organic compounds
3-O-Benzhydryl-2,5-dideoxy-2,5-imino-2-C-methyl-L-lyxono-1,4-lactone
aDepartment of Organic Chemistry, Chemical Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, England, and bDepartment of Chemical Crystallography, Chemical Research Laboratory, University of Oxford, Mansfield Road, Oxford OX1 3TA, England
*Correspondence e-mail: victoria.booth@chem.ox.ac.uk
The title bicyclic lactone, C19H19NO3, is an intermediate in the synthesis of chiral α-methylprolines and branched C-methyl pyrrolidines; the was determined by the use of D-erythronolactone as the starting material. It exhibits no unusual crystal packing features, and each molecule acts as a donor and acceptor for one C—H⋯O hydrogen bond.
Related literature
For use of ); Ireland et al. (1983); Hotchkiss et al. (2006, 2007a,b); Dukhan et al. (2005); Rao et al. (2008); Punzo et al. (2005a,b); Da Cruz et al. (2008). For related crystallographic literature see: Larson (1970); Prince (1982); Watkin (1994).
in synthesis see: Monneret & Florent (1994Experimental
Crystal data
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Refinement
|
Data collection: COLLECT (Nonius, 1997-2001).; cell DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK; program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003); molecular graphics: CAMERON (Watkin et al., 1996); software used to prepare material for publication: CRYSTALS.
Supporting information
10.1107/S1600536808027888/cs2089sup1.cif
contains datablock I. DOI:Structure factors: contains datablock I. DOI: 10.1107/S1600536808027888/cs2089Isup2.hkl
The title compound was recrystallized from cyclohexane and diethyl ether: m.p. 116–118°C; [α]D21 -26.0 (c, 1.0 in MeCN).
In the absence of significant
Friedel pairs were merged. The H atoms were all located in a difference map, but those attached to carbon atoms were repositioned geometrically. The H atoms were initially refined with soft restraints on the bond lengths and angles to regularize their geometry (C—H in the range 0.93–0.98, N—H in the range 0.86–0.89 N—H to 0.86 O—H = 0.82 Å) and Uiso(H) (in the range 1.2–1.5 times Ueq of the parent atom), after which the positions were refined with riding constraints.Data collection: COLLECT (Nonius, 1997-2001).; cell
DENZO/SCALEPACK (Otwinowski & Minor, 1997); data reduction: DENZO/SCALEPACK (Otwinowski & Minor, 1997); program(s) used to solve structure: SIR92 (Altomare et al., 1994); program(s) used to refine structure: CRYSTALS (Betteridge et al., 2003); molecular graphics: CAMERON (Watkin et al., 1996); software used to prepare material for publication: CRYSTALS (Betteridge et al., 2003).C19H19NO3 | F(000) = 656 |
Mr = 309.36 | Dx = 1.286 Mg m−3 |
Orthorhombic, P212121 | Mo Kα radiation, λ = 0.71073 Å |
Hall symbol: P 2ac 2ab | Cell parameters from 6711 reflections |
a = 9.0336 (2) Å | θ = 5–27° |
b = 10.0498 (2) Å | µ = 0.09 mm−1 |
c = 17.5941 (4) Å | T = 150 K |
V = 1597.30 (6) Å3 | Block, colourless |
Z = 4 | 0.30 × 0.25 × 0.25 mm |
