2-Amino-4-(4-chlorophenyl)-7,7-dimethyl-5-oxo-5,6,7,8-tetrahydro-4H-chromene-3-carbonitrile

The supramolecular structure of the title compound, C₁₈H₁₇ClN₂O₂, is determined by the intersection of two chains formed by N—H...O and N—H...N hydrogen bonds, forming a two-dimensional sheet.

S1. Comment

The structure of 2-amino-7,7-dimethyl-5-oxo-4-phenyl-5,6,7,8-tetrahydro-4H- chromene-3-carbonitrile, (II), has been reported by Tu et al. (2001). Here, we report the structure of the title 4-chlorophenyl analogue, (I). \sch

In (II), the N—H···N hydrogen bond links the molecules into dimers, which are then linked to form a three-dimensional network via the N—H···O(oxo) hydrogen bond, but the supramolecular structure of (I) is completely different. In (I) (Fig. 1, where the S enantiomer has been arbitrarily chosen as the asymmetric unit), the basic supramolecular motifs are two chains. An N2—H2B···N31 hydrogen bond forms a C(6) chain (Bernstein et al., 1995), which runs parallel to [001], linking molecules related by the c-glide plane at y = 1/4. These chains are then linked together by a C(8) chain, formed by the N2—H2A···O5 hydrogen bond, which runs parallel to [201]. The combination of these two chains generates a sheet of R₄⁴(24) rings (Fig. 2). This sheet lies in the range 0 < y < 1/2, and another antiparallel sheet lies in the range 1/2 < y < 1.0.

Atom N31 in the molecule at (x, y, z) acts as an acceptor for amino atom N2, via atom H2B, in the molecule at (x, 1/2 − y, z − 1/2). Atom O5 in the molecule at (x, y, z) acts as an acceptor for amino atom N2, via atom H2A, in the molecule at (x − 1, 1/2 − y, z − 1/2). Atom N31 in the molecule at (x − 1, 1/2 − y, z − 1/2) acts as an acceptor for amino atom N2, via atom H2B, in the molecule at (x − 1, y, z − 1). Finally, atom N2 in the molecule at (x − 1, y, z − 1) acts as a donor, via atom H2A, to atom O5 in the molecule at (x, 1/2 − y, z − 1/2), thus completing the ring.

There is also a contact between atom Cl4 and atom O1 at (2 − x, −y, 1 − z), with a Cl···O distance of 3.192 (2) Å, which is just less than the sum of the van der Waals radii of Cl and O (3.20 Å; reference?). The C44—Cl4···O1 angle is 159.34 (8)°. A search of the Cambridge Structure Database (CSD, Version?; Allen, 2002), gives 68 hits for Cl···O(ring) contacts. Of these contacts, only three are less than the sum of the van der Waals radii, and all the others range between 3.294 and 4.247 Å. Thus, contacts less than 3.20 Å are rare. In 3,4,5,6,7-pentachloro-8-oxatricyclo(4.3.0.0^3,7)non-4-ene (refcode JEMXUU; Shnulin et al., 1989), the Cl···O distance is 3.049 Å and the angle at Cl is 153.8°. In N-(2,6-dichlorophenyl)-1,2-epimino-3,4-epoxycyclopentane (refcode KOJJUO; Rousselle et al., 1991), the Cl···O distance is 3.114 Å and the angle at Cl is 165.7°. In N-(2,2-dichlorovinyl)-1,2-epimino-4,5-epoxy-cyclopentane (refcode XZCVIN10; Van Meerssche et al., 1977), the Cl···O distance is 2.961 Å and the angle at Cl is 179.0°. It is also worth noting that in (I) and the compounds cited above, the angles at Cl are all greater than 153°, whereas the angles at Cl for the rest of the compounds in the search range between 60 and 170°, randomly.

There are no unusual bond lengths and angles in (I), and they are in agreement with those found in (II).

S2. Experimental

A solution of p-chlorobenzylidenmalonodinitrile (1 mmol) and 5,5-dimethylcyclohexane-1,3-dione (1 mmol) in absolute ethanol (10 ml) was heated under reflux for 6 h using the method described by Tu et al. (2001). The resulting precipitate was isolated by filtration, washed with ethanol, dried and recrystallized from ethanol (yield 80%, m.p. 491 K). Analysis, required for C₁₈H₁₇ClN₂O₂: C 65.8, H 5.2, N 8.5%; found: C 65.7, H 5.2, N 8.6%.

