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organic compounds
W. Clegg and L. Horsburgh
The title compound, C22H24INO4, is a chiral reagent developed and used for the synthesis of unnatural amino acids. It forms chains in its crystal structure, via weak N—HO=C hydrogen bonds. The bulky iodo substituent lies gauche to the two substituents on the neighbouring C atom, about a C—C single bond, rather than gauche to one and trans to the other. This does not seem to be a consequence of any significant intermolecular interactions. The absolute configuration has been confirmed by this experiment and is as expected from the synthesis.
Supporting information
Crystallographic Information File (CIF) https://doi.org/10.1107/S1600536803025467/bt6377sup1.cif | |
Structure factor file (CIF format) https://doi.org/10.1107/S1600536803025467/bt6377Isup2.hkl |
CCDC reference: 227882
Key indicators
- Single-crystal X-ray study
- T = 160 K
- Mean (C-C) = 0.003 Å
- R factor = 0.026
- wR factor = 0.051
- Data-to-parameter ratio = 20.0
checkCIF/PLATON results
No syntax errors found
Alert level C PLAT125_ALERT_4_C No _symmetry_space_group_name_Hall Given ....... ? PLAT230_ALERT_2_C Hirshfeld Test Diff for O1 - C3 = 5.40 su PLAT230_ALERT_2_C Hirshfeld Test Diff for O3 - C8 = 5.26 su PLAT230_ALERT_2_C Hirshfeld Test Diff for N1 - C8 = 5.20 su
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 28.66 From the CIF: _reflns_number_total 5121 Count of symmetry unique reflns 3152 Completeness (_total/calc) 162.47% TEST3: Check Friedels for noncentro structure Estimate of Friedel pairs measured 1969 Fraction of Friedel pairs measured 0.625 Are heavy atom types Z>Si present yes
0 ALERT level A = In general: serious problem 0 ALERT level B = Potentially serious problem 4 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 3 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
Computing details top
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.
tert-Butyl
(2R)-2-(9H-Fluoren-9-ylmethoxycarbonylamino)-3-iodopropionate top
Crystal data top
C22H24INO4 | Dx = 1.515 Mg m−3 |
Mr = 493.32 | Mo Kα radiation, λ = 0.71073 Å |
Orthorhombic, P212121 | Cell parameters from 9823 reflections |
a = 9.2875 (7) Å | θ = 2.4–28.6° |
b = 12.3181 (9) Å | µ = 1.51 mm−1 |
c = 18.9028 (13) Å | T = 160 K |