Nonius KappaCCD area-detector diffractometer | 1411 reflections with I > 2σ(I) |
Graphite monochromator | Rint = 0.053 |
ω scans | θmax = 27.5°, θmin = 5.2° |
Absorption correction: multi-scan (DENZO/SCALEPACK; Otwinowski & Minor, 1997) | h = −11→11 |
Tmin = 0.94, Tmax = 0.98 | k = −13→12 |
25603 measured reflections | l = −22→22 |
2071 independent reflections |
Refinement on F2 | Hydrogen site location: inferred from neighbouring sites |
Least-squares matrix: full | H atoms treated by a mixture of independent and constrained refinement |
R[F2 > 2σ(F2)] = 0.029 | Method, part 1, Chebychev polynomial, (Watkin, 1994) [weight] = 1.0/[A0*T0(x) + A1*T1(x) ··· + An-1]*Tn-1(x)] where Ai are the Chebychev coefficients listed below and x = F /Fmax Method = Robust Weighting (Prince, 1982) W = [weight] * [1-(deltaF/6*sigmaF)2]2 Ai are: 16.5 25.4 13.4 3.97 |
wR(F2) = 0.101 | (Δ/σ)max = 0.000186 |
S = 0.86 | Δρmax = 0.21 e Å−3 |
2071 reflections | Δρmin = −0.21 e Å−3 |
212 parameters | Extinction correction: Larson (1970), Equation 22 |
0 restraints | Extinction coefficient: 420 (70) |
Primary atom site location: structure-invariant direct methods |
C19H19NO3 | V = 1597.30 (6) Å3 |
Mr = 309.36 | Z = 4 |
Orthorhombic, P212121 | Mo Kα radiation |
a = 9.0336 (2) Å | µ = 0.09 mm−1 |
b = 10.0498 (2) Å | T = 150 K |
c = 17.5941 (4) Å | 0.30 × 0.25 × 0.25 mm |
Nonius KappaCCD area-detector diffractometer | 2071 independent reflections |
Absorption correction: multi-scan (DENZO/SCALEPACK; Otwinowski & Minor, 1997) | 1411 reflections with I > 2σ(I) |
Tmin = 0.94, Tmax = 0.98 | Rint = 0.053 |
25603 measured reflections |
R[F2 > 2σ(F2)] = 0.029 | 0 restraints |
wR(F2) = 0.101 | H atoms treated by a mixture of independent and constrained refinement |
S = 0.86 | Δρmax = 0.21 e Å−3 |
2071 reflections | Δρmin = −0.21 e Å−3 |
212 parameters |
x | y | z | Uiso*/Ueq | ||
O1 | 0.68597 (16) | 0.81026 (14) | 0.31734 (9) | 0.0272 | |
C2 | 0.6994 (2) | 0.69016 (19) | 0.27608 (12) | 0.0242 | |
C3 | 0.7190 (3) | 0.5647 (2) | 0.32511 (13) | 0.0286 | |
O4 | 0.76321 (17) | 0.46691 (14) | 0.26720 (9) | 0.0310 | |
C5 | 0.8514 (3) | 0.5332 (2) | 0.21745 (12) | 0.0301 | |
C6 | 0.8569 (2) | 0.6776 (2) | 0.24385 (12) | 0.0281 | |
N7 | 0.9525 (2) | 0.6653 (2) | 0.31282 (12) | 0.0325 | |
C8 | 0.8577 (3) | 0.5979 (2) | 0.37011 (13) | 0.0337 | |
C9 | 0.9106 (3) | 0.7768 (3) | 0.18667 (15) | 0.0392 | |
O10 | 0.9132 (2) | 0.47855 (18) | 0.16574 (10) | 0.0420 | |
C11 | 0.5358 (2) | 0.8483 (2) | 0.33392 (12) | 0.0251 | |
C12 | 0.5418 (2) | 0.9877 (2) | 0.36769 (12) | 0.0266 | |
C13 | 0.6550 (3) | 1.0751 (2) | 0.34846 (13) | 0.0315 | |
C14 | 0.6565 (3) | 1.2033 (2) | 0.37762 (14) | 0.0370 | |
C15 | 0.5459 (3) | 1.2459 (2) | 0.42665 (15) | 0.0406 | |
C16 | 0.4328 (3) | 1.1595 (2) | 0.44577 (15) | 0.0402 | |
C17 | 0.4305 (3) | 1.0309 (2) | 0.41629 (13) | 0.0344 | |
C18 | 0.4604 (2) | 0.74727 (19) | 0.38447 (11) | 0.0253 | |
C19 | 0.5194 (3) | 0.7164 (2) | 0.45543 (12) | 0.0322 | |
C20 | 0.4554 (3) | 0.6179 (3) | 0.50012 (13) | 0.0405 | |
