Crystal structure and Hirshfield analysis of the 4-(di­methyl­amino)­pyridine adduct of 4-meth­oxy­phenyl­borane

Shooter, J.; Allen, C.J.; Tinsley, C.W.K.; Zakharov, L.N.; Abbey, E.R.

doi:10.1107/S2056989017015171

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ISSN: 2056-9890

Volume 73| Part 11| November 2017| Pages 1747-1750

https://doi.org/10.1107/S2056989017015171

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Crystal structure and Hirshfield analysis of the 4-(dimethylamino)pyridine adduct of 4-methoxyphenylborane

Jesse Shooter,^a Caleb J. Allen,^a Colby W. K. Tinsley,^a Lev N. Zakharov ^b and Eric R. Abbey ^a ^*

^aDepartment of Chemistry, Biochemistry, and Physics, Eastern Washington, University, Cheney, WA 99004, USA, and ^bDepartment of Chemistry and Biochemistry, CAMCOR, University of Oregon, Eugene, OR 97403, USA
^*Correspondence e-mail: eabbey@ewu.edu

Edited by A. J. Lough, University of Toronto, Canada (Received 9 September 2017; accepted 17 October 2017; online 20 October 2017)

The title compound [systematic name: 4-(dimethylamino)pyridine–4-methoxyphenylborane (1/1)], C₁₄H₁₉BN₂O, contains two independent molecules in the asymmetric unit. Both molecules exhibit coplanar, mostly sp²-hybridized methoxy and dimethylamino substituents on their respective aromatic rings, consistent with π-donation into the aromatic systems. The B—H groups exhibit an intramolecular close contact with a C—H group of the pyridine ring, which may be evidence of electrostatic attraction between the hydridic B—H and the electropositive aromatic C—H. There appears to be weak C—H⋯π(arene) interactions between two of the H atoms of an aminomethyl group and the methoxy-substituted benzene ring of the other independent molecule, and another C—H⋯π (arene) interaction between one of the pyridine ring H atoms and the same benzene ring.

Keywords: crystal structure; hydrogen bonding; zwitterions; Hirshfield analysis.

CCDC reference: 1580559

1. Chemical context

Monoorganoboranes (RBH₂) have been the focus of chemical research for over fifty years, most notably for their use in the indispensable hydroboration reaction, which permits reduction of olefins, carbonyl compounds and others (Brown & Krishnamurthy, 1979 ; Crudden & Edwards, 2003 .) Such boranes are often isolated as their Lewis base adducts, in which the base donates a lone pair into the vacant p orbital of the sp² borane. Among the most common class of Lewis bases for the formation of borane adducts are amines. Amine boranes are widely used as hydroboration reagents (Clay & Vedejs, 2005 ), precursors for borenium cation synthesis (De Vries et al., 2012 ), frustrated Lewis pairs (Stephan, 2015 ), and have been investigated as hydrogen-storage materials (Campbell et al., 2010 ). We have synthesized the zwitterionic title compound by hydride removal from sodium 4-methoxyphenylborohydride with chlorotrimethylsilane in the presence of 4-dimethylaminopyridine. This compound is slightly unusual, as examples of monoorganoboranes with heteroatoms on the organic substitituent are limited.

2. Structural commentary

The asymmetric unit contains two independent molecules (Figs. 1 and 2) with only slightly different geometric features (Fig. 3). In both molecules, the boron atom appears to be sp³ hybridized [C1—B1—N1 = 110.8 (1) and C1′—B1′—N1′ = 111.0 (1)°] . The B1—C1 and B1′—C1′ distances [1.608 (2) and 1.611 (2) Å, respectively] are consistent with a formal C—B single bond. The oxygen atom of both methoxy groups appears to be mostly sp² hybridized, [C7—O1—C4 = 117.3 (1) and C7′—O1′—C4′ = 117.4 (1)°] and is close to coplanar with the phenyl ring [torsion angles C7—O1—C4—C3 = −7.4 (2) and C7′—O1′—C4′—C3′ = −7.1 (2)°], consistent with π-donation into the phenyl ring.

Figure 1
The molecular structure of one of the independent molecules of the title compound with displacement ellipsoids drawn at the 50% probability level.

Figure 2
The molecular structure of the other independent molecule of the title compound with displacement ellipsoids drawn at the 50% probability level.

Figure 3
An overlay of the two independent molecules.

The geometries of the 4-(dimethylamino)pyridine (DMAP) fragment of both molecules is similar to other structures of DMAP–borane adducts. The nitrogen atom of the dimethylamino fragment appears to be sp² hybridized [torsion angles C13—N2—C10 = 121.0 (1)° and C13′—N2′—C10′ = 122.2 (1)°] and is close to coplanar [torsion angles C13—N2—C10—C11 = 2.4 (2) and C13′—N2′—C10′—C11′ = 3.4 (1)°] consistent with π-donation into the pyridine ring.

