rac-Ethyl rel-(2R,3R,4S)-4-hy­droxy-1,2-dimethyl-5-oxopyrrolidine-3-carboxyl­ate

The asymmetric unit of the title compound, C₉H₁₅NO₄, consists of a functionalized pyrrolidine ring having an envelope conformation, synthesized as an ethyl ester. The mol­ecule has three chiral centres and crystallized as a racemic mixture. In the crystal, mol­ecules are linked by pairwise O—H...O bonds, generating dimers with twofold rotational symmetry.

Key indicators

Structure: I

• Single-crystal X-ray study
• T = 173 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.033
• wR factor = 0.088
• Data-to-parameter ratio = 14.0

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT911_ALERT_3_C Missing FCF Refl Between Thmin & STh/L=    0.600         17 Report
PLAT913_ALERT_3_C Missing # of Very Strong Reflections in FCF ....          7 Note

Alert level G
PLAT002_ALERT_2_G Number of Distance or Angle Restraints on AtSite          2 Note
PLAT172_ALERT_4_G The CIF-Embedded .res File Contains DFIX Records          1 Report
PLAT480_ALERT_4_G Long H...A H-Bond Reported H1       ..O1       .       2.62 Ang.
PLAT793_ALERT_4_G Model has Chirality at C1          (Centro SPGR)          R Verify
PLAT793_ALERT_4_G Model has Chirality at C3          (Centro SPGR)          S Verify
PLAT793_ALERT_4_G Model has Chirality at C4          (Centro SPGR)          R Verify
PLAT860_ALERT_3_G Number of Least-Squares Restraints .............          1 Note
PLAT912_ALERT_4_G Missing # of FCF Reflections Above STh/L=  0.600          3 Note
PLAT933_ALERT_2_G Number of HKL-OMIT Records in Embedded .res File          3 Note
PLAT978_ALERT_2_G Number C-C Bonds with Positive Residual Density.          3 Info

   0 ALERT level A = Most likely a serious problem - resolve or explain
   0 ALERT level B = A potentially serious problem, consider carefully
   2 ALERT level C = Check. Ensure it is not caused by an omission or oversight
  10 ALERT level G = General information/check it is not something unexpected

   0 ALERT type 1 CIF construction/syntax error, inconsistent or missing data
   3 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
   6 ALERT type 4 Improvement, methodology, query or suggestion
   0 ALERT type 5 Informative message, check

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Computing details

Data collection: CrystalClear-SM Expert (Rigaku, 2015); cell refinement: CrystalClear-SM Expert (Rigaku, 2015); data reduction: CrystalClear-SM Expert (Rigaku, 2015); program(s) used to solve structure: SHELXT2018/2 (Sheldrick, 2015a); program(s) used to refine structure: SHELXL2018/3 (Sheldrick, 2015b); molecular graphics: Olex2 (Dolomanov et al., 2009); software used to prepare material for publication: Olex2 (Dolomanov et al., 2009).

rac-Ethyl rel-(2R,3R,4S)-4-hydroxy-1,2-dimethyl-5-oxopyrrolidine-3-carboxylate

Crystal data

C9H15NO4	F(000) = 864
Mr = 201.22	Dx = 1.291 Mg m^−3
Monoclinic, C2/c	Mo Kα radiation, λ = 0.71075 Å
a = 12.1599 (15) Å	Cell parameters from 3484 reflections
b = 8.6065 (8) Å	θ = 2.1–27.5°
c = 20.217 (2) Å	µ = 0.10 mm^−1
β = 101.960 (3)°	T = 173 K
V = 2069.9 (4) Å^3	Prism, colorless
Z = 8	0.2 × 0.2 × 0.1 mm

Data collection

Rigaku XtaLAB P200 diffractometer	1769 reflections with I > 2σ(I)
Detector resolution: 5.814 pixels mm^-1	Rint = 0.019
ω scans	θmax = 25.4°, θmin = 2.1°
Absorption correction: multi-scan (REQAB; Rigaku, 1998)	h = −14→14
Tmin = 0.879, Tmax = 0.990	k = −10→10
11140 measured reflections	l = −24→24
1874 independent reflections

Refinement

Refinement on F^2	Primary atom site location: dual
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F^2 > 2σ(F^2)] = 0.033	Hydrogen site location: mixed
wR(F^2) = 0.088	H atoms treated by a mixture of independent and constrained refinement
S = 1.04	w = 1/[σ^2(Fo^2) + (0.0452P)^2 + 1.1669P] where P = (Fo^2 + 2Fc^2)/3
1874 reflections	(Δ/σ)max < 0.001
134 parameters	Δρmax = 0.24 e Å^−3
1 restraint	Δρmin = −0.18 e Å^−3

Special details

Refinement. The hydroxyl H atom (H2) was refined with free coordinates and isotropic displacement parameter.