C21 | 0.3303 (3) | 0.5504 (2) | 0.47385 (16) | 0.0422 | |
C22 | 0.2698 (3) | 0.5832 (2) | 0.40451 (16) | 0.0397 | |
C23 | 0.3342 (3) | 0.6812 (2) | 0.35977 (13) | 0.0312 | |
H21 | 0.6217 | 0.6791 | 0.2367 | 0.0282* | |
H31 | 0.6344 | 0.5365 | 0.3548 | 0.0341* | |
H81 | 0.8335 | 0.6581 | 0.4126 | 0.0399* | |
H82 | 0.9062 | 0.5176 | 0.3880 | 0.0400* | |
H91 | 1.0125 | 0.7635 | 0.1745 | 0.0585* | |
H92 | 0.9002 | 0.8665 | 0.2083 | 0.0596* | |
H93 | 0.8509 | 0.7721 | 0.1411 | 0.0587* | |
H111 | 0.4814 | 0.8523 | 0.2851 | 0.0297* | |
H131 | 0.7306 | 1.0474 | 0.3158 | 0.0374* | |
H141 | 0.7337 | 1.2628 | 0.3636 | 0.0445* | |
H151 | 0.5485 | 1.3315 | 0.4472 | 0.0487* | |
H161 | 0.3564 | 1.1873 | 0.4788 | 0.0478* | |
H171 | 0.3527 | 0.9733 | 0.4299 | 0.0420* | |
H191 | 0.6040 | 0.7642 | 0.4731 | 0.0384* | |
H201 | 0.4969 | 0.5968 | 0.5471 | 0.0498* | |
H211 | 0.2866 | 0.4832 | 0.5036 | 0.0514* | |
H221 | 0.1848 | 0.5371 | 0.3861 | 0.0482* | |
H231 | 0.2913 | 0.7017 | 0.3118 | 0.0394* | |
H1 | 0.980 (4) | 0.748 (3) | 0.3251 (17) | 0.0433* |
U11 | U22 | U33 | U12 | U13 | U23 | |
O1 | 0.0237 (7) | 0.0228 (7) | 0.0350 (7) | 0.0012 (6) | 0.0009 (6) | −0.0054 (6) |
C2 | 0.0247 (9) | 0.0202 (9) | 0.0278 (9) | −0.0005 (8) | 0.0007 (8) | −0.0031 (8) |
C3 | 0.0329 (11) | 0.0225 (9) | 0.0303 (10) | 0.0008 (8) | 0.0044 (9) | −0.0034 (8) |
O4 | 0.0330 (8) | 0.0242 (7) | 0.0359 (8) | 0.0010 (6) | 0.0024 (7) | −0.0046 (7) |
C5 | 0.0280 (10) | 0.0300 (10) | 0.0324 (10) | 0.0045 (9) | −0.0011 (9) | −0.0022 (9) |
C6 | 0.0243 (10) | 0.0261 (9) | 0.0340 (10) | 0.0013 (8) | 0.0015 (8) | −0.0012 (9) |
N7 | 0.0264 (9) | 0.0306 (9) | 0.0404 (10) | 0.0011 (8) | −0.0073 (8) | −0.0026 (8) |
C8 | 0.0375 (12) | 0.0306 (11) | 0.0331 (11) | 0.0063 (10) | −0.0040 (10) | 0.0005 (9) |
C9 | 0.0358 (12) | 0.0361 (12) | 0.0457 (13) | −0.0005 (10) | 0.0122 (11) | 0.0078 (11) |
O10 | 0.0462 (10) | 0.0399 (9) | 0.0398 (9) | 0.0087 (8) | 0.0086 (8) | −0.0084 (8) |
C11 | 0.0224 (9) | 0.0270 (9) | 0.0260 (9) | 0.0031 (8) | −0.0017 (8) | −0.0001 (8) |
C12 | 0.0285 (10) | 0.0247 (9) | 0.0265 (9) | 0.0045 (8) | −0.0011 (8) | 0.0008 (8) |
C13 | 0.0307 (11) | 0.0267 (10) | 0.0372 (11) | 0.0034 (9) | 0.0025 (10) | 0.0025 (9) |
C14 | 0.0385 (12) | 0.0246 (10) | 0.0478 (13) | −0.0016 (10) | 0.0034 (11) | 0.0045 (10) |
C15 | 0.0496 (15) | 0.0239 (11) | 0.0482 (14) | 0.0065 (10) | 0.0007 (12) | −0.0049 (9) |
C16 | 0.0421 (14) | 0.0335 (12) | 0.0452 (13) | 0.0062 (11) | 0.0100 (11) | −0.0051 (10) |
C17 | 0.0361 (12) | 0.0289 (11) | 0.0383 (12) | 0.0023 (10) | 0.0079 (10) | −0.0004 (9) |
C18 | 0.0265 (10) | 0.0230 (9) | 0.0265 (10) | 0.0029 (8) | 0.0018 (9) | −0.0030 (8) |
C19 | 0.0408 (13) | 0.0287 (10) | 0.0272 (10) | 0.0053 (11) | −0.0017 (10) | −0.0039 (8) |
C20 | 0.0570 (16) | 0.0362 (12) | 0.0283 (10) | 0.0138 (11) | 0.0069 (12) | 0.0020 (10) |
C21 | 0.0474 (14) | 0.0292 (11) | 0.0501 (14) | 0.0055 (11) | 0.0209 (13) | 0.0051 (10) |
C22 | 0.0348 (12) | 0.0299 (11) | 0.0544 (15) | −0.0019 (10) | 0.0093 (12) | −0.0035 (11) |
