(E)-2-Styryl-[1,3,6,2]­diox­aza­borolane

In the title compound, C₁₂H₁₆BNO₂, the B—N distance is 1.662 (4) Å. Molecules are linked through intermolecular N—H...O hydrogen bonds to form infinite chains with an N...O distance of 2.810 (2) Å.

Key indicators

• Single-crystal X-ray study
• T = 150 K
• Mean [sigma](C-C) = 0.003 Å
• R factor = 0.030
• wR factor = 0.080
• Data-to-parameter ratio = 8.4

checkCIF results

No syntax errors found

ADDSYM reports no extra symmetry

General Notes



REFLT_03
         From the CIF: _diffrn_reflns_theta_max           26.36
         From the CIF: _reflns_number_total               1259
         Count of symmetry unique reflns         1267
         Completeness (_total/calc)             99.37%
         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
          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.

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S1. Comment

The title compound (I) shows high reactivity in rhodium(I)-catalysed 1,4-additions to α,β-unsaturated carbonyl compounds and additions to aldehydes (see Scheme below) (Batey & Smil, 2001). Use of (E)-2-phenyl-1-ethenylboronic acid, along with other aryl- and alkenylboronic acids, in 1,4-additions to α,β-unsaturated carbonyl compounds (Sakai et al., 1997) and additions to aldehydes (Sakai et al., 1998) has been reported, but the additional stability of diethanolamine boronate (I) to air and water makes its preparation, isolation, storage and handling more facile.

The structure of (I) is similar to that of the compounds 4,5,7,8-tetrahydro-2-(2-propenyl)-6H-[1,3,6,2]-dioxazaborocine (II) (Thadani et al., 2001a) and 2-(2-cyclohex-1-enylvinyl)-[1,3,6,2] dioxazaborocane (III) (Thadani et al., 2001b) which we have already determined. Molecules of (I) are linked by hydrogen bonds to form infinite chains through 2₁ screw axes in the y direction. The N···O distance in (I) is 2.810 (2) Å for N1.·O1 (see Fig. 2 and Table 2). The B1—N1 distance is 1.662 (4) Å in (I), 1.6720 (17) Å in (II) and 1.659 (4) Å in (III). A list of references for other dioxazaborocine compounds is included in our earlier paper (Thadani et al., 2001a).

S2. Experimental

Crystals of (I) were obtained by treatment of (E)-2-phenyl-1-ethenylboronic acid dissolved in minimal amount of 2-propanol with diethanolamine (1 equiv.). The mixture was stirred for 2 h at 298 K prior to collection of the precipitate by filtration. Recrystallization of the solid from acetonitrile gave (I) in 69% yield.

S3. Refinement

Hydrogen atoms were included in calculated positions with C—H distances ranging from 0.95 to 0.99 Å, and the H atom to the N was refined with an isotropic thermal parameter.

Computing details

Data collection: COLLECT (Nonius, 1997–2001); cell refinement: DENZO SMN (Otwinowski & Minor, 1997); data reduction: DENZO SMN; program(s) used to solve structure: SHELXTL/PC (Sheldrick, 2001); program(s) used to refine structure: SHELXTL/PC; molecular graphics: SHELXTL/PC; software used to prepare material for publication: SHELXTL/PC.

Figures

	Fig. 1. View of (I) showing labelling scheme. Ellipsoids are drawn at the 50% probability level.
	Fig. 2. View of the hydrogen bonding in (I) showing infinite chains in the z direction. Ellipsoids are drawn at the 50% probability level.

(E)-2-Styryl-[1,3,6,2]dioxazaborolane

Crystal data

C12H16BNO2	Dx = 1.246 Mg m^−3
Mr = 217.07	Mo Kα radiation, λ = 0.71073 Å
Orthorhombic, Pca21	Cell parameters from 8659 reflections
a = 13.3725 (4) Å	θ = 4.2–26.4°
b = 9.7045 (3) Å	µ = 0.08 mm^−1
c = 8.9200 (2) Å	T = 150 K
V = 1157.58 (6) Å^3	Needle, colourless
Z = 4	0.43 × 0.25 × 0.15 mm
F(000) = 464

Data collection

Nonius Kappa-CCD diffractometer	1167 reflections with I > 2σ(I)
Radiation source: fine-focus sealed tube	Rint = 0.037
Graphite monochromator	θmax = 26.4°, θmin = 4.2°
Detector resolution: 9 pixels mm^-1	h = −16→16
ϕ scans and ω scans with κ offsets	k = −12→12
8659 measured reflections	l = −11→11
1259 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 atoms treated by a mixture of independent and constrained refinement
wR(F^2) = 0.080	w = 1/[σ^2(Fo^2) + (0.0467P)^2 + 0.1149P] where P = (Fo^2 + 2Fc^2)/3
S = 1.08	(Δ/σ)max = 0.001
1259 reflections	Δρmax = 0.16 e Å^−3
150 parameters	Δρmin = −0.14 e Å^−3
1 restraint	Extinction correction: SHELXL, Fc^*=kFc[1+0.001xFc^2λ^3/sin(2θ)]^-1/4
Primary atom site location: structure-invariant direct methods	Extinction coefficient: 0.026 (6)

