Potassium (1-methoxy-carbonyl-2-methyl-prop-2-en-2-yl-idene)azinate.

In the title compound, K(+)·C(6)H(8)NO(4) (-), the K(+) cations have a coordination number of seven and are surrounded by four bidentate azinate anions. The methyl-ene groups of the anions are always directed towards the coordinated potassium cations. The N-C-C-C torsion angle is 101.2 (2)°. The orthogonal non-conjugated nature of the salt confirms the supposed geometry and reactivity of this compound.

Related literature

For a short overview of peptidomimetics, see: Grauer et al. (2009 ▶); Vagner et al. (2008 ▶); Wu et al. (2008 ▶). For the synthesis of peptidomimetics, amino-acid-based building blocks play a key role in the assembly of these structures, see: Kemp, Boyd & Muendel (1991 ▶); Kemp, Curran et al. (1991 ▶); Beal et al. (2000 ▶); Kühne et al. (2008 ▶). A known deprotonation/proton­ation sequence (Bouveault & Wahl, 1901 ▶) was used in the synthesis of the title compound. The protonation of the title compound occurs exclusively at the α-position and no proton­ation of the methyl­ene group was observed (Baldwin et al., 1977 ▶).

Experimental

Crystal data

K+·C6H8NO4 −

M = 197.23

Monoclinic,

a = 23.9269 (13) Å

b = 5.2909 (2) Å

c = 14.2510 (7) Å

β = 113.361 (2)°

V = 1656.21 (14) Å3

Z = 8

Mo Kα radiation

μ = 0.62 mm−1

T = 100 K

0.20 × 0.15 × 0.03 mm

Data collection

Nonius KappaCCD diffractometer

6264 measured reflections

1810 independent reflections

1416 reflections with I > 2σ(I)

R int = 0.041

Refinement

R[F 2 > 2σ(F 2)] = 0.028

wR(F 2) = 0.061

S = 1.01

1810 reflections

111 parameters

H-atom parameters constrained

Δρmax = 0.31 e Å−3

Δρmin = −0.27 e Å−3

Data collection: COLLECT (Hooft, 1998 ▶); cell refinement: DENZO (Otwinowski & Minor, 1997 ▶); data reduction: DENZO; program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SCHAKAL99 (Keller, 1999 ▶); software used to prepare material for publication: PLATON (Spek, 2009 ▶), publCIF (Westrip, 2010 ▶) and ORTEP (Davenport et al., 1999 ▶).

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536810010159/jj2024sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536810010159/jj2024Isup2.hkl

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

K+·C6H8NO4−	F(000) = 816
Mr = 197.23	Dx = 1.582 Mg m−3
Monoclinic, Cm2/c	Melting point: 180.7(10) K
Hall symbol: -C 2yc	Mo Kα radiation, λ = 0.71073 Å
a = 23.9269 (13) Å	Cell parameters from 6264 reflections
b = 5.2909 (2) Å	θ = 1.9–27.0°
c = 14.2510 (7) Å	µ = 0.62 mm−1
β = 113.361 (2)°	T = 100 K
V = 1656.21 (14) Å3	Platlet, colourless
Z = 8	0.20 × 0.15 × 0.03 mm

Nonius KappaCCD diffractometer	1416 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.041
graphite	θmax = 27.0°, θmin = 1.9°
Phi/ω–Scans scans	h = −30→30
6264 measured reflections	k = −6→6
1810 independent reflections	l = −18→18

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)] = 0.028	Hydrogen site location: inferred from neighbouring sites
wR(F2) = 0.061	H-atom parameters constrained
S = 1.01	w = 1/[σ2(Fo2) + (0.0266P)2] where P = (Fo2 + 2Fc2)/3
1810 reflections	(Δ/σ)max = 0.001
111 parameters	Δρmax = 0.31 e Å−3
0 restraints	Δρmin = −0.27 e Å−3

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.

