(Z)-tert-Butyl 2-(4-amino-9H-fluoren-9-yl-idene)acetate.

The title compound, C(19)H(19)NO(2), obtained as an almost equimolar mixture (as shown by (1)H NMR) with the E isomer through a Wittig reaction between 4-amino-9H-fluoren-9-one and the stabilized ylide Ph(3)P=CHCO(2)C(CH(3))(3), was obtained pure in the Z configuration following crystallization from toluene. The mol-ecule shows a planar arrangement of the ring system and the new double bond, whereas the carbonyl O atom forms a 45.1 (3)° dihedral angle with it. The mol-ecules are linked by N-H⋯O hydrogen bonds, forming cyclic structures with R(4) (4)(24) graph-set motifs. These motifs are connected to each other, giving rise to a sheet structure parallel to the ab plane. The linkage within the sheets is further enhanced by π-π stacking inter-actions between the fluorene units [centroid-centroid distance = 3.583 (2) Å].

Related literature

For general background on retinoids, see: Meyer et al. (1978 ▶); Sporn et al. (1994 ▶). For hydrogen-bond motifs, see: Bernstein et al. (1995 ▶). For related literature, see: Magoulas & Papaioannou (2003 ▶).

Experimental

Crystal data

C19H19NO2

M = 293.35

Orthorhombic,

a = 9.0820 (12) Å

b = 13.7330 (17) Å

c = 24.568 (3) Å

V = 3064.2 (7) Å3

Z = 8

Mo Kα radiation

μ = 0.08 mm−1

T = 100 (2) K

0.32 × 0.26 × 0.16 mm

Data collection

Oxford Diffraction Xcalibur-3 with Sapphire CCD diffractometer

Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2008 ▶) T min = 0.956, T max = 0.989

18331 measured reflections

2671 independent reflections

1671 reflections with I > 2σ(I)

R int = 0.119

Refinement

R[F 2 > 2σ(F 2)] = 0.063

wR(F 2) = 0.143

S = 1.01

2671 reflections

211 parameters

H atoms treated by a mixture of independent and constrained refinement

Δρmax = 0.30 e Å−3

Δρmin = −0.22 e Å−3

Data collection: CrysAlis CCD (Oxford Diffraction, 2008 ▶); cell refinement: CrysAlis RED (Oxford Diffraction, 2008 ▶); data reduction: CrysAlis RED; program(s) used to solve structure: SIR92 (Altomare et al., 1994 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: PLATON (Spek, 2003 ▶), ORTEP-3 (Farrugia, 1997 ▶) and DIAMOND (Brandenburg, 2008 ▶); software used to prepare material for publication: WinGX (Farrugia, 1999 ▶) and publCIF (Westrip, 2008 ▶).

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536808029735/dn2370sup1.cif

Structure factors: contains datablocks I. DOI: 10.1107/S1600536808029735/dn2370Isup2.hkl

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

C19H19NO2	F(000) = 1248
Mr = 293.35	Dx = 1.272 Mg m−3
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 3945 reflections
a = 9.0820 (12) Å	θ = 3.1–30.2°
b = 13.7330 (17) Å	µ = 0.08 mm−1
c = 24.568 (3) Å	T = 100 K
V = 3064.2 (7) Å3	Prism, light yellow
Z = 8	0.32 × 0.26 × 0.16 mm

Oxford Diffraction Xcalibur-3 with Sapphire CCD diffractometer	2671 independent reflections
Radiation source: Enhance (Mo) X-ray source	1671 reflections with I > 2σ(I)
graphite	Rint = 0.119
Detector resolution: 16.0288 pixels mm-1	θmax = 25.0°, θmin = 3.2°
ω and φ scans	h = −8→10
Absorption correction: multi-scan (CrysAlis RED; Oxford Diffraction, 2008)	k = −16→14
Tmin = 0.956, Tmax = 0.989	l = −27→29
18331 measured reflections