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

	x	y	z	Uiso*/Ueq
O1	0.65691 (7)	0.16087 (10)	0.24315 (4)	0.0360 (2)
O2	0.53577 (7)	0.18679 (11)	0.35435 (4)	0.0388 (2)
O3	0.58426 (9)	0.59491 (13)	0.40623 (5)	0.0556 (3)
O4	0.68278 (7)	0.49308 (10)	0.50163 (4)	0.0348 (2)
N1	0.78865 (8)	0.29976 (11)	0.31723 (5)	0.0282 (2)
C2	0.68560 (9)	0.24451 (13)	0.29333 (5)	0.0275 (3)
C3	0.60731 (9)	0.30292 (13)	0.33799 (5)	0.0278 (3)
H3	0.561557	0.391982	0.315420	0.033*
C4	0.68834 (9)	0.35965 (13)	0.40091 (5)	0.0259 (3)
H4	0.706096	0.271938	0.433837	0.031*
C1	0.79582 (9)	0.40440 (13)	0.37550 (5)	0.0275 (3)
H1	0.789576	0.514521	0.359380	0.033*
C9	0.88156 (10)	0.28015 (15)	0.28261 (6)	0.0359 (3)
H9A	0.902826	0.381524	0.267070	0.043*
H9B	0.858357	0.211119	0.243670	0.043*
H9C	0.946000	0.234634	0.313807	0.043*
C5	0.64421 (9)	0.49526 (13)	0.43501 (6)	0.0294 (3)
C6	0.64892 (11)	0.62159 (15)	0.54030 (6)	0.0364 (3)
H6A	0.566573	0.619870	0.537083	0.044*
H6B	0.669524	0.722225	0.522480	0.044*
C7	0.70872 (15)	0.60126 (19)	0.61170 (7)	0.0567 (4)
H7A	0.790035	0.600863	0.614059	0.068*
H7B	0.686220	0.502495	0.629065	0.068*
H7C	0.689349	0.687011	0.639073	0.068*
C8	0.90310 (10)	0.38489 (16)	0.42851 (6)	0.0374 (3)
H8A	0.967321	0.419643	0.410005	0.045*
H8B	0.912839	0.275194	0.441383	0.045*
H8C	0.898462	0.447241	0.468402	0.045*
H2	0.4729 (10)	0.174 (2)	0.3162 (6)	0.063 (5)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0353 (5)	0.0407 (5)	0.0292 (4)	0.0041 (4)	0.0005 (3)	−0.0061 (4)
O2	0.0307 (4)	0.0512 (5)	0.0333 (5)	−0.0129 (4)	0.0038 (4)	0.0043 (4)
O3	0.0666 (7)	0.0579 (7)	0.0377 (5)	0.0363 (5)	0.0007 (5)	−0.0005 (4)
O4	0.0418 (5)	0.0345 (5)	0.0271 (4)	0.0084 (4)	0.0048 (3)	−0.0033 (3)
N1	0.0256 (5)	0.0321 (5)	0.0274 (5)	0.0024 (4)	0.0067 (4)	0.0004 (4)
C2	0.0280 (5)	0.0283 (6)	0.0247 (5)	0.0033 (4)	0.0022 (4)	0.0041 (4)
C3	0.0239 (5)	0.0324 (6)	0.0262 (6)	0.0001 (4)	0.0031 (4)	0.0030 (4)
C4	0.0238 (5)	0.0286 (6)	0.0247 (5)	0.0024 (4)	0.0034 (4)	0.0025 (4)
C1	0.0257 (5)	0.0273 (5)	0.0296 (6)	0.0003 (4)	0.0061 (4)	−0.0003 (4)
C9	0.0297 (6)	0.0449 (7)	0.0353 (6)	0.0061 (5)	0.0118 (5)	0.0014 (5)
C5	0.0248 (5)	0.0342 (6)	0.0291 (6)	0.0029 (5)	0.0054 (4)	0.0014 (5)
C6	0.0399 (7)	0.0341 (6)	0.0370 (7)	0.0036 (5)	0.0126 (5)	−0.0060 (5)
C7	0.0757 (10)	0.0528 (9)	0.0374 (7)	0.0168 (8)	0.0023 (7)	−0.0136 (6)
C8	0.0252 (6)	0.0478 (7)	0.0372 (6)	−0.0010 (5)	0.0021 (5)	−0.0065 (5)

Geometric parameters (Å, º)

