C-meso-(3,5,7,7,10,12,12,14-Octa­methyl-1,4,8,11-tetra­azacyclo­tetra­deca-4,11-diene)nickel(II) bis­(thio­cyanate)

The title complex, (1RS,3SR,8SR,10RS-3,5,7,7,10,12,12,14-octa­methyl-1,4,8,11-tetraazacyclotetra­deca-4,11-diene-κ⁴N^1,4,8,11)­nickel(II) bis­(thio­cyanate), [Ni(C₁₈H₃₆N₄)](NCS)₂, has a centrosymmetrical square-planar singlet ground state nickel(II) cation, with Ni—N_amine = 1.940 (1) Å and Ni—N_imine = 1.921 (1) Å. The C-3 methyl substituent is axially oriented. The thio­cyanate N atom is hydrogen bonded to the NH group.

Key indicators

• Single-crystal X-ray study
• T = 273 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.023
• wR factor = 0.061
• Data-to-parameter ratio = 18.0

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT042_ALERT_1_C Calc. and Rep. MoietyFormula Strings Differ ....          ?
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Ni1    -   N1      ..       5.88 su
PLAT232_ALERT_2_C Hirshfeld Test Diff (M-X)  Ni1    -   N4      ..       6.59 su
PLAT412_ALERT_2_C Short Intra XH3 .. XHn     H3     ..  H51A    ..       1.87 Ang.

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   4 ALERT level C = Check and explain
   0 ALERT level G = General alerts; check

   1 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 ALERT type 2 Indicator that the structure model may be wrong or deficient
   0 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion

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S1. Comment

The azamacrocyle cations C-meso- and C-rac-(Me₈[14]diene)nickel(II) (Me₈[14]diene = 3,5,7,7,10,12,12,14-octamethyl-1,4,8,11- tetraazacyclotetradeca-4,11-diene), formed by reaction of tris(rac-propane-1,2-diamine)nickel(II) compounds with acetone, were separated by fractional crystallization, see the Scheme (Blight & Curtis, 1962; Curtis, 1973). Compounds of the C-meso isomer can also be prepared from salts [H₂(C-meso-Me₈[14]diene)]X₂, formed by reaction of mono-protonated salts [H(rac-propane-1,2-diamine)]X, X⁻ = ClO₄⁻, Br⁻, NCS⁻, etc, with acetone (Curtis, 1973).

The structure of yellow, singlet ground state, [Ni(C-meso-Me₈[14]diene)](CNS)₂, is reported here. It is comprised of a centrosymmetrical square-planar cation [Ni(C-meso-Me₈[14]diene)]²⁺ with the thiocyanate ion located off the tetragonal axis (with closest approach Ni—N_NCS = 4.054 Å) and hydrogen bonded to the N—H group. The closest axial approach to the nickel is by the imine methyl group of another cation with Ni···H51B = 3.68 Å.

The nickel(II) ion is coordinated by the four N-atoms of the macrocycle, with the Ni—N distance 0.029 (2) Å shorter for the imine than the secondary amine N atom, see Fig. 1 and Table 1. The propane-1,2-diamine residue methyl substituent is at ring position 3, adjacent to the imine N atom, axially oriented on the same side of the molecular plane as the N1—H atom, on the opposite side to the axial component of the gem dimethyl group, (C72). Displacements of atoms from the NiN₄ plane are: C2, −0.476 (2); C3, 0.1503 (2); C31, 1.627 (2); C5, −0.068 (2); C51, −0.109 (3); C6, −0.059 (3); C7, 0.703 (2); C71, 0.612 (3); C72, 2.167 (2) Å.

The structurally characterized compound of the C-rac isomeric cation, [Ni(C-rac-Me₈[14]diene)](ClO₄)₂, (Swann, et al., 1972) has approximate twofold symmetry, with the C3 and C10 methyl substituents axially oriented on the same side of the molecular plane, with the axially oriented components of the C7 and C14 gem-dimethyl groups oriented towards the other side of the plane, with mean distances Ni—N_amine = 1.93 (1) and Ni—N_imine = 1.89 (1) Å.

