Conformational axial chirality of phenyl N-[2-(acetyl­amino)biphenyl-4-yl]carbamate

The crystal structure of the title compound, C₂₁H₁₈N₂O₃, reveals an inter­esting case of axial conformational chirality. Due to the symmetry requirements of the space group (P2₁/n), conformational stereoisomers of both P and M helicity are present.

Key indicators

• Single-crystal X-ray study
• T = 293 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.038
• wR factor = 0.110
• Data-to-parameter ratio = 12.7

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT199_ALERT_1_C Check the Reported _cell_measurement_temperature        293 K
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C18    -   C19     ..       5.99 su
PLAT241_ALERT_2_C Check High      Ueq as Compared to Neighbors for         O3
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        C16
PLAT420_ALERT_2_C D-H Without Acceptor       N1     -   H1N    ...          ?
PLAT480_ALERT_4_C Long H...A H-Bond Reported H11    ..  O1      ..       2.65 Ang.

   0 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   6 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
   4 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
   1 ALERT type 4 Improvement, methodology, query or suggestion

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Computing details

Data collection: CAD-4 EXPRESS (Enraf–Nonius, 1994); cell refinement: CAD-4 EXPRESS; data reduction: XCAD4 (Harms & Wocadlo, 1995); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997) and PLATON (Spek, 2003); molecular graphics: ORTEP-3 for Windows (Farrugia, 1997) and Mercury (Macrae et al., 2006); software used to prepare material for publication: WinGX (Farrugia, 1999).

phenyl N-[2-(acetylamino)biphenyl-4-yl]carbamate

Crystal data

C21H18N2O3	F(000) = 728
Mr = 346.37	Dx = 1.275 Mg m^−3
Monoclinic, P21/n	Cu Kα radiation, λ = 1.54184 Å
a = 11.260 (13) Å	Cell parameters from 25 reflections
b = 12.74 (2) Å	θ = 8–17°
c = 12.81 (2) Å	µ = 0.7 mm^−1
β = 100.76 (13)°	T = 293 K
V = 1805 (5) Å^3	Prism, colourless
Z = 4	0.32 × 0.3 × 0.2 mm

Data collection

Enraf–Nonius CAD-4 diffractometer	θmax = 76.5°, θmin = 4.9°
non–profiled ω/2θ scans	h = −14→14
7498 measured reflections	k = 0→16
3756 independent reflections	l = −16→16
2854 reflections with I > 2σ(I)	3 standard reflections every 120 min
Rint = 0.031	intensity decay: −1%

Refinement

Refinement on F^2	H atoms treated by a mixture of independent and constrained refinement
Least-squares matrix: full	w = 1/[σ^2(Fo^2) + (0.0506P)^2 + 0.2871P] where P = (Fo^2 + 2Fc^2)/3
R[F^2 > 2σ(F^2)] = 0.039	(Δ/σ)max < 0.001
wR(F^2) = 0.110	Δρmax = 0.24 e Å^−3
S = 1.02	Δρmin = −0.28 e Å^−3
3756 reflections	Extinction correction: SHELXS97 (Sheldrick, 1997), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
296 parameters	Extinction coefficient: 0.0032 (4)
0 restraints

Special details

Experimental. Spectroscopic analysis: ¹H NMR (DMSO-d₆, δ, p.p.m.): 1.83 (s, CH₃, 3H), 7.16–7.28 (m, BiPhe, 5H, Phe, 3H), 7.36–7.40 (m, BiPhe, 1H, Phe, 2H), 7.50–7.51 (BiPhe, 2H), 9.15 (s, NHCOCH₃, 1H), 10.27 (s, NH, 1H); ¹³C NMR (DMSO-d₆, δ, p.p.m.): 23.02 (CH₃), 118.40, 121.85, 125.39, 125.77, 127.03, 127.34, 129.20, 129.40, 130.05, 133.59, 134.89, 136.07, 137.73, 150.53, 151.70, 168.57; IR (KBr, ν, cm^-1): 3454.26, 3394.47, 3238.24, 3172.67, 3093.59, 3041.52, 2937.37, 2856.37, 2790.79, 2362.63, 2335.62, 2219.90, 1951.82, 1930.60, 1733.88, 1666.37, 1608.51, 1589.23, 1483.15, 1446.51, 1407.93, 1321.14, 1298.00, 1228.57, 1157.20, 1068.49, 1022.20, 1010.63, 916.20, 835.12, 811.97, 796.54, 756.04, 719.40, 663.46, 561.24, 507.24, 466.74, 379.95, 329.80, 287.37.