V = 2162.6 (3) Å3 | Block, colourless |
Z = 4 | 0.49 × 0.16 × 0.12 mm |
F(000) = 992 |
Data collection top
Bruker SMART 1K CCD diffractometer | 5121 independent reflections |
Radiation source: sealed tube | 4536 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.029 |
Detector resolution: 8.192 pixels mm-1 | θmax = 28.7°, θmin = 2.0° |
thin–slice ω scans | h = −11→12 |
Absorption correction: multi-scan (SADABS; Sheldrick, 2002) | k = −15→14 |
Tmin = 0.667, Tmax = 0.835 | l = −17→25 |
13825 measured reflections |
Refinement top
Refinement on F2 | Secondary atom site location: difference Fourier map |
Least-squares matrix: full | Hydrogen site location: inferred from neighbouring sites |
R[F2 > 2σ(F2)] = 0.026 | H-atom parameters constrained |
wR(F2) = 0.051 | w = 1/[σ2(Fo2) + (0.0241P)2] where P = (Fo2 + 2Fc2)/3 |
S = 0.98 | (Δ/σ)max = 0.002 |
5121 reflections | Δρmax = 0.53 e Å−3 |
256 parameters | Δρmin = −0.48 e Å−3 |
0 restraints | Absolute structure: Flack (1983), 2159 Friedel pairs |
Primary atom site location: structure-invariant direct methods | Absolute structure parameter: −0.027 (12) |
Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2) top
x | y | z | Uiso*/Ueq | ||
I1 | 0.828574 (19) | −0.054789 (14) | 0.548113 (9) | 0.03339 (5) | |
C1 | 0.6013 (3) | −0.02090 (19) | 0.55378 (14) | 0.0259 (5) | |
H1A | 0.5596 | −0.0241 | 0.5056 | 0.031* | |
H1B | 0.5536 | −0.0773 | 0.5829 | 0.031* | |
C2 | 0.5717 (3) | 0.09006 (18) | 0.58564 (13) | 0.0212 (5) | |
H2 | 0.4646 | 0.0981 | 0.5882 | 0.025* | |
C3 | 0.6280 (3) | 0.1004 (2) | 0.66122 (12) | 0.0213 (5) | |
O1 | 0.70426 (18) | 0.17296 (14) | 0.68158 (8) | 0.0273 (4) | |
O2 | 0.57971 (18) | 0.01641 (13) | 0.69861 (8) | 0.0242 (4) | |
C4 | 0.6154 (3) | 0.0011 (2) | 0.77501 (13) | 0.0245 (6) | |
C5 | 0.5527 (3) | −0.1102 (2) | 0.79020 (14) | 0.0321 (7) | |
H5A | 0.4503 | −0.1108 | 0.7777 | 0.048* | |
H5B | 0.5636 | −0.1268 | 0.8406 | 0.048* | |
H5C | 0.6037 | −0.1649 | 0.7621 | 0.048* | |
C6 | 0.5399 (3) | 0.0886 (2) | 0.81728 (13) | 0.0306 (6) | |
H6A | 0.5768 | 0.1600 | 0.8032 | 0.046* | |
H6B | 0.5581 | 0.0773 | 0.8678 | 0.046* | |
H6C | 0.4361 | 0.0853 | 0.8082 | 0.046* | |
C7 | 0.7776 (3) | 0.0003 (2) | 0.78534 (15) | 0.0315 (7) | |
H7A | 0.8220 | −0.0472 | 0.7499 | 0.047* | |
H7B | 0.8003 | −0.0267 | 0.8328 | 0.047* | |