The B1—N1 and B1′—N1′ distances [1.597 (2) and 1.595 (2) Å, respectively] are consistent with formal N—B single bonds, and are within the range observed for other DMAP–borane adducts (see Database survey). Interestingly, the B—H atoms exhibit intramolecular close contacts with the C—H atoms of the pyridine ring [H12⋯H2B = 2.26 (3) and H12′⋯H2B′ = 2.27 (3) Å] and are close to coplanar [torsion angles H2B—B1—N1—C12 = 4(1) and H2B—B1—N1—C12 = 16 (1)°], which may be evidence of electrostatic interactions between the hydridic B—H atoms and electropositive aromatic C—H atoms, and is observed in other DMAP–borane adducts (see Database Survey). The planes of the pyridine rings and the benzene rings are almost normal to one another [the dihedral angle between the C1–C6 and C8–C12/N1 rings is 73.14 (7)° and that between the C1′–C6′ and C8′–C12′/N1′ rings is 74.15 (7)°]. Perhaps the most significant difference between the two molecules is the 9.0° difference in the torsion angle about the B—N bond [C1—B1—N1—C8 = −63.9 (2) while C1′—B1′—N1′—C8′ = −72.9 (2)°] (Fig. 3).

3. Supramolecular features

The molecules within the asymmetric unit exhibit weak C—H⋯π (arene) interactions between two of the hydrogen atoms of the aminomethyl group and the methoxyphenyl group of a neighboring molecule (see Table 1) as well as a C—H⋯π(arene) interaction between one of the pyridine hydrogen atoms and the same methoxyphenyl ring (Fig. 4).

Table 1
Hydrogen-bond geometry (Å, °)

Cg is the centroid of the C1′–C6′ ring.

D—H⋯A	D—H	H⋯A	D⋯A	D—H⋯A
C9—H9A⋯Cg	0.95	3.12	4.069 (2)	178
C13—H13A⋯Cg	0.97	3.12	3.662 (2)	112
C13—H13C⋯Cg	0.97	3.23	3.662 (2)	109

Figure 4
Weak C—H⋯π (arene) interactions between the two independent molecules in the unit cell shown as dashed lines. Cg is the centroid of the C1′–C6′ benzene ring. Only H atoms involved in the interactions are shown.

4. Hirshfield analysis

The weak intermolecular interactions of the title compound were explored by Hirshfield analysis. Hirshfield surfaces were generated using Crystal Explorer 3.1 (McKinnon et al., 2007 ; Spackman & Jayatilaka, 2009 ). The space within a crystal is partitioned so that the ratio of promolecule to procrystal is equal to 0.5, generating continuous surfaces that permit the visualization of weak interactions. The d_norm values illustrate whether the intermolecular contact is shorter or longer than the van der Waals radii. Red areas of the Hirshfield surface indicate negative d_norm values contacts closer than the van der Waals radii. This analysis lends further support to the weak C—H^⋯π (arene) interactions described in the previous section (Fig. 5.)

Figure 5
Hirshfield surface mapped over d_norm. Red areas highlight intermolecular contacts shorter than the sum of the van der Waals radii.

5. Database survey

A search of the Cambridge Structural Database (Version 5.37, update February 2017; Groom et al., 2016 ) for DMAP–borane adducts yielded only two structures: VOGJEI (Chu, et al., 2014 ) and JUDQAA (Lesley et al., 1998 ). A search for phenyl-based monoorganoborane–amine adducts (Ph–BH₂–NR₃) yielded four structures: UTOZEJ (Hubner et al., 2012 ), BEXQOM (Ménard & Stephan, 2013 ), EPOYAK (Franz et al., 2011 ), and GEBNAE (Jacobs et al., 2012). In all four of these structures, the B—N bonds are approximately perpendicular to the plane of the arene rings. In all six cases, the boron atom is tetrahedral and displays structural features consistent with sp³ hybridization. Additionally, the C—B and B—N bonds are all within the range for formal C—B and C—N single bonds.

6. Synthesis and crystallization

In a nitrogen-filled glove box, sodium 4-methoxyphenylborohydride (97mg, 0.67 mmol) and 4-dimethylaminopyridine (82 mg, 0.67 mmol) were combined in a 20 mL vial containing a stir bar and dissolved in anhydrous THF (4 mL). The solution was cooled to 247 K in the freezer and chlorotrimethylsilane (73 mg, 0.67 mmol) was added dropwise via syringe. The reaction was allowed to come to 295 K and was stirred for 1 h. The solvent was then removed in vacuo and the residue was washed with anhydrous diethyl ether (4 mL), followed by extraction with anhydrous dichloromethane (4 mL). The extract was filtered through a 0.45 µm PTFE syringe filter. The solvent was again removed in vacuo to afford a white solid (51 mg, 37%). Crystals suitable for X-ray diffraction were grown by diffusion of pentane into a concentrated solution of the title compound in anhydrous dichloromethane.