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.

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

	x	y	z	Uiso*/Ueq	Occ. (<1)
C1	0.31521 (14)	0.46781 (14)	0.88579 (13)	0.0580 (4)
C2	0.19798 (13)	0.42740 (11)	0.82207 (11)	0.0461 (3)
C3	0.08911 (12)	0.38805 (11)	0.64074 (10)	0.0439 (3)
C4	−0.02684 (14)	0.42802 (14)	0.63844 (13)	0.0562 (4)
C5	−0.12322 (15)	0.39400 (16)	0.56271 (15)	0.0683 (5)
C6	−0.10448 (16)	0.32182 (18)	0.48750 (15)	0.0728 (5)
C7	0.01107 (15)	0.28208 (15)	0.48943 (13)	0.0604 (4)
C8	0.10982 (12)	0.31247 (11)	0.56694 (10)	0.0439 (3)
C9	0.23102 (12)	0.26326 (11)	0.57023 (10)	0.0420 (3)
C10	0.27938 (13)	0.25041 (12)	0.47827 (11)	0.0491 (3)
C11	0.39088 (13)	0.20179 (13)	0.48166 (10)	0.0487 (3)
C12	0.45839 (12)	0.16628 (11)	0.57723 (10)	0.0429 (3)
C13	0.41005 (12)	0.17648 (12)	0.66959 (10)	0.0450 (3)
C14	0.29829 (13)	0.22417 (11)	0.66496 (10)	0.0443 (3)
C15	0.66316 (13)	0.11177 (13)	0.66091 (11)	0.0487 (3)
C16	0.86395 (13)	0.05460 (13)	0.71359 (11)	0.0494 (3)
C17	0.88001 (18)	−0.04234 (16)	0.76027 (15)	0.0660 (4)
C18	0.9781 (2)	−0.0575 (2)	0.84284 (17)	0.0798 (6)
C19	1.05668 (18)	0.0220 (2)	0.87639 (15)	0.0776 (6)
C20	1.04112 (16)	0.1173 (2)	0.82793 (17)	0.0751 (6)
C21	0.94430 (16)	0.13453 (15)	0.74553 (15)	0.0618 (4)
H1A	0.3674	0.4894	0.8384	0.087*	0.5
H1B	0.3538	0.4132	0.9316	0.087*	0.5
H1C	0.2992	0.5266	0.928	0.087*	0.5
H1D	0.3128	0.4634	0.9602	0.087*	0.5
H1E	0.3264	0.5396	0.8671	0.087*	0.5
H1F	0.381	0.4262	0.8707	0.087*	0.5
H1N	0.2553 (19)	0.4464 (15)	0.6900 (16)	0.077 (6)*
H2N	0.5943 (17)	0.1095 (15)	0.5116 (16)	0.071 (5)*
H4	−0.0367 (16)	0.4793 (14)	0.6935 (15)	0.065 (5)*
H5	−0.206 (2)	0.4229 (16)	0.5595 (17)	0.085 (6)*
H6	−0.1740 (19)	0.2979 (16)	0.4354 (17)	0.085 (6)*
H7	0.0244 (17)	0.2282 (15)	0.4355 (16)	0.075 (5)*
H10	0.2302 (14)	0.2756 (13)	0.4099 (14)	0.056 (4)*
H11	0.4230 (14)	0.1945 (13)	0.4167 (14)	0.056 (4)*
H13	0.4549 (14)	0.1530 (12)	0.7374 (13)	0.048 (4)*
H14	0.2654 (14)	0.2303 (12)	0.7326 (13)	0.054 (4)*
H17	0.8264 (19)	−0.0942 (19)	0.7374 (17)	0.088 (7)*
H18	0.990 (2)	−0.120 (2)	0.8746 (19)	0.102 (8)*
H19	1.128 (2)	0.0093 (17)	0.9387 (18)	0.088 (6)*
H20	1.100 (2)	0.175 (2)	0.856 (2)	0.117 (9)*