Special details

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 (Ų)

	x	y	z	Uiso*/Ueq
O1	0.36568 (9)	0.02575 (12)	0.57885 (15)	0.0287 (3)
O2	0.54825 (9)	0.03601 (13)	0.57204 (15)	0.0280 (3)
N1	0.45858 (10)	−0.09011 (15)	0.38133 (16)	0.0222 (3)
C1	0.44798 (13)	0.18667 (18)	0.3898 (2)	0.0250 (4)
H1A	0.5097	0.2278	0.3620	0.030*
C2	0.36498 (13)	0.24859 (19)	0.3429 (2)	0.0302 (4)
H2A	0.3035	0.2098	0.3755	0.036*
C3	0.35828 (15)	0.37126 (18)	0.2457 (2)	0.0303 (4)
C4	0.26994 (16)	0.3983 (2)	0.1683 (3)	0.0415 (5)
H4A	0.2141	0.3391	0.1817	0.050*
C5	0.26187 (18)	0.5101 (2)	0.0720 (3)	0.0465 (5)
H5A	0.2013	0.5261	0.0191	0.056*
C6	0.34207 (17)	0.5978 (2)	0.0531 (3)	0.0416 (5)
H6A	0.3366	0.6751	−0.0118	0.050*
C7	0.43061 (17)	0.57307 (19)	0.1291 (2)	0.0381 (5)
H7A	0.4860	0.6332	0.1158	0.046*
C8	0.43859 (15)	0.46087 (18)	0.2244 (2)	0.0321 (4)
H8A	0.4996	0.4447	0.2759	0.039*
C9	0.34381 (13)	−0.11719 (19)	0.5789 (2)	0.0304 (4)
H9A	0.2728	−0.1334	0.6051	0.036*
H9B	0.3866	−0.1665	0.6519	0.036*
C10	0.36543 (13)	−0.16522 (19)	0.4206 (2)	0.0298 (4)
H10A	0.3759	−0.2662	0.4172	0.036*
H10B	0.3102	−0.1404	0.3519	0.036*
C11	0.61617 (13)	−0.0472 (2)	0.4910 (2)	0.0306 (4)
H11A	0.6678	−0.0859	0.5585	0.037*
H11B	0.6496	0.0070	0.4114	0.037*
C12	0.55287 (13)	−0.16096 (19)	0.4235 (2)	0.0305 (4)
H12A	0.5859	−0.2014	0.3344	0.037*
H12B	0.5401	−0.2348	0.4976	0.037*
B1	0.45355 (13)	0.05011 (19)	0.4881 (2)	0.0232 (4)
H1N	0.4571 (17)	−0.069 (2)	0.290 (3)	0.037 (6)*

Atomic displacement parameters (Ų)

	U^11	U^22	U^33	U^12	U^13	U^23
O1	0.0308 (6)	0.0325 (7)	0.0227 (6)	0.0010 (5)	0.0059 (6)	−0.0003 (6)
O2	0.0284 (6)	0.0344 (7)	0.0210 (7)	0.0015 (5)	−0.0038 (5)	−0.0017 (5)
N1	0.0246 (7)	0.0261 (7)	0.0160 (7)	0.0005 (6)	0.0000 (6)	0.0010 (6)
C1	0.0293 (8)	0.0264 (8)	0.0195 (8)	−0.0024 (6)	0.0014 (7)	−0.0025 (7)
C2	0.0305 (8)	0.0294 (9)	0.0306 (9)	−0.0011 (7)	0.0008 (8)	0.0034 (8)
C3	0.0341 (9)	0.0291 (9)	0.0277 (9)	0.0018 (7)	0.0008 (7)	0.0007 (8)
C4	0.0367 (10)	0.0395 (10)	0.0485 (13)	0.0003 (8)	−0.0041 (9)	0.0114 (10)
C5	0.0428 (11)	0.0464 (11)	0.0503 (13)	0.0072 (9)	−0.0081 (12)	0.0135 (11)
C6	0.0556 (13)	0.0304 (9)	0.0387 (11)	0.0073 (9)	0.0034 (10)	0.0099 (9)
C7	0.0469 (11)	0.0303 (10)	0.0372 (12)	−0.0030 (8)	0.0030 (9)	0.0037 (8)
C8	0.0377 (10)	0.0299 (9)	0.0287 (9)	−0.0011 (7)	−0.0008 (8)	0.0010 (7)
C9	0.0291 (9)	0.0369 (10)	0.0250 (9)	−0.0037 (7)	0.0017 (8)	0.0044 (8)
C10	0.0293 (9)	0.0346 (10)	0.0255 (9)	−0.0069 (8)	0.0001 (8)	0.0005 (8)
C11	0.0233 (8)	0.0424 (11)	0.0262 (9)	0.0018 (7)	0.0014 (8)	0.0014 (8)
C12	0.0294 (9)	0.0322 (9)	0.0297 (10)	0.0072 (7)	−0.0003 (8)	−0.0005 (8)
B1	0.0264 (9)	0.0270 (10)	0.0161 (9)	0.0006 (7)	−0.0008 (8)	−0.0029 (8)

