Di-tert-butyl 2,2′-[(2-hydroxy­ethyl)aza­nedi­yl]diacetate

Yang, Y.; Zhu, L.; Zhang, H.

doi:10.1107/S1600536809049022

organic compounds

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ISSN: 2056-9890

Volume 65| Part 12| December 2009| Page o3167

doi:10.1107/S1600536809049022

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Di-tert-butyl 2,2′-[(2-hydroxyethyl)azanediyl]diacetate

Yang Yang,^a Lin Zhu ^a and Huabei Zhang ^a ^*

^aKey Laboratory of Radiopharmaceuticals, Ministry of Education, Department of Chemistry, Beijing Normal University, Xin Jie Kou Wai Street 19, 100875 Beijing, People's Republic of China
^*Correspondence e-mail: hbzhang@bnu.edu.cn

(Received 21 October 2009; accepted 17 November 2009; online 21 November 2009)

In the title compound, C₁₄H₂₇NO₅, the hydroxy group and one of the acetate carbonyl O atoms are linked by an intramolecular O—H⋯O hydrogen bond, forming an eight-membered ring. This interaction gives rise to an asymmetric molecular conformation.

Related literature

For details of the synthesis, see: Williams & Rapoport (1993 ); Amedio et al. (2000 ). For possible applications of the title compound, see: Yang et al. (2007 ).

Experimental

Crystal data

C₁₄H₂₇NO₅
M_r = 289.37
Orthorhombic, P b c a
a = 11.9767 (4) Å
b = 9.7187 (3) Å
c = 29.3476 (7) Å
V = 3416.00 (18) Å³
Z = 8
Mo Kα radiation
μ = 0.08 mm⁻¹
T = 296 K
0.36 × 0.21 × 0.08 mm

Data collection

Bruker SMART APEX CCD area-detector diffractometer
Absorption correction: multi-scan (SADABS; Bruker, 2007 ) T_min = 0.970, T_max = 0.993
12339 measured reflections
3958 independent reflections
2503 reflections with I > 2σ(I)
R_int = 0.022

Refinement

R[F² > 2σ(F²)] = 0.046
wR(F²) = 0.128
S = 1.02
3958 reflections
190 parameters
1 restraint
H atoms treated by a mixture of independent and constrained refinement
Δρ_max = 0.13 e Å⁻³
Δρ_min = −0.17 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
O5—H5⋯O2	0.848 (10)	2.128 (17)	2.8658 (18)	145 (2)

Data collection: SMART (Bruker, 1998 ); cell refinement: SAINT (Bruker, 2005 ); data reduction: SAINT; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: SHELXTL; software used to prepare material for publication: SHELXTL.

Supporting information

Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809049022/gk2237sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536809049022/gk2237Isup2.hkl

checkCIF report

Comment top

The aminodiacetate derivatives can find potential application when labeled by the novel ⁹⁹^mTc(CO)₂(NO)²⁺ core to explore the ⁹⁹^mTc labelled radiopharmaceuticals (Yang et al., 2007). Thus, the development of aminodiacetate derivatives may lead to obtain some new imaging agents labelled by ⁹⁹^mTc core. Here we report the crystal structure of the title compound which can be used as a precursor in the synthesis of aminodiacetate derivatives.

The molecule of the title compound is shown in Fig. 1. The molecular conformation is to a large extentd determined by the intramolecular hydrogen bond O(5)—H(5)···O(2) (Table 1) which is a part of the eight-membered ring –O(5)—C(14)—C(13)—N(1)—C(6)—C(5)—O(2)······H(5)-. In the above ring, the torsion angles N(1)—C(13)—C(14)—O(5) and N(1)—C(6)—C(5)—O(2) are -57.2 (2)° and -3.5 (2)°.

Related literature top

For details of the synthesis, see: Williams et al. (1993); Amedio et al. (2000). For possible applications of the title compound, see: Yang et al. (2007).

