(S)-N-(1-Hydroxy­methyl-2-methyl­prop­yl)-2-methoxy­benzamide

The title compound, C₁₃H₁₉NO₃, is an important synthetic inter­mediate. Weak O—H...O and N—H...O hydrogen bonds enhance the stability of the crystal structure.

Key indicators

• Single-crystal X-ray study
• T = 291 K
• Mean [sigma](C-C) = 0.006 Å
• R factor = 0.046
• wR factor = 0.136
• Data-to-parameter ratio = 8.5

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT029_ALERT_3_C _diffrn_measured_fraction_theta_full Low .......       0.98
PLAT153_ALERT_1_C The su's on the Cell Axes   are Equal (x 100000)        400 Ang.
PLAT242_ALERT_2_C Check Low       Ueq as Compared to Neighbors for        C11
PLAT340_ALERT_3_C Low Bond Precision on C-C Bonds (x 1000) Ang ...          6
PLAT720_ALERT_4_C Number of Unusual/Non-Standard Label(s) ........          1

Alert level G
REFLT03_ALERT_4_G Please check that the estimate of the number of Friedel pairs is
            correct. If it is not, please give the correct count in the
            _publ_section_exptl_refinement section of the submitted CIF.
           From the CIF: _diffrn_reflns_theta_max           25.53
           From the CIF: _reflns_number_total               1397
           Count of symmetry unique reflns         1425
           Completeness (_total/calc)             98.04%
           TEST3: Check Friedels for noncentro structure
           Estimate of Friedel pairs measured         0
           Fraction of Friedel pairs measured     0.000
           Are heavy atom types Z>Si present         no
PLAT791_ALERT_1_G Confirm the Absolute Configuration of C9     ...          S

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

   2 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   1 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
   2 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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S1. Comment

Oxazoline ligands have been proved to be a class of chiral ligands, being capable of forming a broad variety of metal complexes that are capable of catalyzing a great number of reactions with excellent enantioselectivity (Rechavi & Lemaire, 2002). It is believed that the oxazoline ring can be modified structurally by replacing the O atom with a substituted N atom, leading to new types of imidazoline ligands (Ma & You, 2007). However, all those ligands can prepared by this compound as an intermediate. Herein, we report the synthesis and structure of the title compound (I).

As shown in Fig. 1, there is a chiral center at C9 derived from L-valinol. The C—N bond lengths are 1.318 (4) Å and 1.463 (4) Å, and the C8—N1—C9 angle is 125.3 (3) °. A combination of O—H···O and N—H···O hydrogen bonds interactions provide packing forces in the crystal structure of the title compound.

Related literature

For related literature, see: Ma & You (2007); Rechavi & Lemaire (2002).

S2. Experimental

NaH (8.7 g, 60%, 0.216 mol) was added portionwise to a stirred solution of L-valinol (22.1 g, 0.215 mol) in dry THF (120 ml). The mixture was stirred at ambient temperature for 1 h. To this solution was added 2-Methoxy-benzoic acid methyl ester (17.8 g, 0.107 mol) dissolved in THF (50 ml). The mixture was refluxed for 12 h under nitrogen, quenched with H₂O (10 ml) and concentrated by evaporation of the solvent. The residue was dissolved in CH₂Cl₂ (100 ml), washed with H₂O, brine, and dried over MgSO₄. And then removal of the solvent in vacuo gave a white solid, which was recrystallized from ethyl acetate and petroleum ether to afford the title compound as white crystals (22.8 g, 90%).

S3. Refinement

H atoms were positioned geometrically and refined in the riding model approximation with O—H = 0.82 Å, N—H = 0.86 Å, and C—H = 0.93, 0.96, 0.97 or 0.98 Å. The U_iso(H) = 1.5 U_eq(C) for the CH₃ while it was set to 1.2 U_eq(C,N,O) for all other H atoms. Due to abscence of significant anomalous dispersion effects, the reflection data were merged.

Computing details

Data collection: DIFRAC (Gabe & White, 1993); cell refinement: DIFRAC (Gabe & White, 1993); data reduction: NRCVAX (Gabe et al., 1989); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008); molecular graphics: ORTEPIII (Burnett & Johnson, 1996); software used to prepare material for publication: SHELXL97 (Sheldrick, 2008).