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.

	x	y	z	Uiso*/Ueq
K1	0.269013 (15)	−0.06555 (6)	0.11206 (2)	0.01586 (11)
O1	0.22159 (5)	0.42337 (19)	0.06333 (8)	0.0183 (3)
O2	0.20272 (5)	0.26997 (19)	0.19103 (8)	0.0172 (2)
O3	0.15057 (5)	0.81224 (18)	−0.04385 (8)	0.0194 (3)
O4	0.07200 (5)	0.87761 (19)	0.00265 (8)	0.0191 (3)
N1	0.19003 (6)	0.4306 (2)	0.11777 (9)	0.0144 (3)
C1	0.14436 (7)	0.5975 (3)	0.10141 (11)	0.0142 (3)
C2	0.12553 (7)	0.7664 (3)	0.01413 (12)	0.0155 (3)
C3	0.04879 (8)	1.0606 (3)	−0.07901 (12)	0.0213 (4)
H3A	0.0089	1.1211	−0.0844	0.032*
H3B	0.0446	0.9813	−0.1436	0.032*
H3C	0.0771	1.2034	−0.0644	0.032*
C4	0.11349 (7)	0.5958 (3)	0.17409 (12)	0.0164 (3)
C5	0.12805 (8)	0.7705 (3)	0.24651 (12)	0.0221 (4)
H5A	0.1578	0.8947	0.2516	0.027*
H5B	0.1087	0.7716	0.2933	0.027*
C6	0.06556 (8)	0.3977 (3)	0.15837 (14)	0.0248 (4)
H6A	0.0312	0.4272	0.0930	0.037*
H6B	0.0514	0.4067	0.2141	0.037*
H6C	0.0828	0.2300	0.1577	0.037*

	U11	U22	U33	U12	U13	U23
K1	0.01789 (19)	0.0171 (2)	0.01396 (19)	0.00072 (15)	0.00778 (15)	−0.00055 (14)
O1	0.0217 (6)	0.0208 (6)	0.0198 (6)	0.0039 (5)	0.0160 (5)	0.0020 (5)
O2	0.0228 (6)	0.0153 (6)	0.0153 (6)	0.0030 (5)	0.0095 (5)	0.0046 (5)
O3	0.0205 (6)	0.0232 (6)	0.0190 (6)	0.0044 (5)	0.0125 (5)	0.0050 (5)
O4	0.0167 (6)	0.0236 (6)	0.0204 (6)	0.0070 (5)	0.0108 (5)	0.0086 (5)
N1	0.0175 (7)	0.0143 (7)	0.0130 (7)	−0.0020 (6)	0.0076 (6)	−0.0014 (6)
C1	0.0142 (8)	0.0147 (8)	0.0156 (8)	0.0008 (6)	0.0080 (7)	0.0004 (6)
C2	0.0160 (9)	0.0148 (8)	0.0159 (8)	−0.0013 (7)	0.0065 (7)	−0.0038 (7)
C3	0.0198 (9)	0.0241 (9)	0.0201 (9)	0.0057 (8)	0.0082 (8)	0.0083 (7)
C4	0.0159 (8)	0.0185 (9)	0.0169 (9)	0.0066 (7)	0.0086 (7)	0.0053 (7)
C5	0.0261 (10)	0.0238 (9)	0.0207 (9)	0.0074 (7)	0.0138 (8)	0.0046 (7)
C6	0.0237 (10)	0.0247 (9)	0.0320 (10)	0.0009 (7)	0.0175 (9)	0.0046 (8)