H21	0.934 (2)	0.2006 (19)	0.7127 (19)	0.099 (7)*
N1	0.18901 (11)	0.42823 (10)	0.71585 (9)	0.0472 (3)
N2	0.57348 (11)	0.12143 (11)	0.57576 (9)	0.0520 (3)
O1	0.11529 (11)	0.39476 (12)	0.86327 (9)	0.0741 (4)
O2	0.65950 (10)	0.13264 (12)	0.75166 (8)	0.0693 (4)
O3	0.76480 (10)	0.07135 (11)	0.63069 (8)	0.0671 (3)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C1	0.0528 (9)	0.0687 (10)	0.0506 (8)	−0.0058 (7)	0.0047 (7)	0.0023 (7)
C2	0.0487 (7)	0.0491 (8)	0.0416 (7)	−0.0015 (6)	0.0114 (6)	0.0019 (6)
C3	0.0443 (7)	0.0497 (7)	0.0385 (6)	0.0003 (6)	0.0094 (5)	0.0026 (6)
C4	0.0518 (8)	0.0631 (10)	0.0552 (9)	0.0104 (7)	0.0134 (7)	−0.0016 (7)
C5	0.0463 (9)	0.0891 (13)	0.0663 (10)	0.0199 (9)	0.0028 (7)	0.0008 (9)
C6	0.0496 (9)	0.1016 (15)	0.0592 (10)	0.0129 (9)	−0.0104 (8)	−0.0096 (10)
C7	0.0530 (9)	0.0765 (11)	0.0474 (8)	0.0100 (8)	−0.0021 (7)	−0.0094 (8)
C8	0.0433 (7)	0.0515 (8)	0.0360 (6)	0.0045 (6)	0.0052 (5)	0.0021 (6)
C9	0.0424 (7)	0.0464 (7)	0.0362 (6)	0.0019 (6)	0.0048 (5)	−0.0007 (5)
C10	0.0500 (8)	0.0642 (9)	0.0313 (6)	0.0075 (7)	0.0032 (6)	0.0007 (6)
C11	0.0488 (8)	0.0655 (9)	0.0323 (6)	0.0058 (7)	0.0084 (6)	−0.0027 (6)
C12	0.0416 (7)	0.0495 (7)	0.0373 (6)	0.0022 (6)	0.0068 (5)	−0.0035 (5)
C13	0.0453 (7)	0.0559 (8)	0.0336 (6)	0.0056 (6)	0.0073 (5)	0.0061 (6)
C14	0.0469 (7)	0.0529 (8)	0.0342 (6)	0.0037 (6)	0.0105 (5)	0.0029 (6)
C15	0.0416 (7)	0.0655 (9)	0.0392 (7)	0.0039 (6)	0.0079 (5)	−0.0044 (6)
C16	0.0409 (7)	0.0684 (10)	0.0392 (7)	0.0105 (7)	0.0081 (5)	−0.0024 (6)
C17	0.0696 (11)	0.0615 (10)	0.0682 (11)	0.0009 (9)	0.0160 (9)	−0.0041 (8)
C18	0.0925 (15)	0.0827 (14)	0.0661 (11)	0.0375 (12)	0.0196 (11)	0.0189 (11)
C19	0.0544 (10)	0.1231 (19)	0.0533 (10)	0.0295 (12)	0.0049 (8)	−0.0109 (11)
C20	0.0435 (9)	0.1037 (16)	0.0787 (12)	−0.0032 (10)	0.0128 (8)	−0.0250 (12)
C21	0.0550 (9)	0.0655 (11)	0.0679 (10)	0.0015 (8)	0.0194 (8)	0.0010 (9)
N1	0.0455 (6)	0.0575 (7)	0.0416 (6)	−0.0064 (5)	0.0157 (5)	−0.0054 (5)
N2	0.0444 (6)	0.0767 (9)	0.0346 (6)	0.0120 (6)	0.0061 (5)	−0.0055 (6)
O1	0.0676 (7)	0.1128 (10)	0.0439 (6)	−0.0328 (7)	0.0157 (5)	0.0044 (6)
O2	0.0462 (6)	0.1212 (11)	0.0388 (5)	0.0096 (6)	0.0040 (4)	−0.0165 (6)
O3	0.0488 (6)	0.1116 (10)	0.0397 (5)	0.0235 (6)	0.0051 (4)	−0.0081 (6)