S3. Refinement

Space group P2₁/c was deduced from the systematic absences. H atoms were treated as riding atoms, with C—H distances in the range 0.95–1.00 Å and N—H distances of 0.92 Å. These latter atoms were DFIXed to this value based on positions found on a difference map, and then AFIXed in the final cycles (SHELXL97; Sheldrick, 1997). It is worth noting that the amino group is not planar in (I), and therefore the use of AFIX 93 would give a false position for the amino H atoms.

Computing details

Data collection: KappaCCD Server Software (Nonius, 1997); cell refinement: DENZO-SMN (Otwinowski & Minor, 1997); data reduction: DENZO-SMN; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2002); software used to prepare material for publication: SHELXL97 and PRPKAPPA (Ferguson, 1999).

Figures

	Fig. 1. A view of (I) with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level and H atoms are shown as small spheres of arbitrary radii.
	Fig. 2. The R4^4(24) ring in (I), formed by the intersection of the C(6) and C(8) chains. The atoms labelled with an asterisk (*), hash (#) or ampersand (add) are at the symmetry positions (x − 1, 1/2 − y, z − 1/2), (x − 1, y, z − 1) and (x, 1/2 − y, z − 1/2), respectively.

2-Amino-4-(4-chlorophenyl)-7,7-dimethyl-5-oxo-5,6,7,8-tetrahydro- 4H-chromene-3-carbonitrile

Crystal data

C18H17ClN2O2	F(000) = 688
Mr = 328.79	Dx = 1.410 Mg m^−3
Monoclinic, P21/c	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ybc	Cell parameters from 3487 reflections
a = 9.3867 (3) Å	θ = 3.2–27.5°
b = 16.5328 (5) Å	µ = 0.26 mm^−1
c = 11.3189 (3) Å	T = 120 K
β = 118.118 (2)°	Plate, colourless
V = 1549.25 (8) Å^3	0.20 × 0.08 × 0.08 mm
Z = 4

Data collection

Nonius KappaCCD area-detector diffractometer	3487 independent reflections
Radiation source: fine-focus sealed X-ray tube	2262 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.066
ϕ scans, and ω scans with κ offsets	θmax = 27.5°, θmin = 3.2°
Absorption correction: multi-scan (DENZO-SMN; Otwinowski & Minor, 1997)	h = −12→12
Tmin = 0.950, Tmax = 0.980	k = −18→21
12189 measured 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)] = 0.047	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.130	H-atom parameters constrained
S = 1.02	w = 1/[σ^2(Fo^2) + (0.066P)^2] where P = (Fo^2 + 2Fc^2)/3
3487 reflections	(Δ/σ)max < 0.001
210 parameters	Δρmax = 0.29 e Å^−3
0 restraints	Δρmin = −0.36 e Å^−3