K1—O1i	2.7036 (10)	O4—C2	1.3591 (18)
K1—O2ii	2.7539 (11)	O4—C3	1.4447 (18)
K1—O3i	2.7988 (11)	N1—C1	1.3516 (19)
K1—O1	2.7994 (11)	N1—K1iv	3.2874 (12)
K1—O2	2.8896 (10)	C1—C2	1.451 (2)
K1—O3iii	2.8970 (12)	C1—C4	1.4917 (19)
K1—O1iii	2.9080 (11)	C1—K1iv	3.4260 (15)
K1—C5ii	3.0584 (16)	C2—K1iv	3.2747 (16)
K1—N1	3.2542 (13)	C3—H3A	0.9800
K1—C2iii	3.2747 (16)	C3—H3B	0.9800
K1—N1iii	3.2874 (12)	C3—H3C	0.9800
K1—C4ii	3.3355 (16)	C4—C5	1.325 (2)
O1—N1	1.2799 (14)	C4—C6	1.503 (2)
O1—K1i	2.7036 (10)	C4—K1v	3.3355 (16)
O1—K1iv	2.9081 (11)	C5—K1v	3.0583 (16)
O2—N1	1.2856 (15)	C5—H5A	0.9500
O2—K1v	2.7539 (11)	C5—H5B	0.9500
O3—C2	1.2219 (16)	C6—H6A	0.9800
O3—K1i	2.7989 (11)	C6—H6B	0.9800
O3—K1iv	2.8970 (12)	C6—H6C	0.9800
O1i—K1—O2ii	162.38 (3)	N1—K1—C4ii	93.33 (4)
O1i—K1—O3i	59.21 (3)	C2iii—K1—C4ii	145.11 (4)
O2ii—K1—O3i	106.36 (3)	N1iii—K1—C4ii	118.00 (3)
O1i—K1—O1	71.80 (3)	N1—O1—K1i	146.87 (9)
O2ii—K1—O1	117.16 (3)	N1—O1—K1	98.95 (7)
O3i—K1—O1	127.70 (3)	K1i—O1—K1	108.20 (3)
O1i—K1—O2	116.67 (3)	N1—O1—K1iv	95.49 (7)
O2ii—K1—O2	75.42 (2)	K1i—O1—K1iv	78.14 (3)
O3i—K1—O2	168.78 (3)	K1—O1—K1iv	135.94 (4)
O1—K1—O2	45.40 (3)	N1—O2—K1v	120.14 (8)
O1i—K1—O3iii	76.57 (3)	N1—O2—K1	94.53 (7)
O2ii—K1—O3iii	118.77 (3)	K1v—O2—K1	129.79 (4)
O3i—K1—O3iii	103.16 (3)	C2—O3—K1i	136.99 (9)
O1—K1—O3iii	80.73 (3)	C2—O3—K1iv	96.80 (9)
O2—K1—O3iii	85.11 (3)	K1i—O3—K1iv	76.84 (3)
O1i—K1—O1iii	101.86 (3)	C2—O4—C3	115.46 (12)
O2ii—K1—O1iii	82.21 (3)	O1—N1—O2	117.81 (11)
O3i—K1—O1iii	74.94 (3)	O1—N1—C1	123.09 (12)
O1—K1—O1iii	135.94 (4)	O2—N1—C1	119.10 (12)
O2—K1—O1iii	116.22 (3)	O1—N1—K1	58.18 (6)
O3iii—K1—O1iii	55.87 (3)	O2—N1—K1	62.27 (7)
O1i—K1—C5ii	96.14 (4)	C1—N1—K1	163.88 (10)
O2ii—K1—C5ii	72.78 (4)	O1—N1—K1iv	61.71 (6)
O3i—K1—C5ii	90.87 (4)	O2—N1—K1iv	127.10 (9)
O1—K1—C5ii	76.55 (4)	C1—N1—K1iv	84.21 (8)
O2—K1—C5ii	79.00 (4)	K1—N1—K1iv	107.96 (4)
