4(R)-(N-Benzoylamino)-5(R)-methyltetra­hydrofuran-2-one: an L-β-threonine analogue

The title compound, C₁₂H₁₃NO₃, was synthesized from L-β-threonine, and the lactone ring was formed by nucleophilic reaction of the β-hydroxyl group in the presence of a base. The methyl and amino groups are located at cis positions, but the puckering of the lactone ring reduces their steric hindrance. The benzoyl π-electrons and amide bond were expected to conjugate to each other, but their least-square planes are inclined at 26.3 (1)°. The hydrogen bonds between the amide bonds extend along the b axis and stabilize the molecular packing.

Key indicators

• Single-crystal X-ray study
• T = 120 K
• Mean [sigma](C-C) = 0.004 Å
• R factor = 0.043
• wR factor = 0.117
• Data-to-parameter ratio = 9.5

checkCIF/PLATON results

No syntax errors found



Alert level A
PLAT029_ALERT_3_A _diffrn_measured_fraction_theta_full Low .......       0.98

Alert level C
ABSTM02_ALERT_3_C  The ratio of expected to reported Tmax/Tmin(RR') is < 0.90
            Tmin and Tmax reported:      0.843     0.997
            Tmin' and Tmax expected:      0.952     0.997
            RR' =      0.886
            Please check that your absorption correction is appropriate.
STRVA01_ALERT_4_C           Flack test results are meaningless.
           From the CIF: _refine_ls_abs_structure_Flack    0.100
           From the CIF: _refine_ls_abs_structure_Flack_su    1.600
PLAT032_ALERT_4_C Std Uncertainty in Flack Parameter too High ....       1.60
PLAT048_ALERT_1_C MoietyFormula Not Given ........................          ?
PLAT061_ALERT_3_C Tmax/Tmin Range Test RR' too Large .............       0.89
PLAT094_ALERT_2_C Ratio of Maximum / Minimum Residual Density ....       2.61
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?
PLAT152_ALERT_1_C Supplied and Calc Volume s.u. Inconsistent .....          ?

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           27.86
           From the CIF: _reflns_number_total               1385
           Count of symmetry unique reflns         1418
           Completeness (_total/calc)             97.67%
           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

   1 ALERT level A = In general: serious problem
   0 ALERT level B = Potentially serious problem
   8 ALERT level C = Check and explain
   1 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
   3 ALERT type 3 Indicator that the structure quality may be low
   4 ALERT type 4 Improvement, methodology, query or suggestion

---

Computing details

Data collection: SMART (Bruker, 1998); cell refinement: SMART (Bruker, 1998); data reduction: SAINT-Plus (Bruker, 1998); program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: PLATON (Spek, 2001); software used to prepare material for publication: PARST (Nardelli, 1983).

L-β-threonine lactone analogue

Crystal data

C12H13NO3	F(000) = 232
Mr = 219.23	Dx = 1.364 Mg m^−3
Monoclinic, P21	Mo Kα radiation, λ = 0.71073 Å
a = 8.521 (1) Å	Cell parameters from 2050 reflections
b = 5.1143 (6) Å	θ = 2.4–28.3°
c = 12.401 (2) Å	µ = 0.10 mm^−1
β = 99.098 (2)°	T = 120 K
V = 533.6 (1) Å^3	Needle, colourless
Z = 2	0.50 × 0.06 × 0.03 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer	1385 independent reflections
Radiation source: MacScience, M18XCE rotating anode	1339 reflections with I > 2σ(I)
Graphite monochromator	Rint = 0.024
Detector resolution: 8.366 pixels mm^-1	θmax = 27.9°, θmin = 1.7°
ω–scan	h = −10→10
Absorption correction: multi-scan (SADABS; Sheldrick, 1996)	k = −6→6
Tmin = 0.843, Tmax = 0.997	l = −16→16
4798 measured reflections