Geometric parameters (Å, º)

O1—C9	1.418 (2)	C5—C6	1.380 (3)
O1—B1	1.446 (2)	C5—H5A	0.9500
O2—C11	1.414 (2)	C6—C7	1.385 (3)
O2—B1	1.477 (2)	C6—H6A	0.9500
N1—C12	1.485 (2)	C7—C8	1.385 (3)
N1—C10	1.485 (2)	C7—H7A	0.9500
N1—B1	1.663 (2)	C8—H8A	0.9500
N1—H1N	0.84 (3)	C9—C10	1.515 (3)
C1—C2	1.330 (2)	C9—H9A	0.9900
C1—B1	1.591 (3)	C9—H9B	0.9900
C1—H1A	0.9500	C10—H10A	0.9900
C2—C3	1.476 (3)	C10—H10B	0.9900
C2—H2A	0.9500	C11—C12	1.516 (3)
C3—C4	1.393 (3)	C11—H11A	0.9900
C3—C8	1.395 (3)	C11—H11B	0.9900
C4—C5	1.387 (3)	C12—H12A	0.9900
C4—H4A	0.9500	C12—H12B	0.9900
C9—O1—B1	109.14 (13)	C3—C8—H8A	119.5
C11—O2—B1	110.16 (14)	O1—C9—C10	105.15 (15)
C12—N1—C10	115.16 (14)	O1—C9—H9A	110.7
C12—N1—B1	105.55 (13)	C10—C9—H9A	110.7
C10—N1—B1	103.44 (13)	O1—C9—H9B	110.7
C12—N1—H1N	112.3 (16)	C10—C9—H9B	110.7
C10—N1—H1N	109.3 (16)	H9A—C9—H9B	108.8
B1—N1—H1N	110.5 (15)	N1—C10—C9	103.24 (14)
C2—C1—B1	126.08 (16)	N1—C10—H10A	111.1
C2—C1—H1A	117.0	C9—C10—H10A	111.1
B1—C1—H1A	117.0	N1—C10—H10B	111.1
C1—C2—C3	126.88 (17)	C9—C10—H10B	111.1
C1—C2—H2A	116.6	H10A—C10—H10B	109.1
C3—C2—H2A	116.6	O2—C11—C12	105.08 (13)
C4—C3—C8	117.87 (17)	O2—C11—H11A	110.7
C4—C3—C2	119.67 (17)	C12—C11—H11A	110.7
C8—C3—C2	122.44 (18)	O2—C11—H11B	110.7
C5—C4—C3	121.35 (19)	C12—C11—H11B	110.7
C5—C4—H4A	119.3	H11A—C11—H11B	108.8
C3—C4—H4A	119.3	N1—C12—C11	103.74 (14)
C6—C5—C4	119.8 (2)	N1—C12—H12A	111.0
C6—C5—H5A	120.1	C11—C12—H12A	111.0
C4—C5—H5A	120.1	N1—C12—H12B	111.0
C5—C6—C7	119.85 (19)	C11—C12—H12B	111.0
C5—C6—H6A	120.1	H12A—C12—H12B	109.0
C7—C6—H6A	120.1	O1—B1—O2	113.45 (16)
C6—C7—C8	120.15 (19)	O1—B1—C1	113.99 (14)
C6—C7—H7A	119.9	O2—B1—C1	113.36 (14)
C8—C7—H7A	119.9	O1—B1—N1	102.69 (13)
C7—C8—C3	120.96 (19)	O2—B1—N1	100.36 (12)
C7—C8—H8A	119.5	C1—B1—N1	111.57 (15)

Hydrogen-bond geometry (Å, º)

D—H···A	D—H	H···A	D···A	D—H···A
N1—H1N···O2^i	0.84 (3)	1.97 (3)	2.810 (2)	175 (2)

Symmetry code: (i) −x+1, −y, z−1/2.