The compound [Cu(C-meso-Me₈[14]diene)](ClO₄)₂·2H₂O (Hazari et al., 1999) has the same configuration and similar conformation of the macrocycle to the title compound, with Cu—N_amine = 2.010 (2), Cu—N_imine = 1.985 (3) Å, with perchlorate oxygen atoms in approximate axial sites with Cu—O = 2.779 (3) Å.

The structures of thiocyanate complexes of (5,7,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradeca-5,11- diene)nickel(II), [Ni(Me₆[14]diene)]²⁺, (Curtis & Curtis, 1966) have been determined. The structure of N-meso-[Ni(Me₆[14]diene)](SCN)₂ (Hanic & Miklos, 1972) is similar to that of the title complex, with mean distances Ni—N_amine = 1.92 and Ni—N_imine = 1.88 Å, while N-rac-[Ni(Me₆[14]diene)(NCS)]ClO₄ (Shen et al., 1999) has an unusual singlet ground state five-coordinate structure with mean distances Ni—N_amine = 2.045 (8), Ni—N_imine = 2.015 (8) and Ni—N_NCS = 2.221 (5) Å.

The structure of trans-[Co(C-meso-Me₈[14]diene)Cl₂]ClO₄ (Lu et al., 1992) and the space group and cell parameters of [Ni(C-meso-Me₈[14]diene)](ClO₄)₂ (Curtis et al., 1969) have been reported.

S2. Experimental

Excess of NaCNS was added to a hot saturated aqueous solution of orange [Ni(C-meso-L)](ClO₄)₂. (What is L?) The yellow thiocyanate salt was filtered off from the cold solution and recrystallized from methanol.

S3. Refinement

All H atoms were placed in calculated positions, with C—H = 0.96 Å and were included in the least squares refinement as riding on their carrier atoms, with U_iso(H) = 1.2U_eq of the corresponding carrier atom.

Computing details

Data collection: SMART (Siemens, 1995); cell refinement: SAINT (Siemens, 1995); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1990); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: ORTEP-3.2 (Farrugia, 1997); software used to prepare material for publication: SHELXL97.

Figures

Fig. 1. [Ni(C-meso-Me8[14]diene))(NCS)2 drawn with displacement ellipsoids at 50% probability level, with H atoms shown as circles of arbitrary radii.

(1RS,3SR,8SR,10RS-3,5,7,7,10,12,12,14-octamethyl-1,4,8,11- tetraazacyclotetradeca-4,11-diene-κ⁴N^1,4,8,11)nickel(II) bis(thiocyanate)

Crystal data

[Ni(C18H36N4)](NCS)2	Z = 1
Mr = 483.38	F(000) = 258
Triclinic, P1	Dx = 1.412 Mg m^−3
Hall symbol: -P 1	Mo Kα radiation, λ = 0.71073 Å
a = 7.3383 (6) Å	Cell parameters from 2683 reflections
b = 8.0955 (6) Å	θ = 2.8–28.3°
c = 10.2042 (8) Å	µ = 1.06 mm^−1
α = 69.917 (1)°	T = 273 K
β = 86.852 (1)°	Block, yellow
γ = 88.965 (1)°	0.40 × 0.20 × 0.18 mm
V = 568.48 (8) Å^3

Data collection

Bruker SMART CCD area-detector diffractometer	2393 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.008
Graphite monochromator	θmax = 28.4°, θmin = 2.1°
ϕ and ω scans	h = −9→9
3335 measured reflections	k = −8→10
2472 independent reflections	l = −13→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)] = 0.023	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.061	H-atom parameters constrained
S = 1.06	w = 1/[σ^2(Fo^2) + (0.0311P)^2 + 0.291P] where P = (Fo^2 + 2Fc^2)/3
2472 reflections	(Δ/σ)max = 0.001
137 parameters	Δρmax = 0.38 e Å^−3
0 restraints	Δρmin = −0.25 e Å^−3