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)] = 0.043	H-atom parameters constrained
wR(F^2) = 0.118	w = 1/[σ^2(Fo^2) + (0.0819P)^2 + 0.0481P] where P = (Fo^2 + 2Fc^2)/3
S = 1.12	(Δ/σ)max < 0.001
1385 reflections	Δρmax = 0.40 e Å^−3
146 parameters	Δρmin = −0.16 e Å^−3
1 restraint	Absolute structure: (Flack, 1983)
Primary atom site location: structure-invariant direct methods	Absolute structure parameter: 0.1 (16)

Special details

Geometry. Least-squares planes (x,y,z in crystal coordinates) and deviations from them (* indicates atom used to define plane)

6.4095 (0.0066) x - 2.9265 (0.0048) y + 2.5256 (0.0123) z = 2.7150 (0.0066)

* 0.0054 (0.0017) C11 * -0.0075 (0.0018) C12 * 0.0032 (0.0018) C13 * 0.0033 (0.0019) C14 * -0.0054 (0.0021) C15 * 0.0011 (0.0019) C16

Rms deviation of fitted atoms = 0.0048

7.9709 (0.0023) x - 0.7992 (0.0054) y + 2.0477 (0.0098) z = 2.9788 (0.0029)

Angle to previous plane (with approximate e.s.d.) = 26.28 (0.11)

* 0.0075 (0.0010) C11 * -0.0023 (0.0018) C17 * -0.0025 (0.0007) O17 * -0.0127 (0.0014) N1 * 0.0100 (0.0010) C1A

Rms deviation of fitted atoms = 0.0081

5.7289 (0.0073) x - 3.6501 (0.0042) y - 3.7238 (0.0127) z = 0.5615 (0.0033)

Angle to previous plane (with approximate e.s.d.) = 47.30 (0.09)

* 0.1757 (0.0014) C1A * -0.1476 (0.0013) C2B * 0.0615 (0.0014) O3G * 0.0539 (0.0014) C5 * -0.1436 (0.0014) C4B 0.1712 (0.0035) O5 - 1.5442 (0.0034) C3G

Rms deviation of fitted atoms = 0.1265

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
C11	0.2577 (2)	0.0418 (5)	0.47163 (17)	0.0178 (4)
C12	0.3287 (3)	0.2528 (6)	0.53074 (18)	0.0243 (5)
H1	0.3930	0.3708	0.4978	0.029*
C13	0.3057 (3)	0.2915 (6)	0.63838 (19)	0.0307 (6)
H2	0.3558	0.4341	0.6793	0.037*
C14	0.2099 (3)	0.1224 (6)	0.68542 (18)	0.0321 (6)
H3	0.1941	0.1490	0.7588	0.039*
C15	0.1367 (4)	−0.0862 (6)	0.6262 (2)	0.0371 (7)
H4	0.0699	−0.2008	0.6587	0.045*
C16	0.1609 (3)	−0.1277 (5)	0.5190 (2)	0.0294 (5)
H5	0.1115	−0.2714	0.4785	0.035*
C17	0.2804 (2)	−0.0139 (4)	0.35645 (16)	0.0164 (4)
O17	0.2676 (2)	−0.2382 (3)	0.31889 (13)	0.0225 (4)
N1	0.3150 (2)	0.1897 (4)	0.29617 (14)	0.0167 (4)
H6	0.3212	0.3484	0.3239	0.020*
C1A	0.3422 (2)	0.1467 (4)	0.18473 (15)	0.0154 (4)
H7	0.4202	0.0006	0.1846	0.018*
C2B	0.1896 (3)	0.0788 (5)	0.10329 (16)	0.0199 (5)
H8	0.1774	−0.1155	0.0984	0.024*
O3G	0.22233 (18)	0.1791 (4)	−0.00082 (11)	0.0237 (4)
C3G	0.0385 (3)	0.1974 (6)	0.12968 (19)	0.0277 (5)
H9	0.0560	0.3830	0.1472	0.042*
H10	0.0070	0.1066	0.1925	0.042*
H11	−0.0458	0.1797	0.0665	0.042*
C4B	0.4059 (3)	0.3862 (5)	0.13356 (16)	0.0189 (4)
H12	0.3660	0.5491	0.1628	0.023*
H13	0.5235	0.3886	0.1467	0.023*
C5	0.3422 (3)	0.3549 (5)	0.01343 (18)	0.0211 (5)
O5	0.3829 (2)	0.4643 (4)	−0.06277 (13)	0.0318 (4)