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)] = 0.063	Hydrogen site location: difference Fourier map
wR(F2) = 0.143	H atoms treated by a mixture of independent and constrained refinement
S = 1.01	w = 1/[σ2(Fo2) + (0.069P)2] where P = (Fo2 + 2Fc2)/3
2671 reflections	(Δ/σ)max < 0.001
211 parameters	Δρmax = 0.30 e Å−3
0 restraints	Δρmin = −0.22 e Å−3

Experimental. IR (KBr, n, cm-1): 3404 and 3338 (w), 1700 (s), 1628 (m); 1H NMR (400 MHz, CDCl3): d 8.329 (d, J = 7.6 Hz, 1H, H-8), 7.623 (d, J = 7.6 Hz, 1H, H-5), 7.528 (d, J= 7.6 Hz, 1H, H-1), 7.319 (t, J = 6.8 Hz, 1H, H-7), 7.152 (t, J= 6.8 Hz, 1H, H-6), 7.089 (t, J = 8 Hz, 1H, H-2), 6.707 (d, J= 7.6 Hz, 1H, H-3), 6.628 (s, 1H, H-10), 3.959 (s, 2H, NH2),1.541 (s, 9H, H-13) p.p.m.; EI—MS m/z: 293 (M+, 9), 237 (100), 220 (11), 193 (13), 180 (17), 165 (12).

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.

	x	y	z	Uiso*/Ueq
C1'	0.1196 (3)	0.06224 (19)	0.71979 (11)	0.0225 (7)
C1	0.0627 (3)	0.11302 (19)	0.67557 (12)	0.0268 (7)
H1	0.0906	0.0977	0.6402	0.032*
C2	−0.0373 (3)	0.18742 (19)	0.68596 (12)	0.0301 (7)
H2	−0.0751	0.2232	0.6570	0.036*
C3	−0.0816 (3)	0.20922 (19)	0.73829 (12)	0.0275 (7)
H3	−0.1496	0.2589	0.7437	0.033*
C4	−0.0270 (3)	0.15855 (19)	0.78340 (12)	0.0236 (7)
C4'	0.0775 (3)	0.08588 (18)	0.77339 (11)	0.0225 (7)
C5'	0.1565 (3)	0.02216 (19)	0.81212 (12)	0.0225 (7)
C5	0.1598 (3)	0.0176 (2)	0.86812 (12)	0.0271 (7)
H5	0.1017	0.0592	0.8888	0.033*
C6	0.2509 (3)	−0.0500 (2)	0.89319 (12)	0.0315 (8)
H6	0.2537	−0.0534	0.9310	0.038*
C7	0.3378 (3)	−0.1125 (2)	0.86264 (12)	0.0294 (7)
H7	0.3974	−0.1579	0.8801	0.035*
C8	0.3365 (3)	−0.1077 (2)	0.80637 (11)	0.0248 (7)
H8	0.3956	−0.1492	0.7859	0.030*
C8'	0.2461 (3)	−0.04057 (18)	0.78088 (11)	0.0216 (7)
C9	0.2258 (3)	−0.02063 (19)	0.72239 (12)	0.0224 (7)
C10	0.2879 (3)	−0.0755 (2)	0.68355 (12)	0.0241 (7)
H10	0.350 (3)	−0.129 (2)	0.6933 (11)	0.029*
C11	0.2785 (3)	−0.0635 (2)	0.62405 (12)	0.0258 (7)
C12	0.2695 (3)	−0.1621 (2)	0.54059 (11)	0.0268 (7)
C13	0.2656 (4)	−0.2720 (2)	0.53364 (13)	0.0450 (9)
H13A	0.3497	−0.3003	0.5512	0.067*
H13B	0.2675	−0.2878	0.4956	0.067*
H13C	0.1772	−0.2974	0.5497	0.067*
C14	0.4087 (4)	−0.1212 (3)	0.51722 (13)	0.0445 (9)
H14A	0.4062	−0.0514	0.5194	0.067*
H14B	0.4175	−0.1406	0.4798	0.067*
H14C	0.4915	−0.1453	0.5374	0.067*
C15	0.1325 (4)	−0.1164 (2)	0.51698 (13)	0.0421 (9)
H15A	0.0472	−0.1425	0.5349	0.063*
H15B	0.1272	−0.1304	0.4787	0.063*
H15C	0.1358	−0.0472	0.5223	0.063*
N	−0.0702 (3)	0.18283 (18)	0.83630 (11)	0.0298 (6)
H1N	−0.147 (4)	0.218 (2)	0.8360 (13)	0.045*
H2N	−0.095 (3)	0.132 (2)	0.8587 (13)	0.045*
O1	0.2699 (2)	−0.15191 (12)	0.60048 (7)	0.0262 (5)
O2	0.2815 (3)	0.01219 (14)	0.59924 (8)	0.0384 (6)