H7C | 0.8152 | 0.0742 | 0.7800 | 0.047* | |
N1 | 0.6244 (2) | 0.17903 (15) | 0.54236 (11) | 0.0231 (4) | |
H1 | 0.7050 | 0.2124 | 0.5537 | 0.028* | |
C8 | 0.5496 (3) | 0.21029 (19) | 0.48489 (12) | 0.0227 (5) | |
O3 | 0.42824 (18) | 0.18198 (14) | 0.47025 (8) | 0.0284 (4) | |
O4 | 0.62994 (17) | 0.27758 (13) | 0.44516 (9) | 0.0284 (4) | |
C9 | 0.5719 (3) | 0.3031 (2) | 0.37576 (12) | 0.0226 (5) | |
H9A | 0.4796 | 0.3427 | 0.3800 | 0.027* | |
H9B | 0.5557 | 0.2360 | 0.3480 | 0.027* | |
C10 | 0.6849 (3) | 0.37328 (18) | 0.34118 (11) | 0.0209 (5) | |
H10 | 0.7805 | 0.3368 | 0.3462 | 0.025* | |
C11 | 0.6964 (2) | 0.48775 (18) | 0.37084 (12) | 0.0200 (5) | |
C12 | 0.6864 (2) | 0.56408 (18) | 0.31621 (11) | 0.0185 (4) | |
C13 | 0.6658 (3) | 0.50630 (18) | 0.24891 (11) | 0.0193 (5) | |
C14 | 0.6576 (3) | 0.39513 (18) | 0.26291 (11) | 0.0189 (5) | |
C15 | 0.7107 (2) | 0.52175 (19) | 0.44052 (13) | 0.0228 (6) | |
H15 | 0.7168 | 0.4702 | 0.4778 | 0.027* | |
C16 | 0.7159 (3) | 0.6322 (2) | 0.45491 (15) | 0.0280 (5) | |
H16 | 0.7247 | 0.6563 | 0.5025 | 0.034* | |
C17 | 0.7085 (3) | 0.7081 (2) | 0.40037 (13) | 0.0278 (6) | |
H17 | 0.7129 | 0.7834 | 0.4111 | 0.033* | |
C18 | 0.6946 (3) | 0.67478 (19) | 0.33056 (12) | 0.0239 (5) | |
H18 | 0.6908 | 0.7265 | 0.2933 | 0.029* | |
C19 | 0.6540 (2) | 0.5454 (2) | 0.18034 (11) | 0.0211 (5) | |
H19 | 0.6611 | 0.6208 | 0.1705 | 0.025* | |
C20 | 0.6315 (3) | 0.4704 (2) | 0.12645 (12) | 0.0248 (6) | |
H20 | 0.6240 | 0.4952 | 0.0790 | 0.030* | |
C21 | 0.6197 (3) | 0.3605 (2) | 0.14039 (13) | 0.0268 (6) | |
H21 | 0.6016 | 0.3113 | 0.1027 | 0.032* | |
C22 | 0.6342 (2) | 0.3212 (2) | 0.20891 (13) | 0.0239 (6) | |
H22 | 0.6283 | 0.2457 | 0.2185 | 0.029* |
Atomic displacement parameters (Å2) top
U11 | U22 | U33 | U12 | U13 | U23 | |
I1 | 0.02977 (8) | 0.03313 (9) | 0.03726 (9) | 0.00558 (8) | −0.00197 (8) | −0.00894 (8) |
C1 | 0.0219 (12) | 0.0289 (13) | 0.0268 (13) | −0.0033 (10) | −0.0032 (12) | −0.0010 (12) |
C2 | 0.0185 (12) | 0.0196 (12) | 0.0255 (13) | −0.0027 (10) | −0.0003 (10) | 0.0026 (10) |
C3 | 0.0209 (13) | 0.0211 (12) | 0.0220 (13) | 0.0042 (10) | 0.0050 (10) | 0.0007 (10) |
O1 | 0.0340 (11) | 0.0236 (9) | 0.0245 (9) | −0.0097 (8) | −0.0013 (7) | 0.0001 (7) |
O2 | 0.0247 (10) | 0.0258 (9) | 0.0221 (9) | −0.0071 (7) | −0.0028 (7) | 0.0057 (7) |