Geometric parameters (Å, º)

C1—H1A	0.96	C14—C13	1.389 (2)
C1—H1B	0.96	C14—C9	1.396 (3)
C1—H1C	0.96	C14—H14	1.006 (16)
C1—H1D	0.96	C15—O2	1.200 (3)
C1—H1E	0.96	C15—O3	1.375 (2)
C1—H1F	0.96	C16—C17	1.369 (3)
C2—C1	1.507 (3)	C16—C21	1.373 (3)
C3—C4	1.397 (3)	C17—C18	1.393 (4)
C4—C5	1.383 (3)	C17—H17	0.91 (2)
C4—H4	0.983 (18)	C18—H18	0.90 (3)
C5—C6	1.376 (3)	C19—C20	1.360 (4)
C5—H5	0.99 (2)	C19—C18	1.360 (4)
C6—H6	0.98 (2)	C19—H19	1.03 (2)
C7—C6	1.392 (3)	C20—H20	1.01 (3)
C7—H7	1.00 (2)	C21—C20	1.386 (4)
C8—C3	1.399 (3)	C21—H21	0.94 (2)
C8—C7	1.400 (3)	N1—C2	1.345 (3)
C9—C10	1.396 (3)	N1—C3	1.431 (3)
C9—C8	1.495 (2)	N1—H1N	0.90 (2)
C10—C11	1.393 (2)	N2—C15	1.346 (3)
C10—H10	0.998 (17)	N2—C12	1.420 (2)
C11—H11	0.971 (17)	N2—H2N	0.91 (2)
C12—C11	1.390 (3)	O1—C2	1.225 (2)
C12—C13	1.397 (3)	O3—C16	1.406 (3)
C13—H13	0.967 (16)
C2—C1—H1A	109.5	C14—C13—H13	119.4 (9)
C2—C1—H1B	109.5	C14—C9—C8	121.21 (16)
C2—C1—H1C	109.5	C15—N2—C12	125.06 (15)
C2—C1—H1D	109.5	C15—N2—H2N	115.9 (12)
C2—C1—H1E	109.5	C15—O3—C16	115.45 (15)
C2—C1—H1F	109.5	C16—C17—C18	118.5 (2)
C2—N1—C3	125.31 (16)	C16—C17—H17	119.4 (14)
C2—N1—H1N	117.5 (13)	C16—C21—C20	119.4 (2)
C3—C4—H4	117.3 (11)	C16—C21—H21	120.6 (14)
C3—C8—C7	117.31 (15)	C17—C16—C21	120.86 (19)
C3—C8—C9	122.41 (15)	C17—C16—O3	119.22 (16)
C3—N1—H1N	116.5 (13)	C17—C18—H18	119.9 (16)
C4—C3—C8	120.66 (16)	C18—C17—H17	122.0 (14)
C4—C3—N1	119.87 (16)	C18—C19—H19	119.4 (12)
C4—C5—H5	121.2 (12)	C19—C18—C17	120.9 (2)
C5—C4—C3	120.56 (18)	C19—C18—H18	119.2 (16)
C5—C4—H4	122.2 (11)	C19—C20—C21	120.3 (2)
C5—C6—C7	119.71 (19)	C19—C20—H20	117.7 (15)
C5—C6—H6	118.5 (12)	C20—C19—C18	120.0 (2)
C6—C5—C4	119.83 (17)	C20—C19—H19	120.6 (12)
C6—C5—H5	119.0 (12)	C20—C21—H21	120.0 (15)
C6—C7—C8	121.87 (18)	C21—C16—O3	119.91 (17)
C6—C7—H7	119.7 (11)	C21—C20—H20	122.0 (15)
C7—C6—H6	121.7 (12)	H1A—C1—H1B	109.5
C7—C8—C9	120.26 (16)	H1A—C1—H1C	109.5
C8—C3—N1	119.40 (14)	H1A—C1—H1D	141.1
C8—C7—H7	118.4 (11)	H1A—C1—H1E	56.3
C9—C10—H10	117.6 (9)	H1A—C1—H1F	56.3
C9—C14—H14	119.5 (9)	H1B—C1—H1C	109.5
C10—C11—H11	119.5 (10)	H1B—C1—H1D	56.3