	U11	U22	U33	U12	U13	U23
C1'	0.0268 (16)	0.0110 (14)	0.0297 (17)	−0.0066 (12)	−0.0013 (13)	−0.0008 (12)
C1	0.0332 (17)	0.0165 (15)	0.0306 (17)	−0.0016 (13)	−0.0030 (14)	0.0037 (13)
C2	0.0370 (19)	0.0179 (15)	0.0353 (18)	−0.0032 (14)	−0.0047 (15)	0.0060 (14)
C3	0.0291 (18)	0.0108 (15)	0.043 (2)	0.0003 (13)	−0.0027 (15)	−0.0014 (13)
C4	0.0264 (16)	0.0130 (14)	0.0314 (18)	−0.0047 (12)	0.0012 (14)	−0.0025 (12)
C4'	0.0288 (16)	0.0111 (14)	0.0277 (17)	−0.0044 (12)	−0.0031 (13)	0.0004 (12)
C5'	0.0263 (16)	0.0124 (14)	0.0289 (17)	−0.0047 (12)	−0.0032 (14)	−0.0029 (12)
C5	0.0349 (18)	0.0194 (15)	0.0270 (17)	−0.0007 (13)	0.0022 (14)	−0.0055 (13)
C6	0.0423 (19)	0.0264 (17)	0.0259 (17)	−0.0013 (15)	−0.0006 (15)	−0.0039 (13)
C7	0.0369 (18)	0.0204 (16)	0.0310 (18)	0.0022 (14)	−0.0043 (15)	−0.0008 (14)
C8	0.0316 (17)	0.0146 (14)	0.0281 (17)	−0.0009 (13)	−0.0018 (14)	−0.0051 (13)
C8'	0.0296 (16)	0.0109 (13)	0.0243 (16)	−0.0051 (12)	−0.0001 (14)	−0.0038 (12)
C9	0.0230 (16)	0.0126 (14)	0.0317 (17)	−0.0043 (12)	−0.0033 (14)	−0.0004 (12)
C10	0.0329 (18)	0.0107 (14)	0.0287 (17)	−0.0011 (12)	−0.0011 (14)	−0.0008 (13)
C11	0.0332 (18)	0.0153 (15)	0.0288 (16)	−0.0029 (13)	0.0013 (14)	−0.0008 (13)
C12	0.0359 (18)	0.0220 (16)	0.0225 (16)	−0.0015 (14)	0.0017 (14)	−0.0009 (12)
C13	0.083 (3)	0.0263 (18)	0.0259 (18)	−0.0044 (18)	0.0041 (18)	−0.0059 (14)
C14	0.052 (2)	0.053 (2)	0.0285 (18)	−0.0116 (18)	0.0043 (17)	0.0036 (16)
C15	0.049 (2)	0.046 (2)	0.0303 (18)	0.0002 (17)	−0.0025 (17)	−0.0051 (16)
N	0.0346 (16)	0.0172 (14)	0.0374 (16)	0.0019 (12)	0.0056 (13)	−0.0018 (12)
O1	0.0446 (13)	0.0125 (10)	0.0214 (11)	−0.0021 (9)	0.0032 (10)	−0.0001 (8)
O2	0.0723 (17)	0.0127 (10)	0.0303 (12)	−0.0024 (10)	−0.0025 (11)	0.0043 (9)

