(E)-N,N-Diethyl-3-hydr­oxy-3,5-diphenyl­pent-4-enamide

The title compound, C₂₁H₂₅NO₂, was synthesized by a Reformatsky-type reaction. In the mol­ecule, the dihedral angle between the two phenyl rings is 66.1 (1)° and the crystal packing exhibits no classical hydrogen bonds.

Key indicators

• Single-crystal X-ray study
• T = 294 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.054
• wR factor = 0.202
• Data-to-parameter ratio = 14.9

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT026_ALERT_3_C Ratio Observed / Unique Reflections too Low ....         45 Perc.
PLAT066_ALERT_1_C Predicted and Reported Transmissions Identical .          ?
PLAT150_ALERT_1_C Volume as Calculated Differs from that Given ...    3741.00 Ang-3
PLAT230_ALERT_2_C Hirshfeld Test Diff for    N1     -   C20     ..       6.39 su
PLAT230_ALERT_2_C Hirshfeld Test Diff for    C12    -   C13     ..       6.22 su
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for         C6
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        C18
PLAT340_ALERT_3_C Low Bond Precision on C-C bonds (x 1000) Ang ...          6

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

   2 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
   2 ALERT type 3 Indicator that the structure quality may be low
   0 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

The Reformatsky reaction provides a good strategy of carbon-carbon bond formation (Ocamp & Doliber, 2004). In our study on the Reformatsky-type reaction of α-bromoacetamide with α,β-unsaturated ketone, we found that the most attractive feature of the reaction is its chemoselectivity, and a new compound, (I), has been synthesized by reaction of 1,3-diphenyl-propenone with N,N-diethyl-2-bromoacetamide. The structure determination of compound (I) was undertaken and the results are presented here.

The bond distances and angles are in good agreement with those respective normal values. In compound (I), the dihedral angle between the two phenyl rings is 113.9 (1)°, and the carbon-carbon double bond adopts E-configuration, which is also confirmed by the respective coupling constant (J = 16 Hz) in the ¹H NMR spectroscopy of compound (I). The torsion angle of C6—C7—C8 —C9 is -179.3 (3) °, which indicates that they are approximately coplannar. The bond distance of C17—N1 [1.334 (4) Å] is significantly shorter than those of C18—N1 [1.482 (4) Å] and C20—N1 [1.487 (5) Å] because of \p-π conjugation.

Related literature

For related literature, see: Ocamp & Doliber (2004).

S2. Experimental

To a solution of 1,3-diphenyl-propenone (1 mmol) in dichloromethane (5 ml), N,N-diethyl-2-bromoacetamide (2 mmol), zinc powder (3 mmol) and a trace amount of iodine were added to the mixture in order. The reaction mixture was refluxed with stirring for 5 h and then quenched with a saturated solution of ammonium chloride (8 ml). The mixture was filtered and extracted with dichloromethane, dried over magnesium sulfate. After evaporation of the solvent, a white solid was obtained (0.236 g, yield 73%) by column chromatography (silica gel/petroleum ether-ethyl acetate = 7/3, v/v). The colorless single crystals of compound was obtained through the evaporation of ethyl acetate-petroleum ether. Spectroscopic analysis: IR (KBr, νcm^-1):3293, 1613; ¹H NMR (CDCl₃, δ, p.p.m.): 7.54–7.18 (m, 10H), 6.82 (s, 1H), 6.67 (d, 1H), 6.47 (d, 1H), 3.29 (m, 4H), 2.99 (d, 1H), 2.90 (d, 1H), 1.16 (t, 3H), 0.98 (t, 3H).

S3. Refinement

All carbon H atoms were positioned geometrically and refined as riding (C—H = 0.93 - 0.97 Å). For the CH and CH₂ groups, U_iso(H) values were set equal to 1.2U_eq(C) and for the methyl groups, they were set equal to 1.5U_eq(C). Atom H1 was refined with O1—H1 = 0.82 Å and U_iso(H) = 1.5U_eq(O).