Figures

Fig. 1. The molecular structure of (I), showing 30% probability displacement ellipsoids and the atomic numbering.

(S)-N-(1-Hydroxymethyl-2-methylpropyl)-2-methoxybenzamide

Crystal data

C13H19NO3	F(000) = 512
Mr = 237.29	Dx = 1.202 Mg m^−3
Orthorhombic, P212121	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2ab	Cell parameters from 25 reflections
a = 9.015 (4) Å	θ = 4.5–6.7°
b = 10.386 (4) Å	µ = 0.09 mm^−1
c = 14.005 (4) Å	T = 291 K
V = 1311.3 (9) Å^3	Block, colourless
Z = 4	0.50 × 0.44 × 0.40 mm

Data collection

Enraf–Nonius CAD-4 diffractometer	Rint = 0.010
Radiation source: fine-focus sealed tube	θmax = 25.5°, θmin = 2.4°
Graphite monochromator	h = −3→10
ω/2θ scans	k = −3→12
1457 measured reflections	l = −5→16
1397 independent reflections	3 standard reflections every 120 reflections
848 reflections with I > 2σ(I)	intensity decay: 0.4%

Refinement

Refinement on F^2	Secondary atom site location: difference Fourier map
Least-squares matrix: full	Hydrogen site location: inferred from neighbouring sites
R[F^2 > 2σ(F^2)] = 0.045	H-atom parameters constrained
wR(F^2) = 0.136	w = 1/[σ^2(Fo^2) + (0.0778P)^2 + 0.0096P] where P = (Fo^2 + 2Fc^2)/3
S = 1.02	(Δ/σ)max < 0.001
1397 reflections	Δρmax = 0.21 e Å^−3
164 parameters	Δρmin = −0.14 e Å^−3
0 restraints	Extinction correction: SHELXL97 (Sheldrick, 2008), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.069 (8)