C23 | 0.0284 (10) | 0.0295 (10) | 0.0356 (10) | 0.0009 (8) | 0.0004 (9) | −0.0038 (9) |
O1—C2 | 1.414 (2) | C12—C13 | 1.390 (3) |
O1—C11 | 1.439 (2) | C12—C17 | 1.389 (3) |
C2—C3 | 1.538 (3) | C13—C14 | 1.387 (3) |
C2—C6 | 1.537 (3) | C13—H131 | 0.935 |
C2—H21 | 0.992 | C14—C15 | 1.388 (4) |
C3—O4 | 1.471 (2) | C14—H141 | 0.951 |
C3—C8 | 1.519 (3) | C15—C16 | 1.382 (4) |
C3—H31 | 0.968 | C15—H151 | 0.934 |
O4—C5 | 1.358 (3) | C16—C17 | 1.393 (3) |
C5—C6 | 1.524 (3) | C16—H161 | 0.945 |
C5—O10 | 1.200 (3) | C17—H171 | 0.941 |
C6—N7 | 1.495 (3) | C18—C19 | 1.393 (3) |
C6—C9 | 1.497 (3) | C18—C23 | 1.389 (3) |
N7—C8 | 1.486 (3) | C19—C20 | 1.390 (4) |
N7—H1 | 0.89 (3) | C19—H191 | 0.954 |
C8—H81 | 0.986 | C20—C21 | 1.397 (4) |
C8—H82 | 0.971 | C20—H201 | 0.932 |
C9—H91 | 0.955 | C21—C22 | 1.377 (4) |
C9—H92 | 0.983 | C21—H211 | 0.942 |
C9—H93 | 0.968 | C22—C23 | 1.389 (4) |
C11—C12 | 1.523 (3) | C22—H221 | 0.954 |
C11—C18 | 1.512 (3) | C23—H231 | 0.952 |
C11—H111 | 0.990 | ||
C2—O1—C11 | 114.34 (15) | C12—C11—C18 | 113.84 (17) |
O1—C2—C3 | 114.94 (16) | O1—C11—H111 | 107.6 |
O1—C2—C6 | 109.83 (16) | C12—C11—H111 | 108.5 |
C3—C2—C6 | 91.88 (16) | C18—C11—H111 | 108.3 |
O1—C2—H21 | 113.2 | C11—C12—C13 | 120.81 (19) |
C3—C2—H21 | 112.4 | C11—C12—C17 | 120.2 (2) |
C6—C2—H21 | 112.8 | C13—C12—C17 | 119.0 (2) |
C2—C3—O4 | 100.99 (16) | C12—C13—C14 | 120.3 (2) |
C2—C3—C8 | 101.98 (17) | C12—C13—H131 | 119.9 |
O4—C3—C8 | 106.51 (17) | C14—C13—H131 | 119.8 |
C2—C3—H31 | 116.9 | C13—C14—C15 | 120.6 (2) |
O4—C3—H31 | 113.0 | C13—C14—H141 | 119.7 |
C8—C3—H31 | 115.7 | C15—C14—H141 | 119.7 |
C3—O4—C5 | 106.11 (16) | C14—C15—C16 | 119.4 (2) |
O4—C5—C6 | 106.84 (17) | C14—C15—H151 | 120.5 |
O4—C5—O10 | 122.5 (2) | C16—C15—H151 | 120.2 |
C6—C5—O10 | 130.6 (2) | C15—C16—C17 | 120.2 (2) |
C2—C6—C5 | 99.24 (16) | C15—C16—H161 | 120.3 |
C2—C6—N7 | 104.02 (17) | C17—C16—H161 | 119.5 |
C5—C6—N7 | 100.82 (17) | C16—C17—C12 | 120.6 (2) |
C2—C6—C9 | 119.55 (18) | C16—C17—H171 | 119.2 |
C5—C6—C9 | 116.07 (19) | C12—C17—H171 | 120.3 |
N7—C6—C9 | 114.42 (19) | C11—C18—C19 | 120.3 (2) |
C6—N7—C8 | 104.77 (16) | C11—C18—C23 | 120.47 (19) |
C6—N7—H1 | 106 (2) | C19—C18—C23 | 119.2 (2) |
C8—N7—H1 | 115 (2) | C18—C19—C20 | 120.4 (2) |
C3—C8—N7 | 102.82 (18) | C18—C19—H191 | 119.1 |
C3—C8—H81 | 110.3 | C20—C19—H191 | 120.5 |
N7—C8—H81 | 111.3 | C19—C20—C21 | 119.7 (2) |
C3—C8—H82 | 111.0 | C19—C20—H201 | 119.8 |
N7—C8—H82 | 109.7 | C21—C20—H201 | 120.5 |
H81—C8—H82 | 111.3 | C20—C21—C22 | 119.9 (2) |
C6—C9—H91 | 111.7 | C20—C21—H211 | 120.3 |
C6—C9—H92 | 108.6 | C22—C21—H211 | 119.9 |
H91—C9—H92 | 107.9 | C21—C22—C23 | 120.4 (3) |
C6—C9—H93 | 110.2 | C21—C22—H221 | 120.3 |
H91—C9—H93 | 110.1 | C23—C22—H221 | 119.3 |
H92—C9—H93 | 108.2 | C18—C23—C22 | 120.4 (2) |
O1—C11—C12 | 106.90 (17) | C18—C23—H231 | 120.5 |
O1—C11—C18 | 111.45 (16) | C22—C23—H231 | 119.1 |
D—H···A | D—H | H···A | D···A | D—H···A |
C20—H201···O10i | 0.93 | 2.36 | 3.293 (3) | 174 |
N7—H1···O10ii | 0.89 (2) | 2.52 (3) | 3.395 (3) | 168 |
