94 (2)	C6—H6B	0.94 (2)
O1—N1—C1	117.41 (14)	N4—C4—H4A	106.3 (10)
C3—N3—H1	120.6 (16)	C5—C4—H4A	111.0 (10)
C3—N3—H2	116.9 (15)	N4—C4—H4B	107.7 (11)
H1—N3—H2	123 (2)	C5—C4—H4B	112.6 (11)
N1—C1—C2	121.83 (15)	H4A—C4—H4B	107.3 (15)
N1—C1—C3	119.07 (14)	C4—C5—C6	112.40 (15)
C2—C1—C3	119.06 (14)	C4—C5—H5A	108.8 (11)
N2—C2—C1	177.00 (18)	C6—C5—H5A	111.6 (11)
O2—C3—N3	123.57 (17)	C4—C5—H5B	108.1 (12)
O2—C3—C1	120.19 (15)	C6—C5—H5B	108.5 (12)
N3—C3—C1	116.23 (16)	H5A—C5—H5B	107.2 (16)
C4—N4—H3	108.7 (11)	C6^i—C6—C5	113.04 (18)
C4—N4—H4	107.8 (13)	C6^i—C6—H6A	110.5 (10)
H3—N4—H4	107.1 (17)	C5—C6—H6A	108.9 (10)
C4—N4—H5	109.0 (13)	C6^i—C6—H6B	107.6 (11)
H3—N4—H5	110.8 (18)	C5—C6—H6B	110.9 (11)
H4—N4—H5	113.3 (19)	H6A—C6—H6B	105.6 (15)
N4—C4—C5	111.65 (15)
O1—N1—C1—C2	0.0 (2)	N1—C1—C3—N3	−5.1 (2)
O1—N1—C1—C3	−177.46 (14)	C2—C1—C3—N3	177.31 (16)
N1—C1—C3—O2	173.90 (16)	N4—C4—C5—C6	−179.84 (14)
C2—C1—C3—O2	−3.6 (2)	C4—C5—C6—C6^i	−171.84 (18)

Symmetry code: (i) −x+2, −y, −z.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N4—H3···O1	0.94 (2)	1.94 (2)	2.792 (2)	149.9 (16)
N4—H4···O1^ii	0.91 (2)	1.96 (2)	2.8178 (19)	158.2 (18)
N4—H5···O2^iii	0.87 (2)	1.99 (2)	2.834 (2)	162.3 (18)
N3—H1···N2^iv	0.90 (3)	2.10 (3)	3.003 (3)	179 (2)
C4—H4B···O2^v	0.932 (18)	2.443 (19)	3.321 (2)	156.9 (15)
C5—H5A···N1^ii	0.963 (19)	2.597 (19)	3.485 (2)	153.4 (15)

Symmetry codes: (ii) −x+2, −y, −z+1; (iii) x+1, −y+1/2, z−1/2; (iv) x−1, −y+1/2, z+1/2; (v) x, −y+1/2, z−1/2.