¹H NMR (500 MHz, CDCl₃) δ (ppm): 8.12 (d, 2H, J = 7 Hz), 7.23 (d, 2 H, J = 8 Hz), 6.80 (d, 2H, J = 8.5 Hz), 6.52 (d, 2H, J = 8 Hz), 3.78 (s, 3H), 3.11 (s, 6H). ¹³C NMR (126 MHz, CDCl₃) δ (ppm): 157.3, 154.9, 146.7, 145.0 (br s), 134.5, 122.9, 106.5, 55.0, 39.5. ¹¹B NMR (160 MHz, CDCl₃) δ (ppm): −5.0 (br, s). FTIR (ATR, cm⁻¹): 3012, 2952, 2923, 2853, 2610, 2346, 2288, 2227, 1634, 1548, 1442, 1418, 1392, 1237, 1223, 1161, 1076, 1031, 811, 797, 548, 515.

7. Refinement

Crystal data, data collection and structure refinement details are summarized in Table 2. H atoms were refined in calculated positions (C—H = 0.95 Å with U_iso(H) = 1.5U_eq(C-methyl) and 1.2eq(C) for other H atoms. The B-bound H atoms were located in a difference-Fourier map and freely refined. Methyl H atoms were refined without restrictions on rotation around the C—C bonds, HFIX 138 in SHELXL (Sheldrick, 2015 ).

Table 2
Experimental details

Crystal data
Chemical formula	C₁₄H₁₉BN₂O
M_r	242.12
Crystal system, space group	Orthorhombic, Pbca
Temperature (K)	173
a, b, c (Å)	12.3538 (6), 18.7727 (10), 23.4056 (12)
V (Å³)	5428.1 (5)
Z	16
Radiation type	Cu Kα
μ (mm⁻¹)	0.58
Crystal size (mm)	0.14 × 0.09 × 0.07

Data collection
Diffractometer	Bruker APEXII CCD
Absorption correction	Multi-scan (SADABS; Bruker, 2008 )
T_min, T_max	0.695, 0.753
No. of measured, independent and observed [I > 2σ(I)] reflections	46022, 4800, 3948
R_int	0.063
(sin θ/λ)_max (Å⁻¹)	0.595

Refinement
R[F² > 2σ(F²)], wR(F²), S	0.047, 0.144, 1.08
No. of reflections	4800
No. of parameters	353
H-atom treatment	H atoms treated by a mixture of independent and constrained refinement
Δρ_max, Δρ_min (e Å⁻³)	0.22, −0.22
Computer programs: APEX2 and SAINT (Bruker, 2008), SHELXS97 and SHELXTL (Sheldrick 2008 ), SHELXL2014 (Sheldrick, 2015) and Mercury (Macrae et al., 2008 ).

Supporting information

CCDC reference: 1580559

Crystal structure: contains datablock I. DOI: https://doi.org/10.1107/S2056989017015171/lh5853sup1.cif

Structure factors: contains datablock I. DOI: https://doi.org/10.1107/S2056989017015171/lh5853Isup2.hkl

checkCIF report

Computing details top

Data collection: APEX2 (Bruker, 2008); cell refinement: SAINT (Bruker, 2008); data reduction: SAINT (Bruker, 2008); program(s) used to solve structure: SHELXS97 (Sheldrick 2008); program(s) used to refine structure: SHELXL2014 (Sheldrick, 2015); molecular graphics: SHELXTL (Sheldrick, 2008) and Mercury (Macrae et al., 2006); software used to prepare material for publication: SHELXTL (Sheldrick, 2008).

4-(Dimethylamino)pyridine–4-methoxyphenylborane (1/1) top

Crystal data top

C₁₄H₁₉BN₂O	D_x = 1.185 Mg m⁻³
M_r = 242.12	Cu Kα radiation, λ = 1.54178 Å
Orthorhombic, Pbca	Cell parameters from 6122 reflections
a = 12.3538 (6) Å	θ = 3.8–66.5°
b = 18.7727 (10) Å	µ = 0.58 mm⁻¹
c = 23.4056 (12) Å	T = 173 K
V = 5428.1 (5) Å³	Cut-block, colorless
Z = 16	0.14 × 0.09 × 0.07 mm
F(000) = 2080

Data collection top

Bruker APEXII CCD diffractometer	3948 reflections with I > 2σ(I)
Radiation source: Incoatec IµS	R_int = 0.063
φ and ω scans	θ_max = 66.6°, θ_min = 3.8°
Absorption correction: multi-scan (SADABS; Bruker, 2008)	h = −14→14
T_min = 0.695, T_max = 0.753	k = −22→21
46022 measured reflections	l = −27→27
4800 independent reflections

Refinement top

Refinement on F²	0 restraints
Least-squares matrix: full	Hydrogen site location: mixed
R[F² > 2σ(F²)] = 0.047	H atoms treated by a mixture of independent and constrained refinement
wR(F²) = 0.144	w = 1/[σ²(F_o²) + (0.0934P)² + 0.2472P] where P = (F_o² + 2F_c²)/3
S = 1.08	(Δ/σ)_max = 0.001
4800 reflections	Δρ_max = 0.22 e Å⁻³
353 parameters	Δρ_min = −0.22 e Å⁻³

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.