Computing details

Data collection: SMART (Bruker, 1997); cell refinement: SAINT (Bruker, 1997; data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 1997); software used to prepare material for publication: SHELXTL.

Figures

Fig. 1. View of the molecule of (I), showing the atom-labelling scheme. Displacement ellipsoids are drawn at the 30% probability level.

(E)—N,N-Diethyl-3-hydroxy-3,5-diphenylpent-4-enamide

Crystal data

C21H25NO2	Dx = 1.149 Mg m^−3
Mr = 323.42	Melting point: 318 K
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 1542 reflections
a = 10.156 (3) Å	θ = 2.3–20.5°
b = 10.339 (4) Å	µ = 0.07 mm^−1
c = 35.621 (12) Å	T = 294 K
V = 3741 (2) Å^3	Needle, colourless
Z = 8	0.22 × 0.20 × 0.16 mm
F(000) = 1392

Data collection

Bruker SMART CCD area-detector diffractometer	3271 independent reflections
Radiation source: fine-focus sealed tube	1480 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.060
φ and ω scans	θmax = 25.0°, θmin = 1.1°
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	h = −11→11
Tmin = 0.984, Tmax = 0.988	k = −12→5
11761 measured reflections	l = −42→34

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)] = 0.054	Hydrogen site location: inferred from neighbouring sites
wR(F^2) = 0.202	H-atom parameters constrained
S = 1.03	w = 1/[σ^2(Fo^2) + (0.0596P)^2 + 0.1641P] where P = (Fo^2 + 2Fc^2)/3
3271 reflections	(Δ/σ)max < 0.001
220 parameters	Δρmax = 0.14 e Å^−3
12 restraints	Δρmin = −0.15 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
O1	−0.0108 (2)	0.4384 (2)	0.34952 (6)	0.0708 (7)
H1	−0.0179	0.4120	0.3279	0.106*
O2	0.0823 (3)	0.2997 (3)	0.29268 (6)	0.0793 (8)
N1	0.2939 (3)	0.2396 (3)	0.29241 (7)	0.0690 (9)
C1	0.1788 (4)	0.5408 (4)	0.48042 (10)	0.0810 (12)
H1A	0.2237	0.4649	0.4747	0.097*
C2	0.2020 (4)	0.6018 (5)	0.51398 (11)	0.0945 (14)
H2	0.2622	0.5666	0.5308	0.113*
C3	0.1385 (5)	0.7126 (5)	0.52296 (12)	0.0944 (14)
H3	0.1554	0.7532	0.5458	0.113*
C4	0.0503 (5)	0.7645 (4)	0.49870 (13)	0.0993 (15)
H4	0.0064	0.8406	0.5048	0.119*
C5	0.0261 (4)	0.7036 (4)	0.46502 (10)	0.0831 (12)
H5	−0.0348	0.7394	0.4485	0.100*
C6	0.0898 (3)	0.5906 (3)	0.45503 (8)	0.0592 (9)
C7	0.0603 (3)	0.5289 (4)	0.41901 (8)	0.0621 (9)
H7	0.0076	0.5752	0.4024	0.074*
C8	0.1004 (3)	0.4155 (4)	0.40781 (8)	0.0586 (9)
H8	0.1524	0.3686	0.4244	0.070*
C9	0.0707 (3)	0.3528 (3)	0.37033 (8)	0.0546 (9)
C10	0.0025 (3)	0.2238 (3)	0.37714 (8)	0.0536 (9)
C11	0.0664 (4)	0.1252 (4)	0.39667 (10)	0.0740 (11)
H11	0.1530	0.1382	0.4043	0.089*
C12	0.0074 (6)	0.0114 (5)	0.40498 (12)	0.0988 (14)
H12	0.0531	−0.0519	0.4182	0.119*
C13	−0.1177 (7)	−0.0099 (5)	0.39410 (13)	0.1073 (17)