Symmetry codes: (i) −x+3/2, −y+1, z+1/2; (ii) −x+2, y+1/2, −z+1/2. |
Experimental details
Crystal data | |
Chemical formula | C19H19NO3 |
Mr | 309.36 |
Crystal system, space group | Orthorhombic, P212121 |
Temperature (K) | 150 |
a, b, c (Å) | 9.0336 (2), 10.0498 (2), 17.5941 (4) |
V (Å3) | 1597.30 (6) |
Z | 4 |
Radiation type | Mo Kα |
µ (mm−1) | 0.09 |
Crystal size (mm) | 0.30 × 0.25 × 0.25 |
Data collection | |
Diffractometer | Nonius KappaCCD area-detector diffractometer |
Absorption correction | Multi-scan (DENZO/SCALEPACK; Otwinowski & Minor, 1997) |
Tmin, Tmax | 0.94, 0.98 |
No. of measured, independent and observed [I > 2σ(I)] reflections | 25603, 2071, 1411 |
Rint | 0.053 |
(sin θ/λ)max (Å−1) | 0.649 |
Refinement | |
R[F2 > 2σ(F2)], wR(F2), S | 0.029, 0.101, 0.86 |
No. of reflections | 2071 |
No. of parameters | 212 |
H-atom treatment | H atoms treated by a mixture of independent and constrained refinement |
Δρmax, Δρmin (e Å−3) | 0.21, −0.21 |
Computer programs: COLLECT (Nonius, 1997-2001)., DENZO/SCALEPACK (Otwinowski & Minor, 1997), SIR92 (Altomare et al., 1994), CRYSTALS (Betteridge et al., 2003), CAMERON (Watkin et al., 1996).
D—H···A | D—H | H···A | D···A | D—H···A |
C20—H201···O10i | 0.93 | 2.36 | 3.293 (3) | 174 |
Symmetry code: (i) −x+3/2, −y+1, z+1/2. |
Acknowledgements
Financial support (to FPC) provided by the Fundacao para a Ciencia e Tecnologia of Portugal is gratefully acknowledged. We also thank the Oxford University Crystallography Service for use of the instruments.
References
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Carbon-branched sugar lactones have hitherto been rarely used for the synthesis of enantiopure chiral targets (Monneret & Florent, 1994; Ireland et al., 1983). 2-C-Methyl-D-ribonolactone has become readily available in large amounts (Hotchkiss et al., 2007a) and has been used in the synthesis of branched α-C-nucleosides (Dukhan et al., 2005), 4-C-methylpentuloses (Rao et al., 2008) and branched imino sugars (Hotchkiss et al., 2007b). Derivatives of 2-C-methyl-D-arabinonolactone, such as 2, are accessible from D-erythronolactone 1 by addition of methyl magnesium bromide followed by further reaction with sodium cyanide (Hotchkiss et al., 2006; Punzo et al., 2005a). The tertiary alcohol 2 may be efficiently converted into the ribo-azide 3, the structure of which has been confirmed by X-ray crystallographic analysis (Da Cruz et al., 2008; Punzo et al., 2005b). The relative stereochemistry of 4 is firmly established in this paper by X-ray crystallographic analysis and the absolute configuration is defined by the use of D-erythronolactone 1 as the starting material.
The title compound exhibits no unusual crystal packing features. Each molecule acts as a donor and acceptor for one hydrogen bond, forming chains approximately parallel to the a-axis. A suggested hydrogen bond [N7 - H1 - O10] has been ignored in the packing diagram as it exceeds the limits of standard hydrogen bond length (2.52 Å)