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å²) top

	x	y	z	U_iso*/U_eq
B1	1.01984 (15)	0.31745 (11)	0.41477 (9)	0.0427 (4)
O1	0.94372 (10)	0.19525 (7)	0.63937 (5)	0.0486 (3)
N1	0.91495 (10)	0.31876 (7)	0.37491 (5)	0.0350 (3)
N2	0.64797 (11)	0.31846 (7)	0.26602 (6)	0.0409 (3)
C1	0.99199 (12)	0.28402 (8)	0.47629 (6)	0.0336 (3)
C2	0.88854 (12)	0.27979 (8)	0.50007 (7)	0.0349 (3)
H2A	0.8290	0.2968	0.4783	0.042*
C3	0.86858 (12)	0.25193 (8)	0.55404 (7)	0.0367 (3)
H3A	0.7969	0.2504	0.5686	0.044*
C4	0.95416 (12)	0.22634 (8)	0.58646 (6)	0.0365 (3)
C5	1.05847 (12)	0.23022 (9)	0.56465 (7)	0.0386 (4)
H5A	1.1178	0.2135	0.5867	0.046*
C6	1.07595 (12)	0.25838 (8)	0.51094 (7)	0.0364 (3)
H6A	1.1480	0.2605	0.4969	0.044*
C7	0.84022 (17)	0.19686 (13)	0.66503 (8)	0.0623 (5)
H7A	0.8163 (7)	0.2472 (7)	0.6695 (7)	0.093*
H7B	0.8437 (4)	0.1737 (9)	0.7032 (6)	0.093*
H7C	0.7877 (8)	0.1708 (9)	0.6404 (5)	0.093*
C8	0.86637 (13)	0.25774 (8)	0.35835 (7)	0.0384 (4)
H8A	0.8952	0.2140	0.3720	0.046*
C9	0.77855 (12)	0.25513 (8)	0.32330 (7)	0.0372 (3)
H9A	0.7479	0.2104	0.3133	0.045*
C10	0.73265 (12)	0.31892 (8)	0.30166 (6)	0.0331 (3)
C11	0.78395 (13)	0.38231 (8)	0.31977 (7)	0.0365 (3)
H11A	0.7572	0.4271	0.3072	0.044*
C12	0.87174 (13)	0.37956 (8)	0.35519 (6)	0.0365 (3)
H12A	0.9041	0.4232	0.3665	0.044*
C13	0.59485 (15)	0.25190 (10)	0.25018 (8)	0.0502 (4)
H13A	0.6465 (8)	0.2208 (5)	0.2318 (6)	0.075*
H13B	0.5359 (11)	0.26183 (17)	0.2242 (6)	0.075*
H13C	0.5669 (11)	0.2290 (5)	0.2841 (5)	0.075*
C14	0.60151 (17)	0.38459 (11)	0.24483 (9)	0.0582 (5)
H14A	0.5688 (13)	0.4106 (6)	0.2764 (5)	0.087*
H14B	0.5465 (13)	0.37391 (18)	0.2163 (7)	0.087*
H14C	0.6582 (9)	0.4135 (6)	0.2276 (7)	0.087*
B1'	0.69503 (16)	0.06081 (12)	0.15670 (9)	0.0453 (5)
O1'	0.60935 (10)	0.06495 (7)	0.40101 (5)	0.0465 (3)
N1'	0.59005 (11)	0.04914 (7)	0.11816 (5)	0.0376 (3)
N2'	0.31932 (10)	0.01508 (7)	0.01478 (6)	0.0381 (3)
C1'	0.66395 (12)	0.06221 (8)	0.22354 (7)	0.0353 (3)
C2'	0.55974 (13)	0.05774 (9)	0.24570 (7)	0.0390 (4)
H2'A	0.5010	0.0533	0.2197	0.047*
C3'	0.53692 (13)	0.05950 (9)	0.30416 (7)	0.0391 (4)
H3'A	0.4642	0.0567	0.3172	0.047*
C4'	0.62082 (13)	0.06528 (8)	0.34280 (7)	0.0355 (3)
C5'	0.72647 (12)	0.07031 (8)	0.32248 (7)	0.0375 (4)
H5'A	0.7850	0.0747	0.3486	0.045*
C6'	0.74621 (12)	0.06892 (8)	0.26434 (7)	0.0365 (4)
H6'A	0.8189	0.0727	0.2515	0.044*
C7'	0.50222 (15)	0.06648 (10)	0.42327 (8)	0.0505 (4)
H7'1	0.4633 (7)	0.1089 (7)	0.4080 (6)	0.076*
H7'2	0.50509 (15)	0.0693 (8)	0.4658 (6)	0.076*
H7'3	0.4632 (7)	0.0223 (7)	0.4117 (6)	0.076*
C8'	0.54070 (13)	−0.01494 (9)	0.11568 (7)	0.0389 (4)
H8'A	0.5701	−0.0528	0.1376	0.047*
C9'	0.45100 (13)	−0.02840 (8)	0.08343 (7)	0.0370 (3)
H9'A	0.4193	−0.0745	0.0839	0.044*
C10'	0.40477 (12)	0.02603 (8)	0.04920 (6)	0.0335 (3)
C11'	0.45656 (13)	0.09326 (8)	0.05317 (6)	0.0360 (3)
H11B	0.4290	0.1326	0.0322	0.043*
C12'	0.54561 (13)	0.10182 (8)	0.08691 (7)	0.0372 (3)
H12B	0.5782	0.1476	0.0885	0.045*
C13'	0.26225 (14)	−0.05283 (9)	0.01282 (8)	0.0450 (4)
H13D	0.3125 (7)	−0.0908 (5)	0.0187 (6)	0.068*
H13E	0.2285 (10)	−0.0583 (4)	−0.0236 (5)	0.068*
H13F	0.2083 (10)	−0.0539 (3)	0.0421 (5)	0.068*
C14'	0.26866 (14)	0.07399 (10)	−0.01557 (8)	0.0459 (4)
H14D	0.2354 (11)	0.1068 (6)	0.0122 (4)	0.069*
H14E	0.2125 (11)	0.0554 (2)	−0.0414 (5)	0.069*
H14F	0.3238 (7)	0.0996 (6)	−0.0380 (5)	0.069*
H1'B	0.7533 (16)	0.0147 (10)	0.1468 (8)	0.048 (5)*
H1B	1.0840 (16)	0.2841 (11)	0.3930 (8)	0.051 (5)*
H2'B	0.7314 (16)	0.1141 (10)	0.1398 (9)	0.052 (5)*
H2B	1.0475 (17)	0.3752 (11)	0.4179 (9)	0.056 (6)*

