(N→B)-4-Methyl-3-pyrid­yl[N-methyl­imino­diacetate-O,O′,N]borane

Dąbrowski, M.; Durka, K.; Serwatowski, J.

doi:10.1107/S1600536812040974

organic compounds

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ISSN: 2056-9890

Volume 68| Part 11| November 2012| Page o3070

doi:10.1107/S1600536812040974

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(N→B)-4-Methyl-3-pyridyl[N-methyliminodiacetate-O,O′,N]borane

Marek Dąbrowski,^a Krzysztof Durka ^a ^* and Janusz Serwatowski ^a

^aPhysical Chemistry Department, Faculty of Chemistry, Warsaw University of, Technology, Noakowskiego 3, 00-664 Warsaw, Poland
^*Correspondence e-mail: kdurka@ch.pw.edu.pl

(Received 18 September 2012; accepted 28 September 2012; online 6 October 2012)

The title compound, C₁₁H₁₃BN₂O₄, has a rigid bicyclic structure due to an intramolecular nitrogen–boron dative bond. The B atom is in a distorted tetrahedron environment with a B—N bond length of 1.640 (2) Å, which is in good comparison with the values in analogues compounds. In the crystal, the molecules are linked by weak C—H⋯O and C—H⋯N interactions, forming a three-dimensional network.

Related literature

For related structures of [N-alkyliminodiacetate-O,O′,N]boranes, see: Mancilla et al. (1997 , 2005 ); Gillis & Burke (2008 ); Knapp et al. (2009 ); Percino et al. (2009 ).

Experimental

Crystal data

C₁₁H₁₃BN₂O₄
M_r = 248.04
Monoclinic, P 2₁ /n
a = 7.306 (3) Å
b = 14.7425 (4) Å
c = 10.8281 (19) Å
β = 96.91 (4)°
V = 1157.8 (5) Å³
Z = 4
Mo Kα radiation
μ = 0.11 mm⁻¹
T = 100 K
0.16 × 0.12 × 0.10 mm

Data collection

Agilent Xcalibur Opal diffractometer
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011 ) T_min = 0.910, T_max = 0.989
26273 measured reflections
3993 independent reflections
3148 reflections with I > 2σ(I)
R_int = 0.075

Refinement

R[F² > 2σ(F²)] = 0.052
wR(F²) = 0.147
S = 1.07
3993 reflections
163 parameters
H-atom parameters constrained
Δρ_max = 0.47 e Å⁻³
Δρ_min = −0.43 e Å⁻³

Table 1
Hydrogen-bond geometry (Å, °)

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C8—H10A⋯O4ⁱ	0.99	2.42	3.356 (1)	158
C11—H12B⋯N1ⁱⁱ	0.98	2.64	3.509 (1)	149
C11—H12A⋯O4ⁱ	0.98	2.40	3.259 (1)	146
C10—H8A⋯O3ⁱⁱⁱ	0.99	2.28	3.247 (1)	165
C11—H12C⋯O2^iv	0.98	2.57	3.500 (1)	158
Symmetry codes: (i) $[x+{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ ; (ii) x-1, y, z; (iii) -x, -y, -z+1; (iv) $[x-{\script{1\over 2}}, -y+{\script{1\over 2}}, z-{\script{1\over 2}}]$ .

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO; data reduction: CrysAlis PRO; program(s) used to solve structure: SHELXTL (Sheldrick, 2008 ); program(s) used to refine structure: SHELXTL; molecular graphics: DIAMOND (Brandenburg, 2005 ); software used to prepare material for publication: SHELXTL and PLATON (Spek, 2009 ).

Supporting information

Crystal structure: contains datablocks global, I. DOI: 10.1107/S1600536812040974/is5196sup1.cif

Structure factors: contains datablock I. DOI: 10.1107/S1600536812040974/is5196Isup2.hkl

checkCIF report

Comment top

Boron heterocycles derived from amino acids have received considerable attention due to their utilization in organic synthesis and medicine. Boronic acids that are susceptible to degradations are protected with N-methyliminodiacetic acid (MIDA) ligand. The MIDA boronates are compatible with a wide range of common synthetic reagents, allowing them to be functionalized to create complex boronic acid derivatives (Mancilla et al., 1997, 2005; Gillis et al., 2008; Knapp et al., 2009; Percino et al., 2009). Our interest has focused on the MIDA esters of pyridineboronic acids and their structural behavior.