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	0.1432 (3)	0.3872 (3)	0.16126 (19)	0.0666 (8)
O2	0.5192 (3)	0.3286 (3)	−0.00264 (18)	0.0703 (8)
O3	0.2632 (4)	0.0046 (3)	−0.0111 (2)	0.0810 (10)
H3	0.1945	0.0562	−0.0140	0.097*
N1	0.3536 (3)	0.2340 (2)	0.0926 (2)	0.0487 (8)
H1N1	0.2711	0.2433	0.1227	0.058*
C1	0.1842 (4)	0.4786 (3)	0.0963 (3)	0.0514 (9)
C2	0.1074 (5)	0.5935 (4)	0.0851 (3)	0.0709 (12)
H2	0.0240	0.6099	0.1223	0.085*
C3	0.1535 (6)	0.6826 (4)	0.0201 (4)	0.0878 (16)
H3A	0.1009	0.7591	0.0133	0.105*
C4	0.2760 (6)	0.6610 (4)	−0.0355 (4)	0.0929 (18)
H4	0.3078	0.7226	−0.0791	0.112*
C5	0.3519 (5)	0.5457 (4)	−0.0255 (3)	0.0745 (13)
H5	0.4337	0.5300	−0.0642	0.089*
C6	0.3096 (4)	0.4533 (3)	0.0402 (3)	0.0489 (9)
C7	0.0018 (6)	0.3961 (7)	0.2048 (3)	0.109 (2)
H7A	−0.0038	0.4739	0.2416	0.163*
H7B	−0.0130	0.3233	0.2460	0.163*
H7C	−0.0735	0.3970	0.1564	0.163*
C8	0.4020 (4)	0.3328 (3)	0.0425 (2)	0.0459 (9)
C9	0.4288 (4)	0.1097 (3)	0.1012 (2)	0.0456 (8)
H9	0.5050	0.1060	0.0514	0.055*
C10	0.3202 (5)	0.0025 (3)	0.0824 (3)	0.0609 (10)
H10A	0.3691	−0.0794	0.0932	0.073*
H10B	0.2387	0.0091	0.1273	0.073*
C11	0.5075 (5)	0.0978 (4)	0.1981 (3)	0.0632 (11)
H11	0.5515	0.0115	0.2002	0.076*
C12	0.6339 (6)	0.1925 (5)	0.2074 (4)	0.0939 (16)
H12A	0.5957	0.2787	0.2045	0.141*
H12B	0.7031	0.1794	0.1562	0.141*
H12C	0.6832	0.1796	0.2674	0.141*
C13	0.4068 (6)	0.1084 (6)	0.2833 (3)	0.107 (2)
H13A	0.4630	0.0946	0.3406	0.160*
H13B	0.3299	0.0447	0.2788	0.160*
H13C	0.3631	0.1926	0.2849	0.160*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0560 (16)	0.0735 (18)	0.0704 (16)	0.0177 (16)	0.0102 (13)	0.0020 (15)
O2	0.0553 (16)	0.0652 (18)	0.0903 (18)	−0.0022 (15)	0.0249 (16)	0.0137 (16)
O3	0.072 (2)	0.071 (2)	0.099 (2)	0.0007 (16)	−0.0180 (18)	−0.0113 (17)
N1	0.0369 (15)	0.0481 (16)	0.0610 (17)	0.0057 (15)	0.0078 (14)	0.0039 (14)
C1	0.050 (2)	0.046 (2)	0.058 (2)	−0.0001 (18)	−0.0117 (19)	−0.0054 (18)
C2	0.064 (3)	0.060 (3)	0.089 (3)	0.015 (2)	−0.016 (2)	−0.019 (2)
C3	0.070 (3)	0.048 (2)	0.146 (4)	0.002 (2)	−0.043 (3)	0.008 (3)
C4	0.067 (3)	0.059 (3)	0.152 (5)	−0.011 (3)	−0.030 (3)	0.047 (3)
C5	0.053 (2)	0.066 (2)	0.104 (3)	−0.010 (2)	−0.011 (2)	0.031 (3)
C6	0.044 (2)	0.0442 (18)	0.059 (2)	−0.0051 (17)	−0.0149 (17)	0.0013 (17)
C7	0.077 (3)	0.156 (6)	0.094 (3)	0.036 (4)	0.030 (3)	0.020 (4)
C8	0.037 (2)	0.046 (2)	0.054 (2)	−0.0041 (17)	−0.0023 (16)	0.0044 (18)
C9	0.0387 (18)	0.0447 (19)	0.0534 (19)	0.0069 (17)	0.0040 (15)	−0.0004 (17)
C10	0.053 (2)	0.050 (2)	0.080 (3)	0.0044 (19)	0.000 (2)	0.004 (2)
C11	0.062 (3)	0.061 (3)	0.067 (2)	0.016 (2)	−0.009 (2)	0.011 (2)
C12	0.096 (3)	0.093 (3)	0.093 (3)	0.000 (3)	−0.037 (3)	−0.011 (3)
C13	0.120 (4)	0.146 (5)	0.054 (2)	0.031 (5)	0.004 (3)	0.016 (3)

Geometric parameters (Å, º)