H13	−0.1579	−0.0882	0.3999	0.129*
C14	−0.1873 (4)	0.0831 (6)	0.37449 (12)	0.0945 (15)
H14	−0.2736	0.0679	0.3670	0.113*
C15	−0.1249 (4)	0.2011 (4)	0.36615 (9)	0.0746 (11)
H15	−0.1707	0.2645	0.3530	0.089*
C16	0.2026 (3)	0.3355 (4)	0.34956 (8)	0.0631 (10)
H16A	0.2484	0.4178	0.3492	0.076*
H16B	0.2566	0.2747	0.3634	0.076*
C17	0.1878 (4)	0.2876 (3)	0.30959 (9)	0.0565 (9)
C18	0.2871 (4)	0.2085 (4)	0.25183 (9)	0.0767 (11)
H18A	0.2266	0.2676	0.2396	0.092*
H18B	0.3733	0.2203	0.2407	0.092*
C19	0.2427 (5)	0.0740 (4)	0.24549 (13)	0.1223 (17)
H19A	0.3028	0.0152	0.2574	0.183*
H19B	0.2400	0.0567	0.2190	0.183*
H19C	0.1563	0.0627	0.2560	0.183*
C20	0.4265 (5)	0.2287 (5)	0.30977 (11)	0.1050 (17)
H20A	0.4744	0.1586	0.2979	0.126*
H20B	0.4170	0.2078	0.3362	0.126*
C21	0.5042 (5)	0.3523 (7)	0.30588 (13)	0.133 (2)
H21A	0.5124	0.3741	0.2798	0.199*
H21B	0.5902	0.3406	0.3165	0.199*
H21C	0.4595	0.4208	0.3188	0.199*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0724 (17)	0.0813 (17)	0.0586 (13)	0.0152 (13)	−0.0094 (13)	−0.0002 (12)
O2	0.0540 (16)	0.129 (2)	0.0554 (13)	−0.0034 (15)	−0.0014 (12)	−0.0159 (14)
N1	0.065 (2)	0.088 (2)	0.0539 (16)	0.0176 (17)	0.0032 (16)	−0.0027 (14)
C1	0.083 (3)	0.098 (3)	0.062 (2)	0.011 (2)	−0.008 (2)	−0.019 (2)
C2	0.098 (4)	0.124 (4)	0.062 (2)	0.000 (3)	−0.009 (2)	−0.020 (3)
C3	0.103 (4)	0.114 (4)	0.067 (3)	−0.033 (3)	0.016 (3)	−0.028 (3)
C4	0.124 (4)	0.079 (3)	0.095 (3)	−0.002 (3)	0.008 (3)	−0.030 (3)
C5	0.102 (3)	0.073 (3)	0.075 (2)	0.002 (2)	−0.005 (2)	−0.010 (2)
C6	0.061 (2)	0.066 (2)	0.0509 (18)	−0.0086 (19)	0.0087 (18)	−0.0026 (17)
C7	0.062 (2)	0.070 (3)	0.0534 (19)	−0.003 (2)	−0.0007 (17)	0.0001 (18)
C8	0.054 (2)	0.073 (3)	0.0491 (18)	−0.0012 (19)	0.0007 (15)	−0.0031 (17)
C9	0.0411 (19)	0.075 (2)	0.0479 (17)	0.0050 (18)	−0.0027 (15)	−0.0011 (16)
C10	0.045 (2)	0.072 (2)	0.0440 (16)	−0.0017 (19)	0.0070 (16)	−0.0115 (17)
C11	0.072 (3)	0.080 (3)	0.070 (2)	−0.008 (2)	0.001 (2)	−0.002 (2)
C12	0.121 (4)	0.092 (4)	0.083 (3)	−0.014 (3)	0.001 (3)	−0.002 (3)
C13	0.153 (6)	0.101 (4)	0.067 (3)	−0.036 (4)	0.029 (3)	−0.006 (3)
C14	0.070 (3)	0.135 (4)	0.078 (3)	−0.044 (3)	0.019 (2)	−0.036 (3)
C15	0.054 (2)	0.107 (3)	0.063 (2)	−0.004 (2)	0.0058 (19)	−0.017 (2)
C16	0.050 (2)	0.087 (3)	0.0518 (18)	−0.0079 (19)	0.0039 (16)	−0.0057 (17)
C17	0.049 (2)	0.068 (2)	0.0527 (19)	−0.0041 (19)	0.0037 (18)	0.0024 (17)
C18	0.082 (3)	0.086 (3)	0.062 (2)	0.011 (2)	0.009 (2)	−0.002 (2)
C19	0.182 (5)	0.084 (3)	0.101 (3)	0.009 (3)	−0.002 (3)	−0.015 (3)
C20	0.099 (4)	0.151 (5)	0.065 (2)	0.061 (4)	0.006 (3)	0.000 (3)
C21	0.080 (3)	0.210 (6)	0.108 (3)	−0.008 (4)	−0.001 (3)	−0.037 (4)