Atomic displacement parameters (Å²) top

	U¹¹	U²²	U³³	U¹²	U¹³	U²³
B1	0.0358 (9)	0.0501 (11)	0.0424 (10)	−0.0072 (8)	−0.0031 (8)	0.0077 (8)
O1	0.0447 (7)	0.0665 (8)	0.0345 (6)	0.0031 (6)	0.0016 (5)	0.0079 (5)
N1	0.0361 (7)	0.0375 (7)	0.0315 (7)	−0.0030 (5)	0.0009 (5)	0.0049 (5)
N2	0.0397 (7)	0.0423 (8)	0.0406 (7)	0.0009 (6)	−0.0056 (6)	−0.0007 (6)
C1	0.0324 (7)	0.0329 (7)	0.0354 (8)	−0.0015 (6)	−0.0026 (6)	−0.0015 (6)
C2	0.0303 (7)	0.0369 (8)	0.0375 (8)	0.0020 (6)	−0.0049 (6)	0.0006 (6)
C3	0.0290 (7)	0.0423 (8)	0.0386 (8)	0.0001 (6)	0.0019 (6)	−0.0028 (6)
C4	0.0390 (8)	0.0407 (8)	0.0298 (7)	0.0001 (6)	−0.0022 (6)	−0.0017 (6)
C5	0.0335 (8)	0.0454 (9)	0.0370 (8)	0.0026 (6)	−0.0075 (6)	0.0008 (7)
C6	0.0273 (7)	0.0431 (8)	0.0387 (8)	−0.0005 (6)	0.0005 (6)	−0.0017 (6)
C7	0.0574 (12)	0.0904 (15)	0.0391 (10)	0.0067 (10)	0.0129 (8)	0.0114 (10)
C8	0.0417 (8)	0.0327 (8)	0.0407 (8)	−0.0009 (6)	−0.0021 (7)	0.0070 (6)
C9	0.0418 (8)	0.0314 (7)	0.0385 (8)	−0.0039 (6)	−0.0003 (7)	0.0005 (6)
C10	0.0337 (7)	0.0379 (8)	0.0277 (7)	0.0013 (6)	0.0039 (6)	−0.0001 (6)
C11	0.0435 (8)	0.0324 (8)	0.0336 (8)	0.0030 (6)	0.0000 (6)	−0.0006 (6)
C12	0.0434 (8)	0.0334 (8)	0.0328 (8)	−0.0032 (6)	0.0018 (6)	0.0000 (6)
C13	0.0459 (9)	0.0540 (10)	0.0507 (10)	−0.0061 (8)	−0.0117 (8)	−0.0059 (8)
C14	0.0568 (12)	0.0560 (11)	0.0618 (12)	0.0110 (9)	−0.0197 (9)	0.0004 (9)
B1'	0.0333 (9)	0.0635 (12)	0.0392 (10)	−0.0031 (8)	0.0021 (8)	0.0000 (8)
O1'	0.0467 (7)	0.0583 (7)	0.0345 (6)	0.0036 (5)	−0.0030 (5)	−0.0021 (5)
N1'	0.0349 (7)	0.0465 (8)	0.0315 (7)	−0.0003 (5)	0.0042 (5)	−0.0018 (5)
N2'	0.0345 (7)	0.0418 (7)	0.0378 (7)	−0.0006 (5)	−0.0013 (5)	0.0025 (5)
C1'	0.0328 (8)	0.0339 (7)	0.0393 (8)	−0.0006 (6)	−0.0021 (6)	0.0000 (6)
C2'	0.0308 (8)	0.0505 (9)	0.0358 (8)	−0.0013 (6)	−0.0052 (6)	−0.0034 (7)
C3'	0.0300 (8)	0.0469 (9)	0.0403 (9)	−0.0005 (6)	0.0006 (6)	−0.0014 (7)
C4'	0.0398 (8)	0.0323 (7)	0.0345 (8)	0.0018 (6)	−0.0025 (6)	−0.0024 (6)
C5'	0.0351 (8)	0.0343 (8)	0.0431 (9)	0.0009 (6)	−0.0108 (7)	−0.0014 (6)
C6'	0.0291 (7)	0.0354 (8)	0.0449 (9)	0.0008 (6)	−0.0013 (6)	−0.0001 (6)
C7'	0.0538 (11)	0.0577 (11)	0.0399 (9)	0.0058 (8)	0.0071 (8)	−0.0059 (8)
C8'	0.0408 (8)	0.0427 (8)	0.0333 (8)	0.0051 (7)	0.0034 (6)	0.0034 (6)
C9'	0.0402 (8)	0.0365 (8)	0.0345 (8)	−0.0002 (6)	0.0049 (6)	0.0004 (6)
C10'	0.0329 (7)	0.0383 (8)	0.0292 (7)	0.0024 (6)	0.0064 (6)	−0.0022 (6)
C11'	0.0375 (8)	0.0358 (8)	0.0346 (8)	0.0037 (6)	0.0041 (6)	0.0007 (6)
C12'	0.0386 (8)	0.0375 (8)	0.0354 (8)	−0.0011 (6)	0.0067 (6)	−0.0026 (6)
C13'	0.0406 (9)	0.0491 (9)	0.0454 (9)	−0.0092 (7)	0.0018 (7)	−0.0001 (7)
C14'	0.0403 (9)	0.0520 (10)	0.0455 (10)	0.0028 (7)	−0.0049 (7)	0.0069 (7)