In the title compound, the boron atom has a tetrahedral geometry with bond angles at the B atom ranging from 99.1 (2) to 116.8 (1)°. The B—O [1.466 (2) and 1.489 (2) Å] and B—C [1.595 (2) Å] bond lengths are in the normal ranges for such compounds. The B—N bond length is equal to 1.640 (2) Å and is similar to the values found in the other structures of MIDA boronate esters. As indicated by the C1—B1—N2—C11 and C2—C2—B1—O1 torsion angles, the bicycle ring is significantly distorted and the aryl unit is twisted along C—B bond. The crystal structure is dominated by weak C—H···O and C—H···N hydrogen interactions (Table 1).

Related literature top

For related structures of [N-alkyliminodiacetate-O,O',N]boranes, see: Mancilla et al. (1997, 2005); Gillis et al. (2008); Knapp et al. (2009); Percino et al. (2009).

Experimental top

The title compound was received from Aldrich. Single crystals suitable for X-ray diffraction analysis were grown by cooling a solution of the ester (0.2 g) in diethyl ether (10 ml) and dimethyl sulfoxide (5 ml).

Computing details top

Data collection: CrysAlis PRO (Agilent, 2011); cell refinement: CrysAlis PRO (Agilent, 2011); data reduction: CrysAlis PRO (Agilent, 2011); program(s) used to solve structure: SHELXTL (Sheldrick, 2008); program(s) used to refine structure: SHELXTL (Sheldrick, 2008); molecular graphics: DIAMOND (Brandenburg, 2005); software used to prepare material for publication: SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Figures top

	Fig. 1. The molecular structure of the title compound with the atom numbering scheme. Displacement ellipsoids for non-H atoms are drawn at the 50% probability level.
	Fig. 2. A packing diagram of the title compound, viewed along the a axis.

(N→B)-4-Methyl-3-pyridyl[N- methyliminodiacetate-O,O',N]borane top

Crystal data top

C₁₁H₁₃BN₂O₄	F(000) = 520
M_r = 248.04	D_x = 1.423 Mg m⁻³
Monoclinic, P2₁/n	Mo Kα radiation, λ = 0.7107 Å
Hall symbol: -P 2yn	Cell parameters from 9561 reflections
a = 7.306 (3) Å	θ = 1.9–32.2°
b = 14.7425 (4) Å	µ = 0.11 mm⁻¹
c = 10.8281 (19) Å	T = 100 K
β = 96.91 (4)°	Unshaped, colourless
V = 1157.8 (5) Å³	0.16 × 0.12 × 0.10 mm
Z = 4

Data collection top

Agilent Xcalibur Opal diffractometer	3993 independent reflections
Radiation source: Enhance (Mo) X-ray Source	3148 reflections with I > 2σ(I)
Graphite monochromator	R_int = 0.075
Detector resolution: 8.4441 pixels mm^-1	θ_max = 32.3°, θ_min = 2.3°
ω scan	h = −10→10
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011)	k = −21→21
T_min = 0.910, T_max = 0.989	l = −16→16
26273 measured reflections

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)] = 0.052	Hydrogen site location: inferred from neighbouring sites
wR(F²) = 0.147	H-atom parameters constrained
S = 1.07	w = 1/[σ²(F_o²) + (0.0715P)² + 0.4349P] where P = (F_o² + 2F_c²)/3
3993 reflections	(Δ/σ)_max < 0.001
163 parameters	Δρ_max = 0.47 e Å⁻³
0 restraints	Δρ_min = −0.43 e Å⁻³

Crystal data top

C₁₁H₁₃BN₂O₄	V = 1157.8 (5) Å³
M_r = 248.04	Z = 4
Monoclinic, P2₁/n	Mo Kα radiation
a = 7.306 (3) Å	µ = 0.11 mm⁻¹
b = 14.7425 (4) Å	T = 100 K
c = 10.8281 (19) Å	0.16 × 0.12 × 0.10 mm
β = 96.91 (4)°

Data collection top

Agilent Xcalibur Opal diffractometer	3993 independent reflections
Absorption correction: multi-scan (CrysAlis PRO; Agilent, 2011)	3148 reflections with I > 2σ(I)
T_min = 0.910, T_max = 0.989	R_int = 0.075
26273 measured reflections

Refinement top

R[F² > 2σ(F²)] = 0.052	0 restraints
wR(F²) = 0.147	H-atom parameters constrained
S = 1.07	Δρ_max = 0.47 e Å⁻³
3993 reflections	Δρ_min = −0.43 e Å⁻³
163 parameters