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
Ni1	0.5000	0.5000	0.5000	0.00971 (8)
N1	0.50725 (14)	0.47718 (14)	0.69517 (11)	0.0120 (2)
H1	0.5779	0.5674	0.6971	0.014*
N4	0.27883 (15)	0.63089 (14)	0.49926 (11)	0.0128 (2)
C5	0.16839 (17)	0.69536 (17)	0.40027 (14)	0.0136 (2)
C6	0.20809 (18)	0.68678 (18)	0.25715 (14)	0.0153 (3)
H6A	0.1484	0.7858	0.1906	0.018*
H6B	0.1526	0.5805	0.2538	0.018*
C2	0.32061 (18)	0.51070 (18)	0.74570 (14)	0.0155 (3)
H2A	0.3268	0.5375	0.8310	0.019*
H2B	0.2448	0.4072	0.7654	0.019*
C7	0.40883 (18)	0.68814 (17)	0.20850 (13)	0.0135 (3)
C51	−0.00540 (18)	0.79061 (19)	0.41374 (14)	0.0180 (3)
H51A	−0.0539	0.7461	0.5087	0.027*
H51B	−0.0926	0.7725	0.3532	0.027*
H51C	0.0192	0.9141	0.3880	0.027*
C31	0.3210 (2)	0.84069 (18)	0.62284 (15)	0.0192 (3)
H31A	0.4514	0.8367	0.6102	0.029*
H31B	0.2893	0.8649	0.7070	0.029*
H31C	0.2731	0.9317	0.5445	0.029*
C72	0.5068 (2)	0.85158 (18)	0.21209 (15)	0.0180 (3)
H72A	0.5170	0.8441	0.3074	0.027*
H72B	0.4385	0.9547	0.1636	0.027*
H72C	0.6265	0.8585	0.1676	0.027*
C71	0.41348 (19)	0.68588 (19)	0.05837 (13)	0.0172 (3)
H71A	0.5373	0.6976	0.0208	0.026*
H71B	0.3422	0.7818	0.0017	0.026*
H71C	0.3639	0.5768	0.0588	0.026*
C3	0.24005 (18)	0.66384 (17)	0.63368 (13)	0.0147 (3)
H3	0.1077	0.6660	0.6521	0.018*
N20	0.76296 (17)	0.74108 (17)	0.72386 (13)	0.0221 (3)
C20	0.83366 (18)	0.77659 (18)	0.81043 (14)	0.0164 (3)
S20	0.93355 (5)	0.83066 (5)	0.93031 (4)	0.02264 (10)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
Ni1	0.01007 (12)	0.01126 (12)	0.00886 (12)	0.00289 (8)	−0.00114 (8)	−0.00484 (9)
N1	0.0118 (5)	0.0135 (5)	0.0116 (5)	0.0027 (4)	−0.0011 (4)	−0.0054 (4)
N4	0.0131 (5)	0.0148 (5)	0.0115 (5)	0.0025 (4)	−0.0003 (4)	−0.0060 (4)
C5	0.0132 (6)	0.0133 (6)	0.0147 (6)	0.0012 (5)	−0.0004 (5)	−0.0054 (5)
C6	0.0143 (6)	0.0197 (6)	0.0130 (6)	0.0059 (5)	−0.0037 (5)	−0.0069 (5)
C2	0.0134 (6)	0.0207 (7)	0.0128 (6)	0.0037 (5)	0.0006 (5)	−0.0067 (5)
C7	0.0152 (6)	0.0152 (6)	0.0102 (6)	0.0039 (5)	−0.0023 (5)	−0.0044 (5)
C51	0.0152 (6)	0.0232 (7)	0.0153 (6)	0.0071 (5)	−0.0023 (5)	−0.0065 (5)
C31	0.0221 (7)	0.0176 (7)	0.0213 (7)	0.0045 (5)	−0.0029 (6)	−0.0108 (6)
C72	0.0221 (7)	0.0141 (6)	0.0173 (6)	0.0009 (5)	−0.0006 (5)	−0.0047 (5)
C71	0.0198 (6)	0.0212 (7)	0.0105 (6)	0.0049 (5)	−0.0018 (5)	−0.0052 (5)
C3	0.0145 (6)	0.0177 (6)	0.0133 (6)	0.0031 (5)	0.0008 (5)	−0.0075 (5)
N20	0.0209 (6)	0.0253 (6)	0.0234 (6)	−0.0027 (5)	0.0022 (5)	−0.0127 (5)
C20	0.0136 (6)	0.0151 (6)	0.0186 (6)	0.0012 (5)	0.0033 (5)	−0.0043 (5)
S20	0.02041 (18)	0.0299 (2)	0.01789 (18)	−0.00037 (14)	−0.00455 (14)	−0.00796 (15)