Experimental top

Tert-butyl 2-bromoacetate (22 g, 114 mmol) and KHCO₃ (13 g, 130 mmol) were dissolved in DMF (100 ml) at 0°C. Then 2-aminoethanol (3.2 ml, 50 mmol) was added to the solution in drops within 1 h. After adding 2-aminoethanol, the solution was heated at 55 °C for 20 h. Subsequently, the mixture was washed by the saturated NaHCO₃ solution and the crude product was extracted by ethyl acetate. After that, the organic phase was washed by saturated NaCl solution and the new organic phase was then dried by Na₂SO₄ for 48 h. After filtering the solution, the crude product was obtained. The crude product was recrystallized from ethyl acetate giving colorless block crystals of the title compound suitable for the single-crystal X-ray diffraction. IRnfrared Spectrum: 3438.3 cm^-1; 2978.5 cm^-1; 2933.7 cm^-1; 1456.8 cm^-1; 1393.6 cm^-1; 1732.0 cm^-1; 1368.6 cm^-1; 1223.5 cm^-1; 1070.9 cm^-1; 1150.5 cm^{-1. 1}H-NMR (CDCl₃, 400 MHz): 3.90 (s, 1H), 3.53 (t, J = 5.1 Hz, 2H), 3.45 (s, 4H), 2.89 (t, J = 5.1 Hz, 2H), 1.47 (s, 18H). ¹³C-NMR (CDCl₃, 400 MHz): δ 28.13, 56.64, 57.07, 59.34, 81.49, 171.46. MS:m/z 290.3 [M + H].

Computing details top

Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT (Bruker, 2005); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: SHELXTL (Sheldrick, 2008); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

Figures top

	Fig. 1. The molecule the title compound, showing the atomic numbering; the displacement ellipsoids were drawn at the 30% probability level.
	Fig. 2. The packing diagram of title compound (for clarity, all H atoms are not shown).

Di-tert-butyl 2,2'-[(2-hydroxyethyl)azanediyl]diacetate top

Crystal data top

C₁₄H₂₇NO₅	F(000) = 1264
M_r = 289.37	D_x = 1.125 Mg m⁻³
Orthorhombic, Pbca	Mo Kα radiation, λ = 0.71073 Å
Hall symbol: -P 2ac 2ab	Cell parameters from 3711 reflections
a = 11.9767 (4) Å	θ = 2.2–26.1°
b = 9.7187 (3) Å	µ = 0.08 mm⁻¹
c = 29.3476 (7) Å	T = 296 K
V = 3416.00 (18) Å³	Block, colorless
Z = 8	0.36 × 0.21 × 0.08 mm

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	3958 independent reflections
Radiation source: fine-focus sealed tube	2503 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.022
phi and ω scans	θ_max = 27.6°, θ_min = 2.2°
Absorption correction: multi-scan (SADABS; Bruker, 2007)	h = −15→10
T_min = 0.970, T_max = 0.993	k = −12→7
12339 measured reflections	l = −38→25

Refinement top

Refinement on F²	Primary atom site location: structure-invariant direct methods
Least-squares matrix: full	Secondary atom site location: difference Fourier map
R[F² > 2σ(F²)] = 0.046	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.128	H atoms treated by a mixture of independent and constrained refinement
S = 1.02	w = 1/[σ²(F_o²) + (0.0551P)² + 0.5511P] where P = (F_o² + 2F_c²)/3
3958 reflections	(Δ/σ)_max = 0.001
190 parameters	Δρ_max = 0.13 e Å⁻³
1 restraint	Δρ_min = −0.17 e Å⁻³

Crystal data top

C₁₄H₂₇NO₅	V = 3416.00 (18) Å³
M_r = 289.37	Z = 8
Orthorhombic, Pbca	Mo Kα radiation
a = 11.9767 (4) Å	µ = 0.08 mm⁻¹
b = 9.7187 (3) Å	T = 296 K
c = 29.3476 (7) Å	0.36 × 0.21 × 0.08 mm

Data collection top

Bruker SMART APEX CCD area-detector diffractometer	3958 independent reflections
Absorption correction: multi-scan (SADABS; Bruker, 2007)	2503 reflections with I > 2σ(I)
T_min = 0.970, T_max = 0.993	R_int = 0.022
12339 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.046	1 restraint
wR(F²) = 0.128	H atoms treated by a mixture of independent and constrained refinement
S = 1.02	Δρ_max = 0.13 e Å⁻³
3958 reflections	Δρ_min = −0.17 e Å⁻³
190 parameters

Special details top

Geometry. All esds (except the esd in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell esds are taken into account individually in the estimation of esds in distances, angles and torsion angles; correlations between esds in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell esds is used for estimating esds involving l.s. planes.