C4 | 0.0247 (13) | 0.0295 (14) | 0.0192 (13) | −0.0022 (11) | −0.0014 (11) | 0.0054 (11) |
C5 | 0.0296 (16) | 0.0340 (15) | 0.0326 (16) | −0.0048 (12) | −0.0021 (12) | 0.0138 (12) |
C6 | 0.0270 (14) | 0.0374 (16) | 0.0274 (14) | −0.0013 (12) | −0.0010 (11) | 0.0010 (11) |
C7 | 0.0219 (15) | 0.0317 (14) | 0.0409 (17) | 0.0005 (12) | −0.0028 (12) | 0.0078 (13) |
N1 | 0.0240 (10) | 0.0251 (10) | 0.0202 (10) | −0.0049 (8) | −0.0033 (9) | 0.0074 (9) |
C8 | 0.0274 (15) | 0.0183 (12) | 0.0225 (13) | −0.0006 (11) | 0.0035 (10) | 0.0018 (10) |
O3 | 0.0233 (9) | 0.0325 (10) | 0.0296 (11) | −0.0076 (8) | −0.0053 (7) | 0.0060 (7) |
O4 | 0.0301 (10) | 0.0321 (9) | 0.0232 (9) | −0.0096 (7) | −0.0064 (8) | 0.0107 (8) |
C9 | 0.0242 (13) | 0.0213 (13) | 0.0222 (13) | −0.0032 (10) | −0.0047 (10) | 0.0050 (10) |
C10 | 0.0212 (13) | 0.0203 (12) | 0.0211 (12) | 0.0005 (11) | −0.0011 (11) | 0.0011 (9) |
C11 | 0.0145 (13) | 0.0201 (11) | 0.0253 (13) | −0.0018 (9) | −0.0022 (10) | 0.0015 (9) |
C12 | 0.0120 (10) | 0.0220 (11) | 0.0215 (11) | −0.0007 (11) | 0.0008 (9) | 0.0009 (10) |
C13 | 0.0125 (11) | 0.0227 (11) | 0.0226 (12) | −0.0007 (11) | 0.0019 (11) | 0.0002 (9) |
C14 | 0.0145 (12) | 0.0231 (11) | 0.0192 (12) | 0.0006 (10) | 0.0015 (10) | 0.0001 (9) |
C15 | 0.0220 (13) | 0.0264 (12) | 0.0198 (13) | −0.0020 (9) | −0.0043 (9) | 0.0021 (9) |
C16 | 0.0258 (13) | 0.0338 (14) | 0.0244 (13) | −0.0008 (10) | −0.0041 (12) | −0.0032 (13) |
C17 | 0.0323 (16) | 0.0202 (13) | 0.0308 (14) | −0.0022 (11) | −0.0011 (11) | −0.0053 (11) |
C18 | 0.0246 (15) | 0.0205 (12) | 0.0265 (13) | −0.0010 (11) | 0.0015 (10) | 0.0044 (10) |
C19 | 0.0159 (11) | 0.0241 (12) | 0.0235 (11) | 0.0006 (11) | 0.0009 (9) | 0.0024 (10) |
C20 | 0.0219 (13) | 0.0381 (16) | 0.0143 (11) | 0.0006 (10) | −0.0005 (9) | 0.0029 (10) |
C21 | 0.0269 (14) | 0.0322 (15) | 0.0212 (13) | −0.0018 (11) | 0.0012 (10) | −0.0068 (11) |
C22 | 0.0242 (15) | 0.0208 (13) | 0.0267 (13) | −0.0018 (10) | 0.0010 (10) | −0.0009 (10) |
Geometric parameters (Å, º) top
I1—C1 | 2.155 (2) | C9—H9A | 0.990 |
C1—H1A | 0.990 | C9—H9B | 0.990 |
C1—H1B | 0.990 | C9—C10 | 1.509 (3) |
C1—C2 | 1.519 (3) | C10—H10 | 1.000 |
C2—H2 | 1.000 | C10—C11 | 1.521 (3) |
C2—C3 | 1.527 (3) | C10—C14 | 1.525 (3) |
C2—N1 | 1.453 (3) | C11—C12 | 1.400 (3) |
C3—O1 | 1.203 (3) | C11—C15 | 1.388 (3) |
