1-tert-Butyl 2-methyl 4-(R)-hydroxypyrrolidine-1,2-(2S)-dicarboxylate

The title compound, C₁₁H₁₉NO₅, is a protected derivative of trans-4-hydroxy-L-proline. The pyrrolidine ring has a twisted conformation. The N atom has planar coordination and is conjugated with the attached ester group. The methyl ester substituent is pseudo-equatorial, while the hydroxy group is pseudo-axial and acts as a hydrogen-bond donor to a carbonyl O atom in an adjacent mol­ecule, forming molecular chains.

Key indicators

• Single-crystal X-ray study
• T = 160 K
• Mean [sigma](C-C) = 0.002 Å
• R factor = 0.030
• wR factor = 0.075
• Data-to-parameter ratio = 11.2

checkCIF/PLATON results

No syntax errors found



Alert level C
PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given .......          ?

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           28.87
           From the CIF: _reflns_number_total               1786
           Count of symmetry unique reflns         1904
           Completeness (_total/calc)             93.80%
           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

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

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

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Computing details

Data collection: SMART (Bruker, 2001); cell refinement: local programs; data reduction: SAINT (Bruker, 2001); program(s) used to solve structure: SHELXTL (Sheldrick, 2001); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL and local programs.

1-tert-Butyl 2-methyl 4-(R)-hydroxypyrrolidine-1,2-(2S)-dicarboxylate

Crystal data

C11H19NO5	Dx = 1.293 Mg m^−3
Mr = 245.27	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, P212121	Cell parameters from 4967 reflections
a = 9.1813 (10) Å	θ = 2.7–28.9°
b = 10.7862 (12) Å	µ = 0.10 mm^−1
c = 12.7242 (14) Å	T = 160 K
V = 1260.1 (2) Å^3	Plate, colourless
Z = 4	0.53 × 0.24 × 0.09 mm
F(000) = 528

Data collection

Bruker SMART 1K CCD area-detector diffractometer	1486 reflections with I > 2σ(I)
Radiation source: sealed tube	Rint = 0.028
Graphite monochromator	θmax = 28.9°, θmin = 2.5°
Detector resolution: 8.192 pixels mm^-1	h = −11→12
thin–slice ω scans	k = −10→14
7889 measured reflections	l = −16→16
1786 independent 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)] = 0.030	H-atom parameters constrained
wR(F^2) = 0.075	w = 1/[σ^2(Fo^2) + (0.0493P)^2] where P = (Fo^2 + 2Fc^2)/3
S = 1.01	(Δ/σ)max < 0.001
1786 reflections	Δρmax = 0.20 e Å^−3
160 parameters	Δρmin = −0.14 e Å^−3
0 restraints	Extinction correction: SHELXTL (Sheldrick, 2001), Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.021 (3)