Geometric parameters (Å, º)

O1—C9	1.421 (4)	C10—C11	1.395 (5)
O1—H1	0.8200	C11—C12	1.353 (6)
O2—C17	1.235 (4)	C11—H11	0.9300
N1—C17	1.334 (4)	C12—C13	1.347 (6)
N1—C18	1.482 (4)	C12—H12	0.9300
N1—C20	1.487 (5)	C13—C14	1.382 (6)
C1—C2	1.372 (5)	C13—H13	0.9300
C1—C6	1.378 (5)	C14—C15	1.406 (6)
C1—H1A	0.9300	C14—H14	0.9300
C2—C3	1.353 (6)	C15—H15	0.9300
C2—H2	0.9300	C16—C17	1.515 (4)
C3—C4	1.356 (6)	C16—H16A	0.9700
C3—H3	0.9300	C16—H16B	0.9700
C4—C5	1.377 (5)	C18—C19	1.480 (5)
C4—H4	0.9300	C18—H18A	0.9700
C5—C6	1.382 (5)	C18—H18B	0.9700
C5—H5	0.9300	C19—H19A	0.9600
C6—C7	1.464 (4)	C19—H19B	0.9600
C7—C8	1.303 (4)	C19—H19C	0.9600
C7—H7	0.9300	C20—C21	1.508 (7)
C8—C9	1.515 (4)	C20—H20A	0.9700
C8—H8	0.9300	C20—H20B	0.9700
C9—C10	1.521 (5)	C21—H21A	0.9600
C9—C16	1.540 (4)	C21—H21B	0.9600
C10—C15	1.373 (5)	C21—H21C	0.9600
C9—O1—H1	109.5	C12—C13—C14	120.9 (5)
C17—N1—C18	119.3 (3)	C12—C13—H13	119.5
C17—N1—C20	124.7 (3)	C14—C13—H13	119.5
C18—N1—C20	115.6 (3)	C13—C14—C15	118.7 (4)
C2—C1—C6	120.8 (4)	C13—C14—H14	120.7
C2—C1—H1A	119.6	C15—C14—H14	120.7
C6—C1—H1A	119.6	C10—C15—C14	120.9 (4)
C3—C2—C1	120.9 (4)	C10—C15—H15	119.6
C3—C2—H2	119.6	C14—C15—H15	119.6
C1—C2—H2	119.6	C17—C16—C9	113.8 (3)
C2—C3—C4	120.0 (4)	C17—C16—H16A	108.8
C2—C3—H3	120.0	C9—C16—H16A	108.8
C4—C3—H3	120.0	C17—C16—H16B	108.8
C3—C4—C5	119.5 (4)	C9—C16—H16B	108.8
C3—C4—H4	120.2	H16A—C16—H16B	107.7
C5—C4—H4	120.2	O2—C17—N1	120.9 (3)
C4—C5—C6	121.8 (4)	O2—C17—C16	120.7 (3)
C4—C5—H5	119.1	N1—C17—C16	118.2 (3)
C6—C5—H5	119.1	C19—C18—N1	111.6 (3)
C1—C6—C5	117.0 (3)	C19—C18—H18A	109.3
C1—C6—C7	123.1 (3)	N1—C18—H18A	109.3
C5—C6—C7	119.9 (3)	C19—C18—H18B	109.3
C8—C7—C6	126.6 (3)	N1—C18—H18B	109.3