Geometric parameters (Å, º)

Ni1—N4	1.921 (1)	C7—C72	1.5297 (18)
Ni1—N4^i	1.9212 (11)	C7—C71	1.5368 (17)
Ni1—N1	1.940 (1)	C51—H51A	0.9600
Ni1—N1^i	1.9395 (11)	C51—H51B	0.9600
N1—C2	1.4901 (16)	C51—H51C	0.9600
N1—C7^i	1.5066 (16)	C31—C3	1.5263 (19)
N1—H1	0.9100	C31—H31A	0.9600
N4—C5	1.289 (2)	C31—H31B	0.9600
N4—C3	1.4963 (16)	C31—H31C	0.9600
C5—C6	1.4983 (18)	C72—H72A	0.9600
C5—C51	1.5027 (18)	C72—H72B	0.9600
C6—C7	1.5275 (18)	C72—H72C	0.9600
C6—H6A	0.9700	C71—H71A	0.9600
C6—H6B	0.9700	C71—H71B	0.9600
C2—C3	1.5058 (18)	C71—H71C	0.9600
C2—H2A	0.9700	C3—H3	0.9800
C2—H2B	0.9700	N20—C20	1.167 (2)
C7—N1^i	1.5066 (16)	C20—S20	1.644 (2)
N4—Ni1—N4^i	180.00 (7)	C6—C7—C71	106.91 (10)
N4—Ni1—N1	86.05 (5)	C72—C7—C71	110.20 (11)
N4^i—Ni1—N1	93.95 (5)	C5—C51—H51A	109.5
N4—Ni1—N1^i	93.95 (5)	C5—C51—H51B	109.5
N4^i—Ni1—N1^i	86.05 (5)	H51A—C51—H51B	109.5
N1—Ni1—N1^i	180.0	C5—C51—H51C	109.5
C2—N1—C7^i	112.68 (10)	H51A—C51—H51C	109.5
C2—N1—Ni1	108.42 (8)	H51B—C51—H51C	109.5
C7^i—N1—Ni1	117.01 (8)	C3—C31—H31A	109.5
C2—N1—H1	106.0	C3—C31—H31B	109.5
C7^i—N1—H1	106.0	H31A—C31—H31B	109.5
Ni1—N1—H1	106.0	C3—C31—H31C	109.5
C5—N4—C3	118.29 (11)	H31A—C31—H31C	109.5
C5—N4—Ni1	129.2 (1)	H31B—C31—H31C	109.5
C3—N4—Ni1	112.44 (8)	C7—C72—H72A	109.5
N4—C5—C6	121.8 (1)	C7—C72—H72B	109.5
N4—C5—C51	124.4 (1)	H72A—C72—H72B	109.5
C6—C5—C51	113.72 (11)	C7—C72—H72C	109.5
C5—C6—C7	116.80 (11)	H72A—C72—H72C	109.5
C5—C6—H6A	108.1	H72B—C72—H72C	109.5
C7—C6—H6A	108.1	C7—C71—H71A	109.5
C5—C6—H6B	108.1	C7—C71—H71B	109.5
C7—C6—H6B	108.1	H71A—C71—H71B	109.5
H6A—C6—H6B	107.3	C7—C71—H71C	109.5
N1—C2—C3	108.32 (10)	H71A—C71—H71C	109.5
N1—C2—H2A	110.0	H71B—C71—H71C	109.5
C3—C2—H2A	110.0	N4—C3—C2	106.12 (10)
N1—C2—H2B	110.0	N4—C3—C31	109.63 (11)
C3—C2—H2B	110.0	C2—C3—C31	113.20 (11)
H2A—C2—H2B	108.4	N4—C3—H3	109.3
N1^i—C7—C6	106.76 (10)	C2—C3—H3	109.3
N1^i—C7—C72	110.97 (11)	C31—C3—H3	109.3
C6—C7—C72	111.31 (11)	N20—C20—S20	178.9 (1)
N1^i—C7—C71	110.57 (10)

Symmetry code: (i) −x+1, −y+1, −z+1.

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1···N20	0.91	2.07	2.968 (2)	171