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

	x	y	z	Uiso*/Ueq
N1	0.70934 (13)	0.42434 (13)	0.55057 (10)	0.0226 (3)
C2	0.85332 (17)	0.41999 (15)	0.50152 (12)	0.0217 (3)
H2	0.9060	0.4994	0.5154	0.026*
C3	0.92829 (17)	0.31374 (15)	0.56131 (13)	0.0260 (4)
H3A	0.9083	0.2328	0.5276	0.031*
H3B	1.0349	0.3266	0.5648	0.031*
C4	0.85984 (18)	0.32068 (16)	0.67008 (12)	0.0266 (4)
H4	0.8718	0.2411	0.7095	0.032*
C5	0.69962 (17)	0.34752 (16)	0.64609 (13)	0.0241 (3)
H5A	0.6448	0.2701	0.6327	0.029*
H5B	0.6527	0.3934	0.7044	0.029*
C6	0.60692 (17)	0.50151 (15)	0.51369 (12)	0.0210 (3)
O1	0.62695 (12)	0.56988 (11)	0.43801 (9)	0.0263 (3)
O2	0.48411 (11)	0.49252 (10)	0.57003 (9)	0.0235 (3)
C7	0.35807 (17)	0.57536 (16)	0.54995 (13)	0.0264 (3)
C8	0.2575 (2)	0.5435 (2)	0.64053 (15)	0.0386 (5)
H8A	0.2330	0.4551	0.6378	0.058*
H8B	0.1681	0.5928	0.6351	0.058*
H8C	0.3063	0.5620	0.7072	0.058*
C9	0.28893 (19)	0.54084 (18)	0.44555 (14)	0.0336 (4)
H9A	0.3593	0.5542	0.3888	0.050*
H9B	0.2028	0.5926	0.4336	0.050*
H9C	0.2601	0.4534	0.4469	0.050*
C10	0.4041 (2)	0.71036 (17)	0.55570 (19)	0.0475 (6)
H10A	0.4578	0.7248	0.6211	0.071*
H10B	0.3175	0.7634	0.5541	0.071*
H10C	0.4667	0.7300	0.4956	0.071*
C11	0.85210 (18)	0.39420 (16)	0.38437 (13)	0.0244 (3)
O3	0.94519 (14)	0.43041 (14)	0.32595 (10)	0.0387 (3)
O4	0.74198 (13)	0.32101 (11)	0.35597 (9)	0.0302 (3)
C12	0.7372 (2)	0.2874 (2)	0.24574 (14)	0.0399 (5)
H12A	0.7288	0.3625	0.2029	0.060*
H12B	0.6528	0.2338	0.2329	0.060*
H12C	0.8266	0.2430	0.2269	0.060*
O5	0.92777 (14)	0.42095 (14)	0.72302 (9)	0.0363 (3)
H5	0.9024	0.4208	0.7865	0.055*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
N1	0.0206 (6)	0.0283 (7)	0.0189 (6)	0.0039 (6)	0.0035 (5)	0.0025 (6)
C2	0.0180 (7)	0.0253 (8)	0.0218 (7)	0.0008 (7)	0.0018 (6)	−0.0009 (7)
C3	0.0225 (7)	0.0297 (9)	0.0258 (8)	0.0043 (7)	−0.0012 (7)	0.0012 (7)
C4	0.0257 (8)	0.0311 (9)	0.0230 (8)	0.0018 (7)	−0.0009 (7)	0.0050 (7)
C5	0.0231 (7)	0.0270 (8)	0.0223 (8)	0.0009 (7)	0.0002 (6)	0.0051 (7)
C6	0.0210 (7)	0.0228 (7)	0.0191 (7)	−0.0017 (6)	−0.0013 (6)	−0.0038 (6)
O1	0.0259 (6)	0.0290 (6)	0.0240 (5)	−0.0006 (5)	−0.0005 (5)	0.0058 (5)
O2	0.0186 (5)	0.0284 (6)	0.0235 (6)	0.0041 (5)	0.0010 (5)	0.0028 (5)
C7	0.0185 (7)	0.0279 (8)	0.0329 (9)	0.0044 (7)	−0.0020 (7)	0.0003 (8)
C8	0.0262 (8)	0.0549 (12)	0.0345 (9)	0.0085 (9)	0.0029 (8)	−0.0035 (9)
C9	0.0276 (8)	0.0414 (10)	0.0317 (9)	0.0025 (8)	−0.0059 (7)	0.0048 (8)
C10	0.0331 (10)	0.0274 (10)	0.0821 (16)	0.0038 (8)	−0.0010 (11)	−0.0077 (11)
C11	0.0212 (8)	0.0264 (8)	0.0256 (8)	0.0021 (7)	0.0022 (6)	0.0030 (6)
O3	0.0313 (6)	0.0574 (9)	0.0272 (6)	−0.0105 (7)	0.0078 (5)	0.0027 (7)
O4	0.0330 (6)	0.0348 (7)	0.0229 (6)	−0.0073 (6)	0.0045 (5)	−0.0048 (5)
C12	0.0504 (11)	0.0454 (11)	0.0238 (9)	−0.0121 (10)	0.0041 (8)	−0.0096 (8)
O5	0.0312 (7)	0.0560 (9)	0.0218 (6)	−0.0069 (7)	−0.0012 (5)	−0.0039 (6)

Geometric parameters (Å, º)