C8—C7—H7	116.7	H18A—C18—H18B	108.0
C6—C7—H7	116.7	C18—C19—H19A	109.5
C7—C8—C9	126.4 (3)	C18—C19—H19B	109.5
C7—C8—H8	116.8	H19A—C19—H19B	109.5
C9—C8—H8	116.8	C18—C19—H19C	109.5
O1—C9—C8	108.0 (3)	H19A—C19—H19C	109.5
O1—C9—C10	111.3 (3)	H19B—C19—H19C	109.5
C8—C9—C10	109.0 (2)	N1—C20—C21	111.8 (4)
O1—C9—C16	109.2 (2)	N1—C20—H20A	109.3
C8—C9—C16	107.4 (2)	C21—C20—H20A	109.3
C10—C9—C16	111.8 (3)	N1—C20—H20B	109.3
C15—C10—C11	117.1 (4)	C21—C20—H20B	109.3
C15—C10—C9	122.3 (3)	H20A—C20—H20B	107.9
C11—C10—C9	120.6 (3)	C20—C21—H21A	109.5
C12—C11—C10	122.6 (4)	C20—C21—H21B	109.5
C12—C11—H11	118.7	H21A—C21—H21B	109.5
C10—C11—H11	118.7	C20—C21—H21C	109.5
C13—C12—C11	119.8 (5)	H21A—C21—H21C	109.5
C13—C12—H12	120.1	H21B—C21—H21C	109.5
C11—C12—H12	120.1
C6—C1—C2—C3	−0.2 (6)	C9—C10—C11—C12	176.7 (3)
C1—C2—C3—C4	0.2 (7)	C10—C11—C12—C13	0.3 (6)
C2—C3—C4—C5	0.0 (7)	C11—C12—C13—C14	0.0 (6)
C3—C4—C5—C6	−0.3 (7)	C12—C13—C14—C15	−0.2 (6)
C2—C1—C6—C5	0.0 (5)	C11—C10—C15—C14	0.1 (5)
C2—C1—C6—C7	−179.4 (3)	C9—C10—C15—C14	−176.8 (3)
C4—C5—C6—C1	0.3 (6)	C13—C14—C15—C10	0.1 (5)
C4—C5—C6—C7	179.7 (4)	O1—C9—C16—C17	−56.6 (4)
C1—C6—C7—C8	8.0 (6)	C8—C9—C16—C17	−173.4 (3)
C5—C6—C7—C8	−171.4 (4)	C10—C9—C16—C17	67.0 (4)
C6—C7—C8—C9	−179.3 (3)	C18—N1—C17—O2	4.0 (5)
C7—C8—C9—O1	−0.9 (5)	C20—N1—C17—O2	176.3 (4)
C7—C8—C9—C10	−122.0 (4)	C18—N1—C17—C16	−171.8 (3)
C7—C8—C9—C16	116.7 (4)	C20—N1—C17—C16	0.5 (5)
O1—C9—C10—C15	−4.0 (4)	C9—C16—C17—O2	20.4 (5)
C8—C9—C10—C15	115.1 (3)	C9—C16—C17—N1	−163.8 (3)
C16—C9—C10—C15	−126.3 (3)	C17—N1—C18—C19	−89.5 (4)
O1—C9—C10—C11	179.2 (3)	C20—N1—C18—C19	97.5 (4)
C8—C9—C10—C11	−61.8 (4)	C17—N1—C20—C21	−85.4 (4)
C16—C9—C10—C11	56.8 (4)	C18—N1—C20—C21	87.2 (4)
C15—C10—C11—C12	−0.3 (5)