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 > 2sigma(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 (Å²) top

	x	y	z	U_iso*/U_eq
C1	0.52162 (16)	0.1474 (2)	0.74442 (6)	0.0719 (5)
H1A	0.5798	0.0876	0.7338	0.108*
H1B	0.4957	0.1161	0.7736	0.108*
H1C	0.5502	0.2393	0.7473	0.108*
N1	0.63856 (10)	0.38227 (12)	0.59060 (4)	0.0459 (3)
O1	0.47237 (8)	0.16745 (10)	0.66460 (3)	0.0480 (3)
C2	0.37573 (18)	0.00455 (18)	0.70716 (6)	0.0777 (6)
H2A	0.3187	0.0050	0.6842	0.117*
H2B	0.3436	−0.0212	0.7359	0.117*
H2C	0.4327	−0.0603	0.6990	0.117*
O2	0.52896 (11)	0.38533 (11)	0.67575 (4)	0.0689 (4)
C3	0.33760 (16)	0.2516 (2)	0.72143 (7)	0.0753 (5)
H3A	0.3711	0.3411	0.7233	0.113*
H3B	0.3027	0.2295	0.7500	0.113*
H3C	0.2825	0.2511	0.6977	0.113*
O3	0.69461 (11)	0.19726 (12)	0.51907 (4)	0.0714 (4)
C4	0.42619 (13)	0.14629 (15)	0.71095 (5)	0.0473 (4)
O4	0.61496 (10)	0.33760 (11)	0.46780 (3)	0.0586 (3)
C5	0.52554 (12)	0.28259 (14)	0.65316 (5)	0.0459 (3)
O5	0.73364 (13)	0.53528 (15)	0.66616 (5)	0.0839 (4)
H5	0.6636 (9)	0.524 (3)	0.6645 (9)	0.126*
C6	0.58168 (13)	0.26158 (15)	0.60781 (5)	0.0515 (4)
H6A	0.6354	0.1873	0.6107	0.062*
H6B	0.5259	0.2333	0.5858	0.062*
C7	0.61304 (14)	0.41188 (16)	0.54343 (5)	0.0545 (4)
H7A	0.6497	0.4972	0.5351	0.065*
H7B	0.5332	0.4266	0.5407	0.065*
C8	0.64704 (13)	0.30191 (16)	0.50949 (5)	0.0508 (4)
C9	0.63142 (15)	0.24561 (18)	0.42820 (5)	0.0618 (4)
C10	0.56917 (19)	0.1123 (2)	0.43595 (8)	0.0933 (7)
H10A	0.6062	0.0599	0.4592	0.140*
H10B	0.5677	0.0601	0.4082	0.140*
H10C	0.4941	0.1320	0.4454	0.140*
C11	0.75478 (18)	0.2232 (3)	0.42041 (7)	0.0882 (6)
H11A	0.7921	0.3105	0.4192	0.132*
H11B	0.7656	0.1754	0.3921	0.132*
H11C	0.7850	0.1694	0.4449	0.132*
C12	0.5793 (2)	0.3278 (2)	0.38978 (6)	0.0994 (8)
H12A	0.5028	0.3477	0.3971	0.149*
H12B	0.5824	0.2753	0.3621	0.149*
H12C	0.6195	0.4123	0.3858	0.149*
C13	0.75774 (14)	0.38686 (19)	0.60054 (5)	0.0614 (4)
H13A	0.7921	0.4587	0.5824	0.074*
H13B	0.7913	0.2999	0.5919	0.074*
C14	0.78138 (16)	0.4137 (2)	0.65010 (6)	0.0750 (5)
H14A	0.7532	0.3373	0.6680	0.090*
H14B	0.8616	0.4180	0.6545	0.090*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C1	0.0772 (12)	0.0836 (12)	0.0549 (10)	−0.0102 (10)	−0.0087 (9)	0.0146 (9)
N1	0.0527 (7)	0.0491 (7)	0.0360 (6)	−0.0043 (6)	0.0032 (5)	0.0030 (5)
O1	0.0588 (6)	0.0447 (5)	0.0406 (6)	−0.0079 (5)	0.0082 (4)	−0.0007 (4)
C2	0.1038 (14)	0.0652 (11)	0.0641 (11)	−0.0327 (11)	0.0156 (10)	0.0029 (9)
O2	0.1028 (10)	0.0468 (6)	0.0571 (7)	−0.0129 (6)	0.0304 (6)	−0.0092 (5)
C3	0.0693 (11)	0.0845 (13)	0.0722 (12)	0.0094 (10)	0.0238 (10)	0.0024 (10)
O3	0.0984 (9)	0.0681 (7)	0.0478 (7)	0.0330 (7)	−0.0009 (6)	−0.0002 (5)
C4	0.0546 (8)	0.0479 (8)	0.0393 (8)	−0.0062 (7)	0.0076 (7)	0.0034 (6)
O4	0.0760 (7)	0.0625 (7)	0.0374 (6)	0.0156 (6)	−0.0023 (5)	−0.0022 (5)
C5	0.0531 (8)	0.0434 (8)	0.0411 (8)	−0.0006 (7)	0.0041 (7)	0.0015 (6)
O5	0.1030 (10)	0.0812 (9)	0.0674 (8)	−0.0272 (9)	0.0050 (8)	−0.0216 (7)
C6	0.0611 (9)	0.0503 (8)	0.0430 (8)	−0.0069 (7)	0.0096 (7)	−0.0046 (7)
C7	0.0708 (10)	0.0530 (8)	0.0396 (8)	0.0118 (8)	0.0043 (7)	0.0023 (7)
C8	0.0577 (9)	0.0556 (9)	0.0391 (8)	0.0082 (8)	0.0040 (7)	0.0024 (7)
C9	0.0757 (11)	0.0699 (11)	0.0397 (9)	0.0100 (9)	−0.0004 (8)	−0.0105 (8)
C10	0.1030 (16)	0.0898 (15)	0.0872 (16)	−0.0163 (13)	−0.0079 (13)	−0.0199 (12)
C11	0.0809 (13)	0.1181 (17)	0.0658 (12)	0.0111 (13)	0.0199 (11)	−0.0130 (12)
C12	0.146 (2)	0.1065 (17)	0.0456 (11)	0.0351 (15)	−0.0202 (12)	−0.0077 (11)
C13	0.0567 (10)	0.0692 (11)	0.0584 (10)	−0.0081 (8)	0.0033 (8)	−0.0044 (8)
C14	0.0693 (12)	0.0905 (14)	0.0653 (12)	−0.0131 (10)	−0.0139 (9)	−0.0023 (11)