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

	x	y	z	Uiso*/Ueq
O1	1.05977 (16)	0.12526 (9)	0.93616 (13)	0.0193 (3)
C2	1.1703 (2)	0.17464 (13)	0.9250 (2)	0.0174 (5)
N2	1.3165 (2)	0.16414 (11)	1.03040 (17)	0.0215 (4)
C3	1.1266 (2)	0.22400 (13)	0.8172 (2)	0.0186 (5)
C31	1.2434 (3)	0.27795 (14)	0.8168 (2)	0.0201 (5)
N31	1.3360 (2)	0.32177 (13)	0.8123 (2)	0.0285 (5)
C4	0.9599 (2)	0.22099 (13)	0.6978 (2)	0.0183 (5)
C41	0.9520 (3)	0.17200 (13)	0.5793 (2)	0.0186 (5)
C42	1.0909 (3)	0.14356 (14)	0.5798 (2)	0.0231 (5)
C43	1.0853 (3)	0.09895 (14)	0.4734 (2)	0.0244 (5)
C44	0.9372 (3)	0.08326 (13)	0.3652 (2)	0.0231 (5)
C45	0.7960 (3)	0.11042 (14)	0.3611 (2)	0.0258 (5)
C46	0.8045 (3)	0.15503 (14)	0.4686 (2)	0.0236 (5)
C4a	0.8458 (2)	0.18777 (13)	0.7454 (2)	0.0185 (5)
Cl4	0.92791 (7)	0.02733 (4)	0.23137 (6)	0.0322 (2)
O5	0.62502 (18)	0.26384 (9)	0.59283 (15)	0.0243 (4)
C5	0.6759 (3)	0.21176 (13)	0.6813 (2)	0.0195 (5)
C6	0.5667 (3)	0.17401 (14)	0.7303 (2)	0.0237 (5)
C7	0.6197 (3)	0.09028 (14)	0.7915 (2)	0.0204 (5)
C71	0.6025 (3)	0.02970 (15)	0.6829 (2)	0.0274 (5)
C72	0.5166 (3)	0.06171 (15)	0.8553 (2)	0.0262 (5)
C8	0.7960 (3)	0.09647 (14)	0.9007 (2)	0.0218 (5)
C8a	0.8982 (2)	0.13960 (13)	0.8532 (2)	0.0180 (5)
H2A	1.4041	0.1920	1.0355	0.026*
H2B	1.3198	0.1513	1.1107	0.026*
H4	0.9261	0.2777	0.6665	0.022*
H42	1.1927	0.1548	0.6547	0.028*
H43	1.1818	0.0797	0.4754	0.029*
H45	0.6945	0.0989	0.2861	0.031*
H46	0.7077	0.1742	0.4661	0.028*
H6A	0.4562	0.1701	0.6542	0.028*
H6B	0.5620	0.2102	0.7981	0.028*
H71A	0.4889	0.0263	0.6147	0.041*
H71B	0.6399	−0.0237	0.7234	0.041*
H61C	0.6678	0.0478	0.6411	0.041*
H72A	0.5244	0.1010	0.9229	0.039*
H72B	0.5557	0.0090	0.8979	0.039*
H72C	0.4038	0.0569	0.7860	0.039*
H8A	0.8006	0.1255	0.9789	0.026*
H8B	0.8397	0.0414	0.9302	0.026*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0158 (8)	0.0244 (9)	0.0153 (7)	−0.0017 (6)	0.0055 (6)	0.0016 (6)
C2	0.0157 (10)	0.0205 (12)	0.0173 (11)	−0.0036 (9)	0.0089 (9)	−0.0049 (8)
N2	0.0141 (9)	0.0312 (11)	0.0178 (9)	−0.0032 (8)	0.0064 (7)	−0.0003 (7)
C3	0.0186 (11)	0.0198 (12)	0.0187 (11)	−0.0027 (9)	0.0100 (9)	−0.0031 (8)
C31	0.0209 (12)	0.0236 (13)	0.0159 (11)	0.0016 (10)	0.0088 (9)	0.0005 (9)
N31	0.0282 (11)	0.0306 (12)	0.0294 (11)	−0.0036 (9)	0.0158 (9)	−0.0002 (8)
C4	0.0185 (11)	0.0189 (12)	0.0182 (10)	0.0014 (9)	0.0092 (9)	0.0001 (8)
C41	0.0222 (11)	0.0161 (12)	0.0194 (11)	−0.0004 (9)	0.0115 (9)	0.0027 (8)
C42	0.0208 (12)	0.0280 (14)	0.0220 (11)	−0.0005 (10)	0.0112 (9)	−0.0004 (9)
C43	0.0270 (13)	0.0268 (14)	0.0266 (12)	0.0017 (10)	0.0187 (10)	0.0004 (9)
C44	0.0355 (13)	0.0200 (13)	0.0161 (11)	−0.0018 (10)	0.0141 (10)	−0.0001 (9)
C45	0.0247 (13)	0.0296 (14)	0.0197 (12)	−0.0021 (10)	0.0076 (10)	0.0009 (10)
C46	0.0198 (12)	0.0278 (14)	0.0224 (12)	0.0015 (10)	0.0094 (9)	0.0003 (9)
C4a	0.0179 (11)	0.0201 (12)	0.0187 (11)	−0.0004 (9)	0.0096 (9)	−0.0006 (9)
Cl4	0.0465 (4)	0.0318 (4)	0.0217 (3)	0.0006 (3)	0.0190 (3)	−0.0034 (2)
O5	0.0211 (8)	0.0252 (9)	0.0245 (8)	0.0052 (7)	0.0092 (6)	0.0034 (7)
C5	0.0199 (11)	0.0196 (12)	0.0188 (11)	0.0009 (9)	0.0091 (9)	−0.0025 (9)
C6	0.0196 (12)	0.0261 (13)	0.0271 (12)	0.0017 (10)	0.0124 (10)	0.0004 (10)
C7	0.0158 (11)	0.0228 (13)	0.0228 (11)	−0.0006 (9)	0.0092 (9)	−0.0017 (9)
C71	0.0261 (13)	0.0273 (14)	0.0291 (13)	−0.0021 (10)	0.0133 (10)	−0.0052 (10)
C72	0.0212 (12)	0.0276 (14)	0.0336 (13)	−0.0030 (10)	0.0160 (10)	0.0022 (10)
C8	0.0221 (12)	0.0270 (13)	0.0179 (11)	0.0001 (10)	0.0107 (9)	0.0026 (9)
C8a	0.0143 (11)	0.0194 (12)	0.0200 (11)	0.0003 (9)	0.0079 (8)	−0.0034 (9)