C10—C9—C14	117.20 (16)	H1B—C1—H1E	141.1
C10—C9—C8	121.54 (16)	H1B—C1—H1F	56.3
C11—C10—C9	121.13 (16)	H1C—C1—H1D	56.3
C11—C10—H10	121.3 (9)	H1C—C1—H1E	56.3
C11—C12—C13	118.66 (16)	H1C—C1—H1F	141.1
C11—C12—N2	118.01 (16)	H1D—C1—H1E	109.5
C12—C11—C10	120.89 (16)	H1D—C1—H1F	109.5
C12—C11—H11	119.5 (10)	H1E—C1—H1F	109.5
C12—C13—H13	120.7 (9)	N1—C2—C1	115.96 (17)
C12—N2—H2N	118.0 (12)	N2—C15—O3	110.12 (16)
C13—C12—N2	123.33 (16)	O1—C2—C1	122.82 (16)
C13—C14—C9	122.24 (16)	O1—C2—N1	121.22 (17)
C13—C14—H14	118.2 (9)	O2—C15—N2	127.43 (17)
C14—C13—C12	119.84 (16)	O2—C15—O3	122.44 (17)
C2—N1—C3—C4	58.4 (2)	C13—C14—C9—C10	1.5 (2)
C2—N1—C3—C8	−124.6 (2)	C13—C14—C9—C8	178.8 (1)
C3—C4—C5—C6	−1.4 (3)	C14—C9—C10—C11	−0.8 (2)
C3—C8—C7—C6	−2.4 (3)	C14—C9—C8—C3	47.6 (2)
C3—N1—C2—C1	176.2 (1)	C14—C9—C8—C7	−131.2 (2)
C3—N1—C2—O1	−3.3 (2)	C15—N2—C12—C11	159.5 (2)
C4—C5—C6—C7	1.2 (3)	C15—N2—C12—C13	−20.4 (2)
C7—C8—C3—C4	2.2 (2)	C15—O3—C16—C17	93.9 (2)
C7—C8—C3—N1	−174.7 (1)	C15—O3—C16—C21	−87.1 (2)
C8—C3—C4—C5	−0.4 (2)	C16—C17—C18—C19	−0.2 (3)
C8—C7—C6—C5	0.8 (3)	C16—C21—C20—C19	0.3 (3)
C8—C9—C10—C11	−178.2 (1)	C17—C16—C21—C20	−1.6 (2)
C9—C10—C11—C12	−1.2 (2)	C18—C19—C20—C21	1.1 (3)
C9—C14—C13—C12	−0.1 (2)	C20—C19—C18—C17	−1.1 (3)
C9—C8—C3—C4	−176.5 (1)	C21—C16—C17—C18	1.6 (3)
C9—C8—C3—N1	6.5 (2)	N1—C3—C4—C5	176.6 (1)
C9—C8—C7—C6	176.3 (2)	N2—C12—C11—C10	−177.4 (1)
C10—C9—C8—C3	−135.2 (2)	N2—C12—C13—C14	178.0 (1)
C10—C9—C8—C7	46.1 (2)	N2—C15—O3—C16	−178.2 (1)
C11—C12—C13—C14	−1.9 (2)	O2—C15—O3—C16	0.9 (2)
C12—N2—C15—O2	4.9 (3)	O3—C16—C17—C18	−179.5 (1)
C12—N2—C15—O3	−176.1 (1)	O3—C16—C21—C20	179.5 (1)
C13—C12—C11—C10	2.5 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N2—H2N···O1^i	0.91 (2)	1.96 (2)	2.855 (5)	169 (2)
C1—H1D···O3^ii	0.96	2.39	3.328 (6)	166
C4—H4···O2^iii	0.98 (2)	2.57 (2)	3.434 (6)	147 (1)
C10—H10···O2^iv	0.99 (2)	2.35 (2)	3.318 (6)	164 (1)
C11—H11···O1^i	0.97 (2)	2.65 (2)	3.410 (6)	136 (1)

Symmetry codes: (i) x+1/2, −y+1/2, z−1/2; (ii) x−1/2, −y+1/2, z+1/2; (iii) −x+1/2, y+1/2, −z+3/2; (iv) x−1/2, −y+1/2, z−1/2.