Geometric parameters (Å, º) top

C1—C4	1.507 (2)	O5—H5	0.848 (10)
C1—H1A	0.9600	C6—H6A	0.9700
C1—H1B	0.9600	C6—H6B	0.9700
C1—H1C	0.9600	C7—C8	1.517 (2)
N1—C7	1.4465 (18)	C7—H7A	0.9700
N1—C6	1.4475 (18)	C7—H7B	0.9700
N1—C13	1.458 (2)	C9—C11	1.511 (3)
O1—C5	1.3306 (17)	C9—C10	1.512 (3)
O1—C4	1.4830 (16)	C9—C12	1.516 (2)
C2—C4	1.508 (2)	C10—H10A	0.9600
C2—H2A	0.9600	C10—H10B	0.9600
C2—H2B	0.9600	C10—H10C	0.9600
C2—H2C	0.9600	C11—H11A	0.9600
O2—C5	1.1992 (17)	C11—H11B	0.9600
C3—C4	1.506 (2)	C11—H11C	0.9600
C3—H3A	0.9600	C12—H12A	0.9600
C3—H3B	0.9600	C12—H12B	0.9600
C3—H3C	0.9600	C12—H12C	0.9600
O3—C8	1.1992 (17)	C13—C14	1.504 (2)
O4—C8	1.3285 (17)	C13—H13A	0.9700
O4—C9	1.4794 (18)	C13—H13B	0.9700
C5—C6	1.505 (2)	C14—H14A	0.9700
O5—C14	1.394 (2)	C14—H14B	0.9700