Geometric parameters (Å, º) top

B1—N1	1.597 (2)	B1'—N1'	1.595 (2)
B1—C1	1.608 (2)	B1'—C1'	1.611 (2)
B1—H1B	1.13 (2)	B1'—H1'B	1.150 (19)
B1—H2B	1.14 (2)	B1'—H2'B	1.166 (19)
O1—C4	1.3752 (19)	O1'—C4'	1.370 (2)
O1—C7	1.413 (2)	O1'—C7'	1.423 (2)
N1—C12	1.342 (2)	N1'—C12'	1.347 (2)
N1—C8	1.350 (2)	N1'—C8'	1.350 (2)
N2—C10	1.338 (2)	N2'—C10'	1.344 (2)
N2—C14	1.455 (2)	N2'—C14'	1.456 (2)
N2—C13	1.459 (2)	N2'—C13'	1.458 (2)
C1—C2	1.396 (2)	C1'—C2'	1.390 (2)
C1—C6	1.402 (2)	C1'—C6'	1.400 (2)
C2—C3	1.389 (2)	C2'—C3'	1.397 (2)
C2—H2A	0.9500	C2'—H2'A	0.9500
C3—C4	1.387 (2)	C3'—C4'	1.380 (2)
C3—H3A	0.9500	C3'—H3'A	0.9500
C4—C5	1.388 (2)	C4'—C5'	1.392 (2)
C5—C6	1.381 (2)	C5'—C6'	1.383 (2)
C5—H5A	0.9500	C5'—H5'A	0.9500
C6—H6A	0.9500	C6'—H6'A	0.9500
C7—H7A	0.996 (14)	C7'—H7'1	0.996 (14)
C7—H7B	0.996 (14)	C7'—H7'2	0.996 (14)
C7—H7C	0.996 (14)	C7'—H7'3	0.996 (14)
C8—C9	1.361 (2)	C8'—C9'	1.364 (2)
C8—H8A	0.9500	C8'—H8'A	0.9500
C9—C10	1.419 (2)	C9'—C10'	1.419 (2)
C9—H9A	0.9500	C9'—H9'A	0.9500
C10—C11	1.413 (2)	C10'—C11'	1.418 (2)
C11—C12	1.366 (2)	C11'—C12'	1.364 (2)
C11—H11A	0.9500	C11'—H11B	0.9500
C12—H12A	0.9500	C12'—H12B	0.9500
C13—H13A	0.967 (13)	C13'—H13D	0.955 (12)
C13—H13B	0.967 (13)	C13'—H13E	0.955 (12)
C13—H13C	0.967 (13)	C13'—H13F	0.955 (12)
C14—H14A	0.973 (15)	C14'—H14D	0.985 (12)
C14—H14B	0.973 (15)	C14'—H14E	0.985 (12)
C14—H14C	0.973 (15)	C14'—H14F	0.985 (12)