C3—O2 | 1.331 (3) | C12—C13 | 1.470 (3) |
O2—C4 | 1.494 (3) | C12—C18 | 1.392 (3) |
C4—C5 | 1.517 (3) | C13—C14 | 1.397 (3) |
C4—C6 | 1.514 (4) | C13—C19 | 1.387 (3) |
C4—C7 | 1.520 (4) | C14—C22 | 1.385 (3) |
C5—H5A | 0.980 | C15—H15 | 0.950 |
C5—H5B | 0.980 | C15—C16 | 1.388 (4) |
C5—H5C | 0.980 | C16—H16 | 0.950 |
C6—H6A | 0.980 | C16—C17 | 1.394 (4) |
C6—H6B | 0.980 | C17—H17 | 0.950 |
C6—H6C | 0.980 | C17—C18 | 1.388 (3) |
C7—H7A | 0.980 | C18—H18 | 0.950 |
C7—H7B | 0.980 | C19—H19 | 0.950 |
C7—H7C | 0.980 | C19—C20 | 1.391 (3) |
N1—H1 | 0.880 | C20—H20 | 0.950 |
N1—C8 | 1.346 (3) | C20—C21 | 1.384 (4) |
C8—O3 | 1.212 (3) | C21—H21 | 0.950 |
C8—O4 | 1.345 (3) | C21—C22 | 1.389 (3) |
O4—C9 | 1.452 (3) | C22—H22 | 0.950 |
I1—C1—H1A | 109.3 | O4—C9—H9B | 110.8 |
I1—C1—H1B | 109.3 | O4—C9—C10 | 104.91 (19) |
I1—C1—C2 | 111.81 (16) | H9A—C9—H9B | 108.8 |
H1A—C1—H1B | 107.9 | H9A—C9—C10 | 110.8 |
H1A—C1—C2 | 109.3 | H9B—C9—C10 | 110.8 |
H1B—C1—C2 | 109.3 | C9—C10—H10 | 108.6 |
C1—C2—H2 | 106.7 | C9—C10—C11 | 114.9 (2) |
C1—C2—C3 | 112.58 (19) | C9—C10—C14 | 114.0 (2) |
C1—C2—N1 | 113.24 (19) | H10—C10—C11 | 108.6 |
H2—C2—C3 | 106.7 | H10—C10—C14 | 108.6 |
H2—C2—N1 | 106.7 | C11—C10—C14 | 101.87 (18) |
C3—C2—N1 | 110.4 (2) | C10—C11—C12 | 110.24 (19) |
C2—C3—O1 | 124.3 (2) | C10—C11—C15 | 129.5 (2) |
C2—C3—O2 | 108.4 (2) | C12—C11—C15 | 120.2 (2) |
O1—C3—O2 | 127.3 (2) | C11—C12—C13 | 108.8 (2) |
C3—O2—C4 | 122.46 (19) | C11—C12—C18 | 120.7 (2) |
O2—C4—C5 | 102.2 (2) | C13—C12—C18 | 130.5 (2) |
O2—C4—C6 | 108.5 (2) | C12—C13—C14 | 108.52 (19) |
O2—C4—C7 | 110.2 (2) | C12—C13—C19 | 130.6 (2) |
C5—C4—C6 | 111.5 (2) | C14—C13—C19 | 120.9 (2) |
C5—C4—C7 | 110.5 (2) | C10—C14—C13 | 110.35 (19) |
C6—C4—C7 | 113.3 (2) | C10—C14—C22 | 128.7 (2) |
C4—C5—H5A | 109.5 | C13—C14—C22 | 120.9 (2) |
C4—C5—H5B | 109.5 | C11—C15—H15 | 120.5 |
C4—C5—H5C | 109.5 | C11—C15—C16 | 119.0 (2) |
H5A—C5—H5B | 109.5 | H15—C15—C16 | 120.5 |
H5A—C5—H5C | 109.5 | C15—C16—H16 | 119.6 |
H5B—C5—H5C | 109.5 | C15—C16—C17 | 120.7 (3) |
C4—C6—H6A | 109.5 | H16—C16—C17 | 119.6 |
C4—C6—H6B | 109.5 | C16—C17—H17 | 119.7 |
C4—C6—H6C | 109.5 | C16—C17—C18 | 120.6 (2) |
H6A—C6—H6B | 109.5 | H17—C17—C18 | 119.7 |
H6A—C6—H6C | 109.5 | C12—C18—C17 | 118.7 (2) |
H6B—C6—H6C | 109.5 | C12—C18—H18 | 120.7 |
C4—C7—H7A | 109.5 | C17—C18—H18 | 120.7 |