C1'—C1	1.391 (4)	C8'—C9	1.475 (4)
C1'—C4'	1.409 (4)	C9—C10	1.340 (4)
C1'—C9	1.493 (4)	C10—C11	1.474 (4)
C1—C2	1.391 (4)	C10—H10	0.96 (3)
C1—H1	0.9300	C11—O2	1.205 (3)
C2—C3	1.380 (4)	C11—O1	1.347 (3)
C2—H2	0.9300	C12—O1	1.478 (3)
C3—C4	1.399 (4)	C12—C14	1.498 (4)
C3—H3	0.9300	C12—C15	1.510 (4)
C4—N	1.398 (4)	C12—C13	1.519 (4)
C4—C4'	1.400 (4)	C13—H13A	0.9600
C4'—C5'	1.478 (4)	C13—H13B	0.9600
C5'—C5	1.377 (4)	C13—H13C	0.9600
C5'—C8'	1.412 (4)	C14—H14A	0.9600
C5—C6	1.387 (4)	C14—H14B	0.9600
C5—H5	0.9300	C14—H14C	0.9600
C6—C7	1.387 (4)	C15—H15A	0.9600
C6—H6	0.9300	C15—H15B	0.9600
C7—C8	1.384 (4)	C15—H15C	0.9600
C7—H7	0.9300	N—H1N	0.85 (3)
C8—C8'	1.384 (4)	N—H2N	0.92 (3)
C8—H8	0.9300
C1—C1'—C4'	120.9 (3)	C10—C9—C1'	132.1 (3)
C1—C1'—C9	131.0 (3)	C8'—C9—C1'	105.3 (2)
C4'—C1'—C9	108.1 (2)	C9—C10—C11	128.3 (3)
C1'—C1—C2	117.9 (3)	C9—C10—H10	120.2 (16)
C1'—C1—H1	121.1	C11—C10—H10	111.5 (16)
C2—C1—H1	121.1	O2—C11—O1	124.1 (3)
C3—C2—C1	121.4 (3)	O2—C11—C10	126.6 (3)
C3—C2—H2	119.3	O1—C11—C10	109.2 (2)
C1—C2—H2	119.3	O1—C12—C14	110.1 (2)
C2—C3—C4	121.8 (3)	O1—C12—C15	110.2 (2)
C2—C3—H3	119.1	C14—C12—C15	113.1 (3)
C4—C3—H3	119.1	O1—C12—C13	101.9 (2)
N—C4—C3	121.2 (3)	C14—C12—C13	110.5 (3)
N—C4—C4'	121.6 (3)	C15—C12—C13	110.6 (3)
C3—C4—C4'	117.1 (3)	C12—C13—H13A	109.5
C4—C4'—C1'	120.8 (3)	C12—C13—H13B	109.5
C4—C4'—C5'	129.7 (3)	H13A—C13—H13B	109.5
C1'—C4'—C5'	109.5 (2)	C12—C13—H13C	109.5
C5—C5'—C8'	120.2 (3)	H13A—C13—H13C	109.5
C5—C5'—C4'	132.9 (3)	H13B—C13—H13C	109.5
C8'—C5'—C4'	106.9 (2)	C12—C14—H14A	109.5
C5'—C5—C6	119.1 (3)	C12—C14—H14B	109.5
C5'—C5—H5	120.4	H14A—C14—H14B	109.5
C6—C5—H5	120.4	C12—C14—H14C	109.5
C5—C6—C7	120.9 (3)	H14A—C14—H14C	109.5
C5—C6—H6	119.6	H14B—C14—H14C	109.5
C7—C6—H6	119.6	C12—C15—H15A	109.5