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
C11	0.0199 (9)	0.0187 (10)	0.0153 (9)	0.0042 (8)	0.0047 (7)	0.0007 (8)
C12	0.0243 (10)	0.0306 (12)	0.0183 (9)	−0.0030 (10)	0.0041 (8)	−0.0040 (10)
C13	0.0308 (11)	0.0418 (16)	0.0185 (10)	0.0030 (11)	0.0003 (9)	−0.0084 (11)
C14	0.0366 (13)	0.0460 (17)	0.0146 (10)	0.0104 (12)	0.0068 (9)	0.0005 (11)
C15	0.0511 (16)	0.0389 (16)	0.0264 (12)	−0.0038 (13)	0.0216 (11)	0.0046 (12)
C16	0.0397 (13)	0.0259 (12)	0.0250 (11)	−0.0045 (12)	0.0129 (10)	−0.0002 (11)
C17	0.0180 (9)	0.0156 (10)	0.0165 (9)	0.0005 (8)	0.0053 (7)	−0.0009 (8)
O17	0.0337 (8)	0.0147 (7)	0.0211 (8)	−0.0003 (7)	0.0103 (6)	−0.0019 (7)
N1	0.0260 (8)	0.0117 (8)	0.0136 (8)	0.0002 (7)	0.0065 (6)	−0.0018 (6)
C1A	0.0225 (10)	0.0119 (9)	0.0130 (8)	−0.0010 (8)	0.0070 (7)	−0.0023 (8)
C2B	0.0265 (11)	0.0190 (10)	0.0148 (9)	−0.0063 (9)	0.0056 (8)	−0.0001 (8)
O3G	0.0297 (8)	0.0285 (9)	0.0139 (7)	−0.0050 (8)	0.0064 (6)	0.0013 (7)
C3G	0.0218 (10)	0.0373 (14)	0.0247 (10)	−0.0011 (11)	0.0056 (8)	0.0046 (11)
C4B	0.0268 (10)	0.0140 (9)	0.0174 (9)	−0.0018 (8)	0.0083 (8)	−0.0013 (8)
C5	0.0257 (10)	0.0216 (10)	0.0180 (9)	0.0018 (9)	0.0097 (8)	0.0016 (8)
O5	0.0414 (10)	0.0354 (11)	0.0213 (8)	−0.0047 (8)	0.0136 (7)	0.0064 (8)

Geometric parameters (Å, º)