C4—C7—H7B | 109.5 | C13—C19—H19 | 121.1 |
C4—C7—H7C | 109.5 | C13—C19—C20 | 117.8 (2) |
H7A—C7—H7B | 109.5 | H19—C19—C20 | 121.1 |
H7A—C7—H7C | 109.5 | C19—C20—H20 | 119.3 |
H7B—C7—H7C | 109.5 | C19—C20—C21 | 121.5 (2) |
C2—N1—H1 | 120.1 | H20—C20—C21 | 119.3 |
C2—N1—C8 | 119.8 (2) | C20—C21—H21 | 119.7 |
H1—N1—C8 | 120.1 | C20—C21—C22 | 120.7 (2) |
N1—C8—O3 | 125.6 (2) | H21—C21—C22 | 119.7 |
N1—C8—O4 | 109.9 (2) | C14—C22—C21 | 118.3 (2) |
O3—C8—O4 | 124.5 (2) | C14—C22—H22 | 120.9 |
C8—O4—C9 | 115.59 (19) | C21—C22—H22 | 120.9 |
O4—C9—H9A | 110.8 | ||
I1—C1—C2—C3 | −61.0 (2) | C15—C11—C12—C18 | 1.9 (3) |
I1—C1—C2—N1 | 65.1 (2) | C11—C12—C13—C14 | 2.3 (3) |
C1—C2—C3—O1 | 128.3 (2) | C11—C12—C13—C19 | −178.0 (3) |
C1—C2—C3—O2 | −51.1 (2) | C18—C12—C13—C14 | −176.9 (3) |
N1—C2—C3—O1 | 0.6 (3) | C18—C12—C13—C19 | 2.7 (5) |
N1—C2—C3—O2 | −178.76 (18) | C12—C13—C14—C10 | −4.6 (3) |
C2—C3—O2—C4 | 179.77 (19) | C12—C13—C14—C22 | 178.2 (2) |
O1—C3—O2—C4 | 0.4 (4) | C19—C13—C14—C10 | 175.7 (2) |
C3—O2—C4—C5 | −173.2 (2) | C19—C13—C14—C22 | −1.5 (4) |
C3—O2—C4—C6 | 68.9 (3) | C9—C10—C14—C13 | 129.2 (2) |
C3—O2—C4—C7 | −55.7 (3) | C9—C10—C14—C22 | −53.9 (3) |
C1—C2—N1—C8 | 78.1 (3) | C11—C10—C14—C13 | 4.8 (3) |
C3—C2—N1—C8 | −154.7 (2) | C11—C10—C14—C22 | −178.3 (2) |
C2—N1—C8—O3 | 11.7 (4) | C10—C11—C15—C16 | −178.5 (2) |
C2—N1—C8—O4 | −167.77 (19) | C12—C11—C15—C16 | −0.5 (3) |
N1—C8—O4—C9 | 170.05 (19) | C11—C15—C16—C17 | −0.6 (4) |
O3—C8—O4—C9 | −9.4 (3) | C15—C16—C17—C18 | 0.5 (4) |
C8—O4—C9—C10 | −176.84 (19) | C16—C17—C18—C12 | 0.9 (4) |
O4—C9—C10—C11 | −72.3 (2) | C11—C12—C18—C17 | −2.0 (4) |
O4—C9—C10—C14 | 170.72 (18) | C13—C12—C18—C17 | 177.2 (2) |
C9—C10—C11—C12 | −127.1 (2) | C12—C13—C19—C20 | −178.6 (2) |
C9—C10—C11—C15 | 51.1 (4) | C14—C13—C19—C20 | 1.0 (4) |
C14—C10—C11—C12 | −3.4 (3) | C13—C19—C20—C21 | 0.6 (4) |
C14—C10—C11—C15 | 174.8 (2) | C19—C20—C21—C22 | −1.8 (4) |
C10—C11—C12—C13 | 0.9 (3) | C10—C14—C22—C21 | −176.4 (2) |
C10—C11—C12—C18 | −179.8 (2) | C13—C14—C22—C21 | 0.2 (4) |
C15—C11—C12—C13 | −177.5 (2) | C20—C21—C22—C14 | 1.4 (4) |
Hydrogen-bond geometry (Å, º) top
D—H···A | D—H | H···A | D···A | D—H···A |
N1—H1···O3i | 0.88 | 2.49 | 3.309 (3) | 155 |
Symmetry code: (i) x+1/2, −y+1/2, −z+1. |
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