C4—C1—H1A	109.5	N1—C7—H7B	108.4
C4—C1—H1B	109.5	C8—C7—H7B	108.4
H1A—C1—H1B	109.5	H7A—C7—H7B	107.4
C4—C1—H1C	109.5	O3—C8—O4	125.07 (14)
H1A—C1—H1C	109.5	O3—C8—C7	124.84 (14)
H1B—C1—H1C	109.5	O4—C8—C7	110.08 (13)
C7—N1—C6	113.32 (12)	O4—C9—C11	109.66 (14)
C7—N1—C13	113.11 (12)	O4—C9—C10	109.51 (14)
C6—N1—C13	114.57 (13)	C11—C9—C10	112.41 (17)
C5—O1—C4	121.77 (11)	O4—C9—C12	102.18 (14)
C4—C2—H2A	109.5	C11—C9—C12	111.49 (17)
C4—C2—H2B	109.5	C10—C9—C12	111.10 (17)
H2A—C2—H2B	109.5	C9—C10—H10A	109.5
C4—C2—H2C	109.5	C9—C10—H10B	109.5
H2A—C2—H2C	109.5	H10A—C10—H10B	109.5
H2B—C2—H2C	109.5	C9—C10—H10C	109.5
C4—C3—H3A	109.5	H10A—C10—H10C	109.5
C4—C3—H3B	109.5	H10B—C10—H10C	109.5
H3A—C3—H3B	109.5	C9—C11—H11A	109.5
C4—C3—H3C	109.5	C9—C11—H11B	109.5
H3A—C3—H3C	109.5	H11A—C11—H11B	109.5
H3B—C3—H3C	109.5	C9—C11—H11C	109.5
O1—C4—C3	110.86 (12)	H11A—C11—H11C	109.5
O1—C4—C1	108.31 (12)	H11B—C11—H11C	109.5
C3—C4—C1	113.35 (15)	C9—C12—H12A	109.5
O1—C4—C2	102.02 (12)	C9—C12—H12B	109.5
C3—C4—C2	110.68 (15)	H12A—C12—H12B	109.5
C1—C4—C2	111.02 (14)	C9—C12—H12C	109.5
C8—O4—C9	121.82 (12)	H12A—C12—H12C	109.5
O2—C5—O1	125.25 (13)	H12B—C12—H12C	109.5
O2—C5—C6	125.91 (13)	N1—C13—C14	112.53 (14)
O1—C5—C6	108.83 (12)	N1—C13—H13A	109.1
C14—O5—H5	106.1 (19)	C14—C13—H13A	109.1
N1—C6—C5	114.14 (12)	N1—C13—H13B	109.1
N1—C6—H6A	108.7	C14—C13—H13B	109.1
C5—C6—H6A	108.7	H13A—C13—H13B	107.8
N1—C6—H6B	108.7	O5—C14—C13	113.37 (16)
C5—C6—H6B	108.7	O5—C14—H14A	108.9
H6A—C6—H6B	107.6	C13—C14—H14A	108.9
N1—C7—C8	115.57 (13)	O5—C14—H14B	108.9
N1—C7—H7A	108.4	C13—C14—H14B	108.9
C8—C7—H7A	108.4	H14A—C14—H14B	107.7

C5—O1—C4—C3	62.24 (18)	C9—O4—C8—O3	2.7 (2)
C5—O1—C4—C1	−62.70 (17)	C9—O4—C8—C7	−176.42 (14)
C5—O1—C4—C2	−179.88 (14)	N1—C7—C8—O3	−1.9 (2)
C4—O1—C5—O2	−10.4 (2)	N1—C7—C8—O4	177.19 (13)
C4—O1—C5—C6	168.74 (12)	C8—O4—C9—C11	−63.4 (2)
C7—N1—C6—C5	−132.21 (13)	C8—O4—C9—C10	60.4 (2)
C13—N1—C6—C5	95.96 (16)	C8—O4—C9—C12	178.25 (16)
O2—C5—C6—N1	−3.5 (2)	C7—N1—C13—C14	156.64 (14)
O1—C5—C6—N1	177.39 (12)	C6—N1—C13—C14	−71.43 (18)
C6—N1—C7—C8	−62.21 (18)	N1—C13—C14—O5	−57.2 (2)
C13—N1—C7—C8	70.33 (18)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5···O2	0.85 (1)	2.13 (2)	2.8658 (18)	145 (2)

Experimental details

Crystal data
Chemical formula	C₁₄H₂₇NO₅
M_r	289.37
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	296
a, b, c (Å)	11.9767 (4), 9.7187 (3), 29.3476 (7)
V (Å³)	3416.00 (18)
Z	8
Radiation type	Mo Kα
µ (mm⁻¹)	0.08
Crystal size (mm)	0.36 × 0.21 × 0.08

Data collection
Diffractometer	Bruker SMART APEX CCD area-detector diffractometer
Absorption correction	Multi-scan (SADABS; Bruker, 2007)
T_min, T_max	0.970, 0.993
No. of measured, independent and observed [I > 2σ(I)] reflections	12339, 3958, 2503
R_int	0.022
(sin θ/λ)_max (Å⁻¹)	0.652

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.046, 0.128, 1.02
No. of reflections	3958
No. of parameters	190
No. of restraints	1
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.13, −0.17

Computer programs: SMART (Bruker, 1998), SAINT (Bruker, 1998), SAINT (Bruker, 2005), SHELXTL (Sheldrick, 2008).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
O5—H5···O2	0.848 (10)	2.128 (17)	2.8658 (18)	145 (2)

Acknowledgements

This work was supported by the Natural Science Foundation of China (No. 20671013) and the National Basic Research Program of China (No. 2006CB500705).

References

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