C11—C12	1.388 (3)	N1—H6	0.8800
C11—C16	1.389 (3)	C1A—C4B	1.519 (3)
C11—C17	1.499 (3)	C1A—C2B	1.554 (3)
C12—C13	1.394 (3)	C1A—H7	1.0000
C12—H1	0.9500	C2B—O3G	1.457 (2)
C13—C14	1.380 (4)	C2B—C3G	1.505 (3)
C13—H2	0.9500	C2B—H8	1.0000
C14—C15	1.386 (4)	O3G—C5	1.351 (3)
C14—H3	0.9500	C3G—H9	0.9800
C15—C16	1.393 (3)	C3G—H10	0.9800
C15—H4	0.9500	C3G—H11	0.9800
C16—H5	0.9500	C4B—C5	1.511 (3)
C17—O17	1.236 (3)	C4B—H12	0.9900
C17—N1	1.342 (3)	C4B—H13	0.9900
N1—C1A	1.454 (2)	C5—O5	1.196 (3)
C12—C11—C16	120.0 (2)	C4B—C1A—C2B	103.1 (2)
C12—C11—C17	122.7 (2)	N1—C1A—H7	108.7
C16—C11—C17	117.4 (2)	C4B—C1A—H7	108.7
C11—C12—C13	120.0 (2)	C2B—C1A—H7	108.7
C11—C12—H1	120.0	O3G—C2B—C3G	109.9 (2)
C13—C12—H1	120.0	O3G—C2B—C1A	103.9 (2)
C14—C13—C12	119.9 (2)	C3G—C2B—C1A	115.2 (2)
C14—C13—H2	120.1	O3G—C2B—H8	109.2
C12—C13—H2	120.1	C3G—C2B—H8	109.2
C13—C14—C15	120.3 (2)	C1A—C2B—H8	109.2
C13—C14—H3	119.8	C5—O3G—C2B	111.4 (2)
C15—C14—H3	119.8	C2B—C3G—H9	109.5
C14—C15—C16	120.0 (2)	C2B—C3G—H10	109.5
C14—C15—H4	120.0	H9—C3G—H10	109.5
C16—C15—H4	120.0	C2B—C3G—H11	109.5
C11—C16—C15	119.7 (2)	H9—C3G—H11	109.5
C11—C16—H5	120.1	H10—C3G—H11	109.5
C15—C16—H5	120.1	C5—C4B—C1A	103.3 (2)
O17—C17—N1	121.6 (2)	C5—C4B—H12	111.1
O17—C17—C11	121.2 (2)	C1A—C4B—H12	111.1
N1—C17—C11	117.2 (2)	C5—C4B—H13	111.1
C17—N1—C1A	119.6 (2)	C1A—C4B—H13	111.1
C17—N1—H6	120.2	H12—C4B—H13	109.1
C1A—N1—H6	120.2	O5—C5—O3G	121.0 (2)
N1—C1A—C4B	113.3 (2)	O5—C5—C4B	128.8 (2)
N1—C1A—C2B	114.1 (2)	O3G—C5—C4B	110.2 (2)
C16—C11—C12—C13	1.3 (4)	C17—N1—C1A—C4B	−170.66 (18)
C17—C11—C12—C13	−178.7 (2)	C17—N1—C1A—C2B	71.8 (2)
C11—C12—C13—C14	−1.1 (4)	N1—C1A—C2B—O3G	150.75 (17)
C12—C13—C14—C15	0.1 (4)	C4B—C1A—C2B—O3G	27.4 (2)
C13—C14—C15—C16	0.7 (4)	N1—C1A—C2B—C3G	30.5 (3)
C12—C11—C16—C15	−0.5 (4)	C4B—C1A—C2B—C3G	−92.9 (2)
C17—C11—C16—C15	179.5 (2)	C3G—C2B—O3G—C5	105.5 (2)
C14—C15—C16—C11	−0.5 (4)	C1A—C2B—O3G—C5	−18.2 (2)
C12—C11—C17—O17	153.7 (2)	N1—C1A—C4B—C5	−150.28 (18)
C16—C11—C17—O17	−26.3 (3)	C2B—C1A—C4B—C5	−26.4 (2)
C12—C11—C17—N1	−26.4 (3)	C2B—O3G—C5—O5	−177.8 (2)
C16—C11—C17—N1	153.6 (2)	C2B—O3G—C5—C4B	1.1 (3)
O17—C17—N1—C1A	−1.6 (3)	C1A—C4B—C5—O5	−164.4 (2)
C11—C17—N1—C1A	178.53 (18)	C1A—C4B—C5—O3G	16.9 (2)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H6···O17^i	0.88	2.16	2.973 (3)	153

Symmetry code: (i) x, y+1, z.