Special details top

Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s 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 > σ(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
C11	−0.2305 (2)	0.29350 (10)	0.44416 (12)	0.0241 (3)
H12A	−0.1311	0.3273	0.4117	0.036*
H12B	−0.2901	0.3322	0.5011	0.036*
H12C	−0.3216	0.2748	0.3750	0.036*
O1	0.10475 (13)	0.14926 (6)	0.64076 (9)	0.0195 (2)
O2	−0.13312 (13)	0.22847 (6)	0.73583 (8)	0.0196 (2)
N2	−0.15248 (15)	0.21153 (7)	0.51222 (9)	0.0157 (2)
C2	0.11011 (17)	0.32272 (8)	0.63785 (11)	0.0167 (2)
O3	0.20124 (15)	0.04826 (7)	0.50831 (11)	0.0275 (2)
O4	−0.41001 (16)	0.17271 (7)	0.76432 (11)	0.0305 (3)
C8	−0.04008 (19)	0.15473 (9)	0.43621 (12)	0.0198 (3)
H10A	0.0208	0.1927	0.3777	0.024*
H10B	−0.1177	0.1087	0.3882	0.024*
C3	0.06232 (18)	0.40943 (9)	0.67863 (12)	0.0188 (2)
C9	−0.29166 (19)	0.18660 (8)	0.69872 (12)	0.0199 (3)
B1	−0.01072 (19)	0.23263 (9)	0.63818 (12)	0.0157 (2)
C10	−0.30028 (19)	0.15837 (9)	0.56364 (13)	0.0213 (3)
H8A	−0.2776	0.0925	0.5570	0.026*
H8B	−0.4226	0.1727	0.5181	0.026*
C4	0.1896 (2)	0.47963 (9)	0.67544 (13)	0.0228 (3)
H4	0.1618	0.5384	0.7041	0.027*
C7	0.10090 (18)	0.11005 (8)	0.53041 (12)	0.0189 (2)
C1	0.28286 (19)	0.31591 (10)	0.59509 (14)	0.0246 (3)
H1	0.3165	0.2579	0.5669	0.029*
N1	0.40557 (18)	0.38297 (9)	0.58999 (14)	0.0305 (3)
C6	−0.1176 (2)	0.43051 (10)	0.72727 (17)	0.0310 (3)
H6A	−0.1941	0.3757	0.7236	0.046*
H6B	−0.1825	0.4781	0.6762	0.046*
H6C	−0.0934	0.4514	0.8136	0.046*
C5	0.3558 (2)	0.46393 (10)	0.63083 (15)	0.0274 (3)
H5	0.4393	0.5132	0.6290	0.033*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
C11	0.0284 (7)	0.0246 (6)	0.0183 (6)	0.0100 (5)	−0.0018 (5)	0.0020 (5)
O1	0.0217 (5)	0.0160 (4)	0.0201 (4)	0.0042 (3)	−0.0009 (3)	0.0005 (3)
O2	0.0235 (5)	0.0203 (4)	0.0153 (4)	−0.0028 (3)	0.0043 (3)	−0.0011 (3)
N2	0.0161 (5)	0.0157 (4)	0.0153 (4)	0.0022 (4)	0.0014 (4)	−0.0016 (3)
C2	0.0160 (5)	0.0167 (5)	0.0173 (5)	0.0009 (4)	0.0016 (4)	−0.0001 (4)
O3	0.0270 (5)	0.0197 (5)	0.0372 (6)	0.0076 (4)	0.0092 (4)	−0.0022 (4)
O4	0.0326 (6)	0.0271 (5)	0.0355 (6)	−0.0047 (4)	0.0198 (5)	−0.0006 (4)
C8	0.0228 (6)	0.0207 (6)	0.0164 (5)	0.0042 (5)	0.0043 (4)	−0.0027 (4)
C3	0.0192 (6)	0.0171 (5)	0.0201 (5)	0.0006 (4)	0.0030 (4)	−0.0009 (4)
C9	0.0227 (6)	0.0147 (5)	0.0234 (6)	0.0006 (4)	0.0080 (5)	−0.0012 (4)
B1	0.0172 (6)	0.0152 (6)	0.0144 (5)	0.0016 (5)	0.0010 (5)	−0.0007 (4)
C10	0.0186 (6)	0.0204 (6)	0.0257 (6)	−0.0026 (5)	0.0052 (5)	−0.0057 (5)
C4	0.0261 (7)	0.0155 (5)	0.0268 (6)	−0.0019 (5)	0.0030 (5)	0.0003 (5)
C7	0.0195 (6)	0.0148 (5)	0.0231 (6)	0.0007 (4)	0.0053 (5)	0.0001 (4)
C1	0.0192 (6)	0.0231 (6)	0.0325 (7)	−0.0002 (5)	0.0079 (5)	−0.0049 (5)
N1	0.0219 (6)	0.0286 (6)	0.0431 (7)	−0.0049 (5)	0.0120 (5)	−0.0048 (5)
C6	0.0267 (7)	0.0213 (6)	0.0475 (9)	0.0007 (5)	0.0155 (7)	−0.0108 (6)
C5	0.0254 (7)	0.0232 (6)	0.0344 (7)	−0.0073 (5)	0.0062 (6)	0.0010 (5)