O3iii—K1—C5ii	157.29 (4)	N1—C1—C2	120.36 (13)
O1iii—K1—C5ii	146.51 (4)	N1—C1—C4	117.74 (13)
O1i—K1—N1	93.48 (3)	C2—C1—C4	121.88 (13)
O2ii—K1—N1	98.04 (3)	N1—C1—K1iv	72.68 (8)
O3i—K1—N1	150.55 (3)	C2—C1—K1iv	71.72 (8)
O1—K1—N1	22.86 (3)	C4—C1—K1iv	129.38 (10)
O2—K1—N1	23.19 (3)	O3—C2—O4	121.61 (14)
O3iii—K1—N1	78.35 (3)	O3—C2—C1	129.29 (14)
O1iii—K1—N1	125.49 (3)	O4—C2—C1	109.10 (12)
C5ii—K1—N1	80.70 (4)	O3—C2—K1iv	61.45 (8)
O1i—K1—C2iii	97.99 (4)	O4—C2—K1iv	135.44 (9)
O2ii—K1—C2iii	98.10 (4)	C1—C2—K1iv	83.41 (9)
O3i—K1—C2iii	118.31 (4)	O4—C3—H3A	109.5
O1—K1—C2iii	83.79 (3)	O4—C3—H3B	109.5
O2—K1—C2iii	71.83 (3)	H3A—C3—H3B	109.5
O3iii—K1—C2iii	21.75 (3)	O4—C3—H3C	109.5
O1iii—K1—C2iii	53.27 (3)	H3A—C3—H3C	109.5
C5ii—K1—C2iii	150.79 (4)	H3B—C3—H3C	109.5
N1—K1—C2iii	73.06 (3)	C5—C4—C1	119.13 (14)
O1i—K1—N1iii	120.52 (3)	C5—C4—C6	123.51 (14)
O2ii—K1—N1iii	68.28 (3)	C1—C4—C6	117.33 (13)
O3i—K1—N1iii	96.40 (3)	C5—C4—K1v	66.48 (9)
O1—K1—N1iii	125.11 (3)	C1—C4—K1v	99.55 (9)
O2—K1—N1iii	94.52 (3)	C6—C4—K1v	105.93 (10)
O3iii—K1—N1iii	56.00 (3)	C4—C5—K1v	90.11 (10)
O1iii—K1—N1iii	22.80 (3)	C4—C5—H5A	120.0
C5ii—K1—N1iii	140.88 (4)	K1v—C5—H5A	88.2
N1—K1—N1iii	107.96 (4)	C4—C5—H5B	120.0
C2iii—K1—N1iii	43.50 (4)	K1v—C5—H5B	91.7
O1i—K1—C4ii	115.12 (4)	H5A—C5—H5B	120.0
O2ii—K1—C4ii	51.13 (3)	C4—C6—H6A	109.5
O3i—K1—C4ii	89.44 (4)	C4—C6—H6B	109.5
O1—K1—C4ii	95.85 (4)	H6A—C6—H6B	109.5
O2—K1—C4ii	83.16 (3)	C4—C6—H6C	109.5
O3iii—K1—C4ii	166.33 (3)	H6A—C6—H6C	109.5
O1iii—K1—C4ii	124.33 (4)	H6B—C6—H6C	109.5
C5ii—K1—C4ii	23.41 (4)
O1i—K1—O1—N1	160.77 (10)	O1iii—K1—N1—O1	−125.49 (9)
O2ii—K1—O1—N1	−35.71 (9)	C5ii—K1—N1—O1	77.40 (8)
O3i—K1—O1—N1	−178.51 (7)	C2iii—K1—N1—O1	−115.56 (8)
O2—K1—O1—N1	−10.30 (7)	N1iii—K1—N1—O1	−141.94 (7)
O3iii—K1—O1—N1	81.97 (8)	C4ii—K1—N1—O1	97.17 (8)
O1iii—K1—O1—N1	72.42 (10)	O1i—K1—N1—O2	−179.41 (8)