C8—C7—C6	120.4 (3)	C12—C15—H15B	109.5
C8—C7—H7	119.8	H15A—C15—H15B	109.5
C6—C7—H7	119.8	C12—C15—H15C	109.5
C8'—C8—C7	119.3 (3)	H15A—C15—H15C	109.5
C8'—C8—H8	120.4	H15B—C15—H15C	109.5
C7—C8—H8	120.4	C4—N—H1N	111 (2)
C8—C8'—C5'	120.1 (3)	C4—N—H2N	116 (2)
C8—C8'—C9	129.7 (2)	H1N—N—H2N	104 (3)
C5'—C8'—C9	110.1 (2)	C11—O1—C12	120.9 (2)
C10—C9—C8'	122.4 (3)
C4'—C1'—C1—C2	−0.3 (4)	C7—C8—C8'—C5'	0.0 (4)
C9—C1'—C1—C2	179.3 (3)	C7—C8—C8'—C9	179.4 (3)
C1'—C1—C2—C3	−1.4 (4)	C5—C5'—C8'—C8	0.8 (4)
C1—C2—C3—C4	0.8 (4)	C4'—C5'—C8'—C8	178.5 (2)
C2—C3—C4—N	178.5 (3)	C5—C5'—C8'—C9	−178.8 (2)
C2—C3—C4—C4'	1.4 (4)	C4'—C5'—C8'—C9	−1.0 (3)
N—C4—C4'—C1'	179.9 (2)	C8—C8'—C9—C10	6.5 (5)
C3—C4—C4'—C1'	−3.1 (4)	C5'—C8'—C9—C10	−174.0 (3)
N—C4—C4'—C5'	1.6 (4)	C8—C8'—C9—C1'	−177.6 (3)
C3—C4—C4'—C5'	178.7 (3)	C5'—C8'—C9—C1'	1.9 (3)
C1—C1'—C4'—C4	2.6 (4)	C1—C1'—C9—C10	−6.4 (5)
C9—C1'—C4'—C4	−177.1 (2)	C4'—C1'—C9—C10	173.2 (3)
C1—C1'—C4'—C5'	−178.8 (2)	C1—C1'—C9—C8'	178.3 (3)
C9—C1'—C4'—C5'	1.5 (3)	C4'—C1'—C9—C8'	−2.0 (3)
C4—C4'—C5'—C5	−4.5 (5)	C8'—C9—C10—C11	−179.2 (3)
C1'—C4'—C5'—C5	177.1 (3)	C1'—C9—C10—C11	6.2 (5)
C4—C4'—C5'—C8'	178.1 (3)	C9—C10—C11—O2	39.7 (5)
C1'—C4'—C5'—C8'	−0.3 (3)	C9—C10—C11—O1	−142.0 (3)
C8'—C5'—C5—C6	−0.7 (4)	O2—C11—O1—C12	2.5 (4)
C4'—C5'—C5—C6	−177.8 (3)	C10—C11—O1—C12	−175.8 (2)
C5'—C5—C6—C7	−0.1 (4)	C14—C12—O1—C11	60.3 (3)
C5—C6—C7—C8	0.8 (5)	C15—C12—O1—C11	−65.1 (3)
C6—C7—C8—C8'	−0.7 (4)	C13—C12—O1—C11	177.6 (2)

D—H···A	D—H	H···A	D···A	D—H···A
N—H1N···O1i	0.85 (3)	2.62 (3)	3.295 (3)	137 (3)
N—H2N···O2ii	0.92 (3)	2.24 (3)	3.133 (3)	163 (3)

Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
N—H1N⋯O1i	0.85 (3)	2.62 (3)	3.295 (3)	137 (3)
N—H2N⋯O2ii	0.92 (3)	2.24 (3)	3.133 (3)	163 (3)

Symmetry codes: (i) ; (ii) .