N1—B1—C1	110.83 (13)	N1'—B1'—C1'	110.96 (13)
N1—B1—H1B	108.2 (10)	N1'—B1'—H1'B	107.0 (10)
C1—B1—H1B	109.7 (10)	C1'—B1'—H1'B	110.9 (10)
N1—B1—H2B	105.5 (10)	N1'—B1'—H2'B	103.9 (10)
C1—B1—H2B	112.2 (11)	C1'—B1'—H2'B	114.0 (10)
H1B—B1—H2B	110.2 (14)	H1'B—B1'—H2'B	109.7 (14)
C4—O1—C7	117.30 (14)	C4'—O1'—C7'	117.41 (13)
C12—N1—C8	116.49 (13)	C12'—N1'—C8'	116.54 (13)
C12—N1—B1	122.47 (13)	C12'—N1'—B1'	122.52 (14)
C8—N1—B1	121.02 (13)	C8'—N1'—B1'	120.93 (14)
C10—N2—C14	121.03 (14)	C10'—N2'—C14'	120.93 (13)
C10—N2—C13	121.04 (13)	C10'—N2'—C13'	122.19 (13)
C14—N2—C13	117.81 (14)	C14'—N2'—C13'	116.18 (14)
C2—C1—C6	115.29 (14)	C2'—C1'—C6'	115.03 (14)
C2—C1—B1	125.10 (13)	C2'—C1'—B1'	125.57 (14)
C6—C1—B1	119.59 (14)	C6'—C1'—B1'	119.39 (14)
C3—C2—C1	123.11 (14)	C1'—C2'—C3'	123.40 (15)
C3—C2—H2A	118.4	C1'—C2'—H2'A	118.3
C1—C2—H2A	118.4	C3'—C2'—H2'A	118.3
C4—C3—C2	119.50 (14)	C4'—C3'—C2'	119.48 (15)
C4—C3—H3A	120.2	C4'—C3'—H3'A	120.3
C2—C3—H3A	120.2	C2'—C3'—H3'A	120.3
O1—C4—C3	124.62 (14)	O1'—C4'—C3'	125.02 (15)
O1—C4—C5	116.14 (14)	O1'—C4'—C5'	115.90 (14)
C3—C4—C5	119.23 (14)	C3'—C4'—C5'	119.06 (15)
C6—C5—C4	120.01 (14)	C6'—C5'—C4'	120.00 (14)
C6—C5—H5A	120.0	C6'—C5'—H5'A	120.0
C4—C5—H5A	120.0	C4'—C5'—H5'A	120.0
C5—C6—C1	122.85 (14)	C5'—C6'—C1'	123.02 (14)
C5—C6—H6A	118.6	C5'—C6'—H6'A	118.5
C1—C6—H6A	118.6	C1'—C6'—H6'A	118.5
O1—C7—H7A	109.5	O1'—C7'—H7'1	109.5
O1—C7—H7B	109.5	O1'—C7'—H7'2	109.5
H7A—C7—H7B	109.5	H7'1—C7'—H7'2	109.5
O1—C7—H7C	109.5	O1'—C7'—H7'3	109.5
H7A—C7—H7C	109.5	H7'1—C7'—H7'3	109.5
H7B—C7—H7C	109.5	H7'2—C7'—H7'3	109.5
N1—C8—C9	123.92 (14)	N1'—C8'—C9'	123.76 (14)
N1—C8—H8A	118.0	N1'—C8'—H8'A	118.1
C9—C8—H8A	118.0	C9'—C8'—H8'A	118.1
C8—C9—C10	120.23 (14)	C8'—C9'—C10'	120.40 (14)
C8—C9—H9A	119.9	C8'—C9'—H9'A	119.8
C10—C9—H9A	119.9	C10'—C9'—H9'A	119.8
N2—C10—C11	122.89 (14)	N2'—C10'—C9'	123.00 (14)
N2—C10—C9	121.99 (14)	N2'—C10'—C11'	122.00 (14)
C11—C10—C9	115.11 (14)	C9'—C10'—C11'	114.99 (14)
C12—C11—C10	120.41 (14)	C12'—C11'—C10'	120.44 (14)
C12—C11—H11A	119.8	C12'—C11'—H11B	119.8
C10—C11—H11A	119.8	C10'—C11'—H11B	119.8
N1—C12—C11	123.83 (14)	N1'—C12'—C11'	123.83 (14)
N1—C12—H12A	118.1	N1'—C12'—H12B	118.1
C11—C12—H12A	118.1	C11'—C12'—H12B	118.1
N2—C13—H13A	109.5	N2'—C13'—H13D	109.5
N2—C13—H13B	109.5	N2'—C13'—H13E	109.5
H13A—C13—H13B	109.5	H13D—C13'—H13E	109.5
N2—C13—H13C	109.5	N2'—C13'—H13F	109.5
H13A—C13—H13C	109.5	H13D—C13'—H13F	109.5
H13B—C13—H13C	109.5	H13E—C13'—H13F	109.5
N2—C14—H14A	109.5	N2'—C14'—H14D	109.5
N2—C14—H14B	109.5	N2'—C14'—H14E	109.5
H14A—C14—H14B	109.5	H14D—C14'—H14E	109.5
N2—C14—H14C	109.5	N2'—C14'—H14F	109.5
H14A—C14—H14C	109.5	H14D—C14'—H14F	109.5
H14B—C14—H14C	109.5	H14E—C14'—H14F	109.5