Geometric parameters (Å, º) top

C11—N2	1.4924 (17)	C8—H10A	0.9900
C11—H12A	0.9800	C8—H10B	0.9900
C11—H12B	0.9800	C3—C4	1.3947 (18)
C11—H12C	0.9800	C3—C6	1.506 (2)
O1—C7	1.3246 (16)	C9—C10	1.5147 (19)
O1—B1	1.4891 (16)	C10—H8A	0.9900
O2—C9	1.3313 (17)	C10—H8B	0.9900
O2—B1	1.4660 (17)	C4—C5	1.379 (2)
N2—C8	1.4884 (16)	C4—H4	0.9500
N2—C10	1.4950 (18)	C1—N1	1.3403 (19)
N2—B1	1.6400 (19)	C1—H1	0.9500
C2—C1	1.3993 (19)	N1—C5	1.338 (2)
C2—C3	1.4101 (17)	C6—H6A	0.9800
C2—B1	1.5950 (19)	C6—H6B	0.9800
O3—C7	1.2111 (16)	C6—H6C	0.9800
O4—C9	1.2009 (17)	C5—H5	0.9500
C8—C7	1.511 (2)

N2—C11—H12A	109.5	O2—B1—C2	114.98 (10)
N2—C11—H12B	109.5	O1—B1—C2	112.01 (11)
H12A—C11—H12B	109.5	O2—B1—N2	102.29 (10)
N2—C11—H12C	109.5	O1—B1—N2	99.13 (9)
H12A—C11—H12C	109.5	C2—B1—N2	116.77 (10)
H12B—C11—H12C	109.5	N2—C10—C9	105.53 (10)
C7—O1—B1	113.13 (10)	N2—C10—H8A	110.6
C9—O2—B1	112.70 (10)	C9—C10—H8A	110.6
C8—N2—C11	112.70 (10)	N2—C10—H8B	110.6
C8—N2—C10	112.48 (10)	C9—C10—H8B	110.6
C11—N2—C10	110.99 (11)	H8A—C10—H8B	108.8
C8—N2—B1	103.37 (10)	C5—C4—C3	120.13 (13)
C11—N2—B1	115.00 (10)	C5—C4—H4	119.9
C10—N2—B1	101.65 (9)	C3—C4—H4	119.9
C1—C2—C3	115.84 (12)	O3—C7—O1	123.98 (13)
C1—C2—B1	117.55 (11)	O3—C7—C8	125.05 (12)
C3—C2—B1	126.60 (11)	O1—C7—C8	110.94 (11)
N2—C8—C7	104.40 (10)	N1—C1—C2	126.53 (13)
N2—C8—H10A	110.9	N1—C1—H1	116.7
C7—C8—H10A	110.9	C2—C1—H1	116.7
N2—C8—H10B	110.9	C5—N1—C1	115.76 (13)
C7—C8—H10B	110.9	C3—C6—H6A	109.5
H10A—C8—H10B	108.9	C3—C6—H6B	109.5
C4—C3—C2	118.29 (12)	H6A—C6—H6B	109.5
C4—C3—C6	117.93 (12)	C3—C6—H6C	109.5
C2—C3—C6	123.78 (12)	H6A—C6—H6C	109.5
O4—C9—O2	124.26 (13)	H6B—C6—H6C	109.5
O4—C9—C10	125.11 (13)	N1—C5—C4	123.44 (13)
O2—C9—C10	110.63 (11)	N1—C5—H5	118.3
O2—B1—O1	110.20 (10)	C4—C5—H5	118.3