O1—C1	1.365 (4)	C6—C8	1.504 (5)
O1—C7	1.416 (5)	C7—H7A	0.9600
O2—C8	1.232 (4)	C7—H7B	0.9600
O3—C10	1.406 (5)	C7—H7C	0.9600
O3—H3	0.8200	C9—C10	1.506 (5)
N1—C8	1.318 (4)	C9—C11	1.537 (5)
N1—C9	1.463 (4)	C9—H9	0.9800
N1—H1N1	0.8600	C10—H10A	0.9700
C1—C2	1.389 (5)	C10—H10B	0.9700
C1—C6	1.402 (5)	C11—C13	1.503 (6)
C2—C3	1.363 (6)	C11—C12	1.511 (6)
C2—H2	0.9300	C11—H11	0.9800
C3—C4	1.369 (7)	C12—H12A	0.9600
C3—H3A	0.9300	C12—H12B	0.9600
C4—C5	1.386 (6)	C12—H12C	0.9600
C4—H4	0.9300	C13—H13A	0.9600
C5—C6	1.383 (5)	C13—H13B	0.9600
C5—H5	0.9300	C13—H13C	0.9600
C1—O1—C7	119.1 (4)	N1—C8—C6	118.4 (3)
C10—O3—H3	109.5	N1—C9—C10	109.7 (3)
C8—N1—C9	125.3 (3)	N1—C9—C11	111.0 (3)
C8—N1—H1N1	117.4	C10—C9—C11	113.3 (3)
C9—N1—H1N1	117.4	N1—C9—H9	107.5
O1—C1—C2	122.5 (4)	C10—C9—H9	107.5
O1—C1—C6	117.5 (3)	C11—C9—H9	107.5
C2—C1—C6	120.0 (4)	O3—C10—C9	112.9 (3)
C3—C2—C1	120.4 (4)	O3—C10—H10A	109.0
C3—C2—H2	119.8	C9—C10—H10A	109.0
C1—C2—H2	119.8	O3—C10—H10B	109.0
C2—C3—C4	121.0 (4)	C9—C10—H10B	109.0
C2—C3—H3A	119.5	H10A—C10—H10B	107.8
C4—C3—H3A	119.5	C13—C11—C12	109.8 (4)
C3—C4—C5	118.8 (4)	C13—C11—C9	114.6 (3)
C3—C4—H4	120.6	C12—C11—C9	111.8 (3)
C5—C4—H4	120.6	C13—C11—H11	106.7
C6—C5—C4	122.0 (5)	C12—C11—H11	106.7
C6—C5—H5	119.0	C9—C11—H11	106.7
C4—C5—H5	119.0	C11—C12—H12A	109.5
C5—C6—C1	117.7 (4)	C11—C12—H12B	109.5
C5—C6—C8	116.0 (3)	H12A—C12—H12B	109.5
C1—C6—C8	126.2 (3)	C11—C12—H12C	109.5
O1—C7—H7A	109.5	H12A—C12—H12C	109.5
O1—C7—H7B	109.5	H12B—C12—H12C	109.5
H7A—C7—H7B	109.5	C11—C13—H13A	109.5
O1—C7—H7C	109.5	C11—C13—H13B	109.5
H7A—C7—H7C	109.5	H13A—C13—H13B	109.5
H7B—C7—H7C	109.5	C11—C13—H13C	109.5
O2—C8—N1	122.0 (3)	H13A—C13—H13C	109.5
O2—C8—C6	119.6 (3)	H13B—C13—H13C	109.5
C7—O1—C1—C2	13.4 (5)	C9—N1—C8—C6	179.2 (3)
C7—O1—C1—C6	−167.0 (4)	C5—C6—C8—O2	9.9 (5)
O1—C1—C2—C3	179.3 (3)	C1—C6—C8—O2	−171.7 (3)
C6—C1—C2—C3	−0.3 (6)	C5—C6—C8—N1	−169.6 (3)
C1—C2—C3—C4	−0.0 (6)	C1—C6—C8—N1	8.8 (5)
C2—C3—C4—C5	0.9 (7)	C8—N1—C9—C10	−130.9 (4)
C3—C4—C5—C6	−1.5 (7)	C8—N1—C9—C11	103.2 (4)
C4—C5—C6—C1	1.2 (6)	N1—C9—C10—O3	63.2 (4)
C4—C5—C6—C8	179.7 (4)	C11—C9—C10—O3	−172.2 (3)
O1—C1—C6—C5	−179.8 (3)	N1—C9—C11—C13	59.7 (4)
C2—C1—C6—C5	−0.2 (5)	C10—C9—C11—C13	−64.2 (5)
O1—C1—C6—C8	1.8 (5)	N1—C9—C11—C12	−66.1 (4)
C2—C1—C6—C8	−178.6 (3)	C10—C9—C11—C12	170.0 (3)
C9—N1—C8—O2	−0.3 (5)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O3—H3···O2^i	0.82	2.00	2.806 (4)	170
N1—H1N1···O1	0.86	1.96	2.656 (4)	137

Symmetry code: (i) x−1/2, −y+1/2, −z.