Geometric parameters (Å, º)

O1—C2	1.372 (3)	C45—H45	0.95
O1—C8a	1.377 (3)	C46—H46	0.95
C2—N2	1.339 (3)	C4a—C8a	1.341 (3)
C2—C3	1.361 (3)	C4a—C5	1.462 (3)
N2—H2A	0.9199	O5—C5	1.233 (3)
N2—H2B	0.9199	C5—C6	1.512 (3)
C3—C31	1.415 (3)	C6—C7	1.523 (3)
C3—C4	1.511 (3)	C6—H6A	0.99
C31—N31	1.151 (3)	C6—H6B	0.99
C4—C4a	1.511 (3)	C7—C72	1.530 (3)
C4—C41	1.538 (3)	C7—C8	1.533 (3)
C4—H4	1.00	C7—C71	1.534 (3)
C41—C42	1.384 (3)	C71—H71A	0.98
C41—C46	1.390 (3)	C71—H71B	0.98
C42—C43	1.392 (3)	C71—H61C	0.98
C42—H42	0.95	C72—H72A	0.98
C43—C44	1.377 (3)	C72—H72B	0.98
C43—H43	0.95	C72—H72C	0.98
C44—C45	1.379 (3)	C8—C8a	1.484 (3)
C44—Cl4	1.741 (2)	C8—H8A	0.99
C45—C46	1.392 (3)	C8—H8B	0.99
C2—O1—C8a	118.21 (16)	C5—C4a—C4	121.00 (18)
N2—C2—C3	128.7 (2)	O5—C5—C4a	120.49 (19)
N2—C2—O1	110.08 (18)	O5—C5—C6	121.05 (19)
C3—C2—O1	121.18 (18)	C4a—C5—C6	118.40 (19)
C2—N2—H2A	120.1	C5—C6—C7	114.16 (18)
C2—N2—H2B	116.9	C5—C6—H6A	108.7
H2A—N2—H2B	116.2	C7—C6—H6A	108.7
C2—C3—C31	118.29 (19)	C5—C6—H6B	108.7
C2—C3—C4	122.00 (19)	C7—C6—H6B	108.7
C31—C3—C4	119.70 (18)	H6A—C6—H6B	107.6
N31—C31—C3	177.9 (2)	C6—C7—C72	110.57 (18)
C3—C4—C4a	107.58 (17)	C6—C7—C8	107.67 (18)
C3—C4—C41	113.68 (17)	C72—C7—C8	108.81 (18)
C4a—C4—C41	111.60 (17)	C6—C7—C71	109.93 (18)
C3—C4—H4	107.9	C72—C7—C71	109.01 (19)
C4a—C4—H4	107.9	C8—C7—C71	110.85 (18)
C41—C4—H4	107.9	C7—C71—H71A	109.5
C42—C41—C46	118.1 (2)	C7—C71—H71B	109.5
C42—C41—C4	121.15 (19)	H71A—C71—H71B	109.5
C46—C41—C4	120.76 (19)	C7—C71—H61C	109.5
C41—C42—C43	121.7 (2)	H71A—C71—H61C	109.5
C41—C42—H42	119.1	H71B—C71—H61C	109.5
C43—C42—H42	119.1	C7—C72—H72A	109.5
C44—C43—C42	118.7 (2)	C7—C72—H72B	109.5
C44—C43—H43	120.7	H72A—C72—H72B	109.5
C42—C43—H43	120.7	C7—C72—H72C	109.5
C43—C44—C45	121.3 (2)	H72A—C72—H72C	109.5