C5ii—K1—O1—N1	−98.01 (8)	O2ii—K1—N1—O2	−12.78 (9)
C2iii—K1—O1—N1	60.23 (8)	O3i—K1—N1—O2	−158.75 (8)
N1iii—K1—O1—N1	45.79 (8)	O1—K1—N1—O2	−161.15 (13)
C4ii—K1—O1—N1	−84.68 (8)	O3iii—K1—N1—O2	105.08 (8)
O1i—K1—O1—K1i	0.0	O1iii—K1—N1—O2	73.36 (8)
O2ii—K1—O1—K1i	163.52 (4)	C5ii—K1—N1—O2	−83.74 (8)
O3i—K1—O1—K1i	20.72 (6)	C2iii—K1—N1—O2	83.29 (8)
O2—K1—O1—K1i	−171.07 (6)	N1iii—K1—N1—O2	56.91 (9)
O3iii—K1—O1—K1i	−78.80 (4)	C4ii—K1—N1—O2	−63.97 (8)
O1iii—K1—O1—K1i	−88.35 (6)	O1i—K1—N1—C1	81.4 (3)
C5ii—K1—O1—K1i	101.21 (5)	O2ii—K1—N1—C1	−112.0 (3)
N1—K1—O1—K1i	−160.77 (10)	O3i—K1—N1—C1	102.0 (3)
C2iii—K1—O1—K1i	−100.54 (4)	O1—K1—N1—C1	99.6 (4)
N1iii—K1—O1—K1i	−114.98 (4)	O2—K1—N1—C1	−99.2 (3)
C4ii—K1—O1—K1i	114.55 (4)	O3iii—K1—N1—C1	5.9 (3)
O1i—K1—O1—K1iv	−91.64 (6)	O1iii—K1—N1—C1	−25.9 (3)
O2ii—K1—O1—K1iv	71.88 (6)	C5ii—K1—N1—C1	177.0 (3)
O3i—K1—O1—K1iv	−70.93 (7)	C2iii—K1—N1—C1	−15.9 (3)
O2—K1—O1—K1iv	97.29 (7)	N1iii—K1—N1—C1	−42.3 (4)
O3iii—K1—O1—K1iv	−170.45 (6)	C4ii—K1—N1—C1	−163.2 (3)
O1iii—K1—O1—K1iv	180.0	O1i—K1—N1—K1iv	−56.32 (4)
C5ii—K1—O1—K1iv	9.57 (6)	O2ii—K1—N1—K1iv	110.31 (4)
N1—K1—O1—K1iv	107.58 (10)	O3i—K1—N1—K1iv	−35.66 (9)
C2iii—K1—O1—K1iv	167.82 (6)	O1—K1—N1—K1iv	−38.06 (7)
N1iii—K1—O1—K1iv	153.38 (4)	O2—K1—N1—K1iv	123.09 (9)
C4ii—K1—O1—K1iv	22.91 (6)	O3iii—K1—N1—K1iv	−131.83 (4)
O1i—K1—O2—N1	0.66 (9)	O1iii—K1—N1—K1iv	−163.55 (3)
O2ii—K1—O2—N1	166.92 (9)	C5ii—K1—N1—K1iv	39.34 (4)
O3i—K1—O2—N1	66.31 (19)	C2iii—K1—N1—K1iv	−153.62 (4)
O1—K1—O2—N1	10.16 (7)	N1iii—K1—N1—K1iv	180.0
O3iii—K1—O2—N1	−71.65 (8)	C4ii—K1—N1—K1iv	59.12 (4)
O1iii—K1—O2—N1	−119.59 (8)	O1—N1—C1—C2	5.1 (2)
C5ii—K1—O2—N1	92.06 (8)	O2—N1—C1—C2	−174.70 (13)
C2iii—K1—O2—N1	−89.27 (8)	K1—N1—C1—C2	−84.2 (4)
N1iii—K1—O2—N1	−126.92 (9)	K1iv—N1—C1—C2	55.71 (13)
C4ii—K1—O2—N1	115.38 (8)	O1—N1—C1—C4	−176.54 (12)