O1—C2	1.2340 (14)	C1—H1	1.0000
O2—C3	1.4087 (14)	C1—C8	1.5162 (16)
O2—H2	0.973 (5)	C9—H9A	0.9800
O3—C5	1.1957 (14)	C9—H9B	0.9800
O4—C5	1.3313 (14)	C9—H9C	0.9800
O4—C6	1.4620 (14)	C6—H6A	0.9900
N1—C2	1.3337 (15)	C6—H6B	0.9900
N1—C1	1.4709 (14)	C6—C7	1.4860 (19)
N1—C9	1.4569 (14)	C7—H7A	0.9800
C2—C3	1.5266 (15)	C7—H7B	0.9800
C3—H3	1.0000	C7—H7C	0.9800
C3—C4	1.5192 (15)	C8—H8A	0.9800
C4—H4	1.0000	C8—H8B	0.9800
C4—C1	1.5488 (14)	C8—H8C	0.9800
C4—C5	1.5095 (15)
C3—O2—H2	108.5 (10)	N1—C9—H9B	109.5
C5—O4—C6	116.81 (9)	N1—C9—H9C	109.5
C2—N1—C1	113.81 (9)	H9A—C9—H9B	109.5
C2—N1—C9	123.27 (10)	H9A—C9—H9C	109.5
C9—N1—C1	122.17 (9)	H9B—C9—H9C	109.5
O1—C2—N1	126.17 (10)	O3—C5—O4	123.63 (11)
O1—C2—C3	125.01 (10)	O3—C5—C4	124.81 (10)
N1—C2—C3	108.82 (9)	O4—C5—C4	111.53 (9)
O2—C3—C2	113.35 (10)	O4—C6—H6A	110.3
O2—C3—H3	109.8	O4—C6—H6B	110.3
O2—C3—C4	110.88 (9)	O4—C6—C7	107.16 (10)
C2—C3—H3	109.8	H6A—C6—H6B	108.5
C4—C3—C2	103.02 (8)	C7—C6—H6A	110.3
C4—C3—H3	109.8	C7—C6—H6B	110.3
C3—C4—H4	109.1	C6—C7—H7A	109.5
C3—C4—C1	104.33 (8)	C6—C7—H7B	109.5
C1—C4—H4	109.1	C6—C7—H7C	109.5
C5—C4—C3	113.62 (9)	H7A—C7—H7B	109.5
C5—C4—H4	109.1	H7A—C7—H7C	109.5
C5—C4—C1	111.32 (9)	H7B—C7—H7C	109.5
N1—C1—C4	101.50 (8)	C1—C8—H8A	109.5
N1—C1—H1	109.4	C1—C8—H8B	109.5
N1—C1—C8	113.44 (9)	C1—C8—H8C	109.5
C4—C1—H1	109.4	H8A—C8—H8B	109.5
C8—C1—C4	113.55 (9)	H8A—C8—H8C	109.5
C8—C1—H1	109.4	H8B—C8—H8C	109.5
N1—C9—H9A	109.5
O1—C2—C3—O2	45.04 (15)	C1—N1—C2—O1	176.42 (11)
O1—C2—C3—C4	164.92 (11)	C1—N1—C2—C3	−3.06 (12)
O2—C3—C4—C1	148.36 (9)	C1—C4—C5—O3	84.29 (14)
O2—C3—C4—C5	−90.22 (11)	C1—C4—C5—O4	−94.04 (11)
N1—C2—C3—O2	−135.48 (10)	C9—N1—C2—O1	6.15 (18)
N1—C2—C3—C4	−15.60 (12)	C9—N1—C2—C3	−173.33 (10)
C2—N1—C1—C4	19.89 (12)	C9—N1—C1—C4	−169.72 (9)
C2—N1—C1—C8	142.07 (10)	C9—N1—C1—C8	−47.54 (14)
C2—C3—C4—C1	26.79 (11)	C5—O4—C6—C7	−175.57 (11)
C2—C3—C4—C5	148.21 (9)	C5—C4—C1—N1	−151.06 (9)
C3—C4—C1—N1	−28.13 (10)	C5—C4—C1—C8	86.83 (11)
C3—C4—C1—C8	−150.24 (10)	C6—O4—C5—O3	−0.29 (17)
C3—C4—C5—O3	−33.14 (16)	C6—O4—C5—C4	178.06 (9)
C3—C4—C5—O4	148.53 (9)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O2—H2···O1^i	0.97 (1)	1.78 (1)	2.7405 (12)	170 (2)
C1—H1···O1^ii	1.00	2.62	3.3953 (14)	134
C9—H9A···O1^ii	0.98	2.51	3.3355 (16)	142
C9—H9C···O3^iii	0.98	2.54	3.5086 (15)	169
C7—H7C···O1^iv	0.98	2.58	3.5134 (17)	160

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