N1—C2	1.463 (2)	C7—C9	1.519 (2)
N1—C5	1.4738 (19)	C7—C10	1.518 (3)
N1—C6	1.341 (2)	C8—H8A	0.980
C2—H2	1.000	C8—H8B	0.980
C2—C3	1.538 (2)	C8—H8C	0.980
C2—C11	1.516 (2)	C9—H9A	0.980
C3—H3A	0.990	C9—H9B	0.980
C3—H3B	0.990	C9—H9C	0.980
C3—C4	1.522 (2)	C10—H10A	0.980
C4—H4	1.000	C10—H10B	0.980
C4—C5	1.530 (2)	C10—H10C	0.980
C4—O5	1.419 (2)	C11—O3	1.198 (2)
C5—H5A	0.990	C11—O4	1.333 (2)
C5—H5B	0.990	O4—C12	1.450 (2)
C6—O1	1.2267 (19)	C12—H12A	0.980
C6—O2	1.3397 (19)	C12—H12B	0.980
O2—C7	1.4842 (19)	C12—H12C	0.980
C7—C8	1.516 (2)	O5—H5	0.840
C2—N1—C5	112.86 (12)	O2—C7—C10	110.62 (13)
C2—N1—C6	120.30 (13)	C8—C7—C9	110.77 (15)
C5—N1—C6	126.54 (13)	C8—C7—C10	110.51 (16)
N1—C2—H2	109.5	C9—C7—C10	113.19 (16)
N1—C2—C3	102.55 (12)	C7—C8—H8A	109.5
N1—C2—C11	114.75 (13)	C7—C8—H8B	109.5
H2—C2—C3	109.5	C7—C8—H8C	109.5
H2—C2—C11	109.5	H8A—C8—H8B	109.5
C3—C2—C11	110.66 (13)	H8A—C8—H8C	109.5
C2—C3—H3A	111.1	H8B—C8—H8C	109.5
C2—C3—H3B	111.1	C7—C9—H9A	109.5
C2—C3—C4	103.20 (13)	C7—C9—H9B	109.5
H3A—C3—H3B	109.1	C7—C9—H9C	109.5
H3A—C3—C4	111.1	H9A—C9—H9B	109.5
H3B—C3—C4	111.1	H9A—C9—H9C	109.5
C3—C4—H4	111.6	H9B—C9—H9C	109.5
C3—C4—C5	103.00 (13)	C7—C10—H10A	109.5
C3—C4—O5	106.72 (13)	C7—C10—H10B	109.5
H4—C4—C5	111.6	C7—C10—H10C	109.5
H4—C4—O5	111.6	H10A—C10—H10B	109.5
C5—C4—O5	111.91 (15)	H10A—C10—H10C	109.5
N1—C5—C4	102.28 (13)	H10B—C10—H10C	109.5
N1—C5—H5A	111.3	C2—C11—O3	123.01 (16)
N1—C5—H5B	111.3	C2—C11—O4	112.39 (14)
C4—C5—H5A	111.3	O3—C11—O4	124.47 (15)
C4—C5—H5B	111.3	C11—O4—C12	115.72 (13)
H5A—C5—H5B	109.2	O4—C12—H12A	109.5
N1—C6—O1	122.88 (14)	O4—C12—H12B	109.5
N1—C6—O2	110.98 (13)	O4—C12—H12C	109.5
O1—C6—O2	126.14 (15)	H12A—C12—H12B	109.5
C6—O2—C7	121.37 (12)	H12A—C12—H12C	109.5
O2—C7—C8	101.97 (13)	H12B—C12—H12C	109.5
O2—C7—C9	109.20 (13)	C4—O5—H5	109.5
C5—N1—C2—C3	10.55 (17)	C5—N1—C6—O1	174.16 (15)
C5—N1—C2—C11	130.59 (14)	C5—N1—C6—O2	−5.9 (2)
C6—N1—C2—C3	−175.32 (14)	N1—C6—O2—C7	175.30 (13)
C6—N1—C2—C11	−55.3 (2)	O1—C6—O2—C7	−4.8 (2)
N1—C2—C3—C4	−31.25 (15)	C6—O2—C7—C8	−172.30 (14)
C11—C2—C3—C4	−154.08 (14)	C6—O2—C7—C9	70.46 (18)
C2—C3—C4—C5	40.51 (16)	C6—O2—C7—C10	−54.8 (2)
C2—C3—C4—O5	−77.48 (15)	N1—C2—C11—O3	151.76 (17)
C2—N1—C5—C4	14.25 (18)	N1—C2—C11—O4	−32.2 (2)
C6—N1—C5—C4	−159.43 (15)	C3—C2—C11—O3	−92.81 (19)
C3—C4—C5—N1	−33.36 (16)	C3—C2—C11—O4	83.22 (17)
O5—C4—C5—N1	80.92 (16)	C2—C11—O4—C12	−177.28 (15)
C2—N1—C6—O1	0.9 (2)	O3—C11—O4—C12	−1.3 (2)
C2—N1—C6—O2	−179.20 (13)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5···O1^i	0.84	1.95	2.7831 (16)	171

Symmetry code: (i) −x+3/2, −y+1, z+1/2.