O1i—K1—O2—K1v	−135.53 (5)	O2—N1—C1—C4	3.7 (2)
O2ii—K1—O2—K1v	30.73 (5)	K1—N1—C1—C4	94.1 (3)
O3i—K1—O2—K1v	−69.88 (17)	K1iv—N1—C1—C4	−125.94 (12)
O1—K1—O2—K1v	−126.03 (7)	O1—N1—C1—K1iv	−50.60 (12)
O3iii—K1—O2—K1v	152.16 (5)	O2—N1—C1—K1iv	129.60 (12)
O1iii—K1—O2—K1v	104.22 (5)	K1—N1—C1—K1iv	−139.9 (3)
C5ii—K1—O2—K1v	−44.14 (6)	K1i—O3—C2—O4	−153.88 (10)
N1—K1—O2—K1v	−136.19 (11)	K1iv—O3—C2—O4	128.14 (13)
C2iii—K1—O2—K1v	134.54 (6)	K1i—O3—C2—C1	25.9 (3)
N1iii—K1—O2—K1v	96.89 (5)	K1iv—O3—C2—C1	−52.12 (17)
C4ii—K1—O2—K1v	−20.81 (5)	K1i—O3—C2—K1iv	77.98 (12)
K1i—O1—N1—O2	163.96 (11)	C3—O4—C2—O3	−2.9 (2)
K1—O1—N1—O2	18.87 (12)	C3—O4—C2—C1	177.36 (12)
K1iv—O1—N1—O2	−119.37 (11)	C3—O4—C2—K1iv	77.08 (17)
K1i—O1—N1—C1	−15.8 (2)	N1—C1—C2—O3	−11.9 (2)
K1—O1—N1—C1	−160.93 (12)	C4—C1—C2—O3	169.81 (15)
K1iv—O1—N1—C1	60.82 (14)	K1iv—C1—C2—O3	44.26 (15)
K1i—O1—N1—K1	145.09 (16)	N1—C1—C2—O4	167.86 (13)
K1iv—O1—N1—K1	−138.24 (6)	C4—C1—C2—O4	−10.4 (2)
K1i—O1—N1—K1iv	−76.67 (13)	K1iv—C1—C2—O4	−135.97 (11)
K1—O1—N1—K1iv	138.24 (6)	N1—C1—C2—K1iv	−56.16 (13)
K1v—O2—N1—O1	123.95 (10)	C4—C1—C2—K1iv	125.55 (13)
K1—O2—N1—O1	−18.09 (12)	N1—C1—C4—C5	101.20 (18)
K1v—O2—N1—C1	−56.24 (15)	C2—C1—C4—C5	−80.5 (2)
K1—O2—N1—C1	161.72 (11)	K1iv—C1—C4—C5	11.4 (2)
K1v—O2—N1—K1	142.04 (8)	N1—C1—C4—C6	−80.71 (18)
K1v—O2—N1—K1iv	49.79 (12)	C2—C1—C4—C6	97.62 (18)
K1—O2—N1—K1iv	−92.25 (8)	K1iv—C1—C4—C6	−170.51 (10)
O1i—K1—N1—O1	−18.26 (10)	N1—C1—C4—K1v	32.88 (14)
O2ii—K1—N1—O1	148.37 (8)	C2—C1—C4—K1v	−148.79 (12)
O3i—K1—N1—O1	2.40 (12)	K1iv—C1—C4—K1v	−56.92 (11)
O2—K1—N1—O1	161.15 (13)	C1—C4—C5—K1v	−87.97 (13)
O3iii—K1—N1—O1	−93.78 (8)	C6—C4—C5—K1v	94.06 (15)

Table 1

Selected bond lengths (Å)

K1—O1i	2.7036 (10)
K1—O2ii	2.7539 (11)
K1—O3i	2.7988 (11)
K1—O1	2.7994 (11)
K1—O2	2.8896 (10)
K1—O3iii	2.8970 (12)
K1—O1iii	2.9080 (11)

Symmetry codes: (i) ; (ii) ; (iii) .