C43—C44—Cl4	119.30 (18)	H72B—C72—H72C	109.5
C45—C44—Cl4	119.38 (17)	C8a—C8—C7	112.10 (18)
C44—C45—C46	119.0 (2)	C8a—C8—H8A	109.2
C44—C45—H45	120.5	C7—C8—H8A	109.2
C46—C45—H45	120.5	C8a—C8—H8B	109.2
C41—C46—C45	121.2 (2)	C7—C8—H8B	109.2
C41—C46—H46	119.4	H8A—C8—H8B	107.9
C45—C46—H46	119.4	C4a—C8a—O1	122.41 (19)
C8a—C4a—C5	117.33 (18)	C4a—C8a—C8	126.33 (19)
C8a—C4a—C4	121.53 (19)	O1—C8a—C8	111.26 (17)
C8a—O1—C2—N2	166.43 (17)	C3—C4—C4a—C8a	−25.6 (3)
C8a—O1—C2—C3	−14.7 (3)	C41—C4—C4a—C8a	99.8 (2)
N2—C2—C3—C31	−6.3 (3)	C3—C4—C4a—C5	149.91 (19)
O1—C2—C3—C31	175.16 (18)	C41—C4—C4a—C5	−84.7 (2)
N2—C2—C3—C4	172.1 (2)	C8a—C4a—C5—O5	170.8 (2)
O1—C2—C3—C4	−6.5 (3)	C4—C4a—C5—O5	−4.9 (3)
C2—C3—C4—C4a	24.9 (3)	C8a—C4a—C5—C6	−6.5 (3)
C31—C3—C4—C4a	−156.78 (19)	C4—C4a—C5—C6	177.79 (19)
C2—C3—C4—C41	−99.2 (2)	O5—C5—C6—C7	155.5 (2)
C31—C3—C4—C41	79.1 (2)	C4a—C5—C6—C7	−27.2 (3)
C3—C4—C41—C42	−7.9 (3)	C5—C6—C7—C72	172.26 (18)
C4a—C4—C41—C42	−129.8 (2)	C5—C6—C7—C8	53.5 (2)
C3—C4—C41—C46	172.04 (19)	C5—C6—C7—C71	−67.3 (2)
C4a—C4—C41—C46	50.1 (3)	C6—C7—C8—C8a	−48.3 (2)
C46—C41—C42—C43	−0.2 (3)	C72—C7—C8—C8a	−168.19 (19)
C4—C41—C42—C43	179.8 (2)	C71—C7—C8—C8a	71.9 (2)
C41—C42—C43—C44	0.2 (3)	C5—C4a—C8a—O1	−167.68 (18)
C42—C43—C44—C45	−0.3 (3)	C4—C4a—C8a—O1	8.0 (3)
C42—C43—C44—Cl4	−179.82 (17)	C5—C4a—C8a—C8	11.4 (3)
C43—C44—C45—C46	0.4 (3)	C4—C4a—C8a—C8	−173.0 (2)
Cl4—C44—C45—C46	179.93 (17)	C2—O1—C8a—C4a	14.1 (3)
C42—C41—C46—C45	0.3 (3)	C2—O1—C8a—C8	−165.05 (18)
C4—C41—C46—C45	−179.7 (2)	C7—C8—C8a—C4a	17.9 (3)
C44—C45—C46—C41	−0.4 (3)	C7—C8—C8a—O1	−162.99 (17)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2A···O5^i	0.92	2.00	2.894 (3)	165
N2—H2B···N31^ii	0.92	2.26	3.118 (3)	155

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