C11—N2—C8—C7	150.72 (11)	C10—N2—B1—O2	−25.44 (11)
C10—N2—C8—C7	−82.89 (13)	C8—N2—B1—O1	−29.06 (11)
B1—N2—C8—C7	25.95 (12)	C11—N2—B1—O1	−152.32 (10)
C1—C2—C3—C4	−1.18 (19)	C10—N2—B1—O1	87.71 (11)
B1—C2—C3—C4	177.63 (12)	C8—N2—B1—C2	91.36 (12)
C1—C2—C3—C6	179.70 (14)	C11—N2—B1—C2	−31.90 (15)
B1—C2—C3—C6	−1.5 (2)	C10—N2—B1—C2	−151.87 (11)
B1—O2—C9—O4	177.44 (13)	C8—N2—C10—C9	134.54 (11)
B1—O2—C9—C10	−1.95 (15)	C11—N2—C10—C9	−98.15 (12)
C9—O2—B1—O1	−87.36 (13)	B1—N2—C10—C9	24.61 (12)
C9—O2—B1—C2	144.91 (11)	O4—C9—C10—N2	164.50 (13)
C9—O2—B1—N2	17.32 (13)	O2—C9—C10—N2	−16.11 (14)
C7—O1—B1—O2	129.43 (11)	C2—C3—C4—C5	1.3 (2)
C7—O1—B1—C2	−101.22 (12)	C6—C3—C4—C5	−179.51 (14)
C7—O1—B1—N2	22.64 (13)	B1—O1—C7—O3	170.72 (12)
C1—C2—B1—O2	149.59 (12)	B1—O1—C7—C8	−7.42 (15)
C3—C2—B1—O2	−29.19 (18)	N2—C8—C7—O3	168.47 (12)
C1—C2—B1—O1	22.78 (16)	N2—C8—C7—O1	−13.41 (14)
C3—C2—B1—O1	−156.01 (12)	C3—C2—C1—N1	0.4 (2)
C1—C2—B1—N2	−90.54 (14)	B1—C2—C1—N1	−178.55 (14)
C3—C2—B1—N2	90.67 (15)	C2—C1—N1—C5	0.4 (2)
C8—N2—B1—O2	−142.20 (10)	C1—N1—C5—C4	−0.2 (2)
C11—N2—B1—O2	94.54 (12)	C3—C4—C5—N1	−0.6 (2)

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H10A···O4ⁱ	0.99	2.42	3.356 (1)	158
C11—H12B···N1ⁱⁱ	0.98	2.64	3.509 (1)	149
C11—H12A···O4ⁱ	0.98	2.40	3.259 (1)	146
C10—H8A···O3ⁱⁱⁱ	0.99	2.28	3.247 (1)	165
C11—H12C···O2^iv	0.98	2.57	3.500 (1)	158

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

Experimental details

Crystal data
Chemical formula	C₁₁H₁₃BN₂O₄
M_r	248.04
Crystal system, space group	Monoclinic, P2₁/n
Temperature (K)	100
a, b, c (Å)	7.306 (3), 14.7425 (4), 10.8281 (19)
β (°)	96.91 (4)
V (Å³)	1157.8 (5)
Z	4
Radiation type	Mo Kα
µ (mm⁻¹)	0.11
Crystal size (mm)	0.16 × 0.12 × 0.10

Data collection
Diffractometer	Agilent Xcalibur Opal diffractometer
Absorption correction	Multi-scan (CrysAlis PRO; Agilent, 2011)
T_min, T_max	0.910, 0.989
No. of measured, independent and observed [I > 2σ(I)] reflections	26273, 3993, 3148
R_int	0.075
(sin θ/λ)_max (Å⁻¹)	0.751

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.052, 0.147, 1.07
No. of reflections	3993
No. of parameters	163
H-atom treatment	H-atom parameters constrained
Δρ_max, Δρ_min (e Å⁻³)	0.47, −0.43

Computer programs: CrysAlis PRO (Agilent, 2011), DIAMOND (Brandenburg, 2005), SHELXTL (Sheldrick, 2008) and PLATON (Spek, 2009).

Hydrogen-bond geometry (Å, º) top

D—H···A	D—H	H···A	D···A	D—H···A
C8—H10A···O4ⁱ	0.99	2.418	3.356 (1)	158
C11—H12B···N1ⁱⁱ	0.98	2.635	3.509 (1)	149
C11—H12A···O4ⁱ	0.98	2.403	3.259 (1)	146
C10—H8A···O3ⁱⁱⁱ	0.99	2.283	3.247 (1)	165
C11—H12C···O2^iv	0.98	2.574	3.500 (1)	158

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

Acknowledgements

The X-ray measurements were undertaken in the Crystallographic Unit of the Physical Chemistry Laboratory at the Chemistry Department of the University of Warsaw. This work was supported by the Aldrich Chemical Co. through donation of chemicals and equipment and by the Warsaw University of Technology.

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