C1—B1—N1—C12	117.49 (16)	C1'—B1'—N1'—C12'	106.68 (17)
C1—B1—N1—C8	−63.9 (2)	C1'—B1'—N1'—C8'	−72.92 (19)
N1—B1—C1—C2	−21.1 (2)	N1'—B1'—C1'—C2'	−3.2 (2)
N1—B1—C1—C6	160.91 (14)	N1'—B1'—C1'—C6'	177.29 (14)
C6—C1—C2—C3	−0.4 (2)	C6'—C1'—C2'—C3'	−0.2 (2)
B1—C1—C2—C3	−178.43 (15)	B1'—C1'—C2'—C3'	−179.71 (16)
C1—C2—C3—C4	−0.5 (2)	C1'—C2'—C3'—C4'	−0.6 (3)
C7—O1—C4—C3	−7.4 (2)	C7'—O1'—C4'—C3'	−7.1 (2)
C7—O1—C4—C5	173.96 (17)	C7'—O1'—C4'—C5'	174.38 (14)
C2—C3—C4—O1	−177.46 (15)	C2'—C3'—C4'—O1'	−177.51 (15)
C2—C3—C4—C5	1.1 (2)	C2'—C3'—C4'—C5'	1.0 (2)
O1—C4—C5—C6	177.77 (14)	O1'—C4'—C5'—C6'	178.10 (13)
C3—C4—C5—C6	−0.9 (2)	C3'—C4'—C5'—C6'	−0.5 (2)
C4—C5—C6—C1	0.1 (2)	C4'—C5'—C6'—C1'	−0.3 (2)
C2—C1—C6—C5	0.6 (2)	C2'—C1'—C6'—C5'	0.6 (2)
B1—C1—C6—C5	178.75 (15)	B1'—C1'—C6'—C5'	−179.77 (15)
C12—N1—C8—C9	0.4 (2)	C12'—N1'—C8'—C9'	0.6 (2)
B1—N1—C8—C9	−178.28 (15)	B1'—N1'—C8'—C9'	−179.78 (14)
N1—C8—C9—C10	0.2 (2)	N1'—C8'—C9'—C10'	0.9 (2)
C14—N2—C10—C11	−1.7 (2)	C14'—N2'—C10'—C9'	174.39 (14)
C13—N2—C10—C11	−177.60 (15)	C13'—N2'—C10'—C9'	4.4 (2)
C14—N2—C10—C9	179.35 (16)	C14'—N2'—C10'—C11'	−6.6 (2)
C13—N2—C10—C9	3.4 (2)	C13'—N2'—C10'—C11'	−176.65 (14)
C8—C9—C10—N2	178.37 (14)	C8'—C9'—C10'—N2'	177.12 (14)
C8—C9—C10—C11	−0.7 (2)	C8'—C9'—C10'—C11'	−1.9 (2)
N2—C10—C11—C12	−178.48 (14)	N2'—C10'—C11'—C12'	−177.51 (14)
C9—C10—C11—C12	0.6 (2)	C9'—C10'—C11'—C12'	1.5 (2)
C8—N1—C12—C11	−0.5 (2)	C8'—N1'—C12'—C11'	−1.0 (2)
B1—N1—C12—C11	178.13 (15)	B1'—N1'—C12'—C11'	179.36 (14)
C10—C11—C12—N1	0.1 (2)	C10'—C11'—C12'—N1'	−0.1 (2)

Hydrogen-bond geometry (Å, º) top

Cg is the centroid of the C1'–C6' ring.

D—H···A	D—H	H···A	D···A	D—H···A
C9—H9A···Cg	0.95	3.12	4.069 (2)	178
C13—H13A···Cg	0.97	3.12	3.662 (2)	112
C13—H13C···Cg	0.97	3.23	3.662 (2)	109

Funding information

Funding for this research was provided by: Eastern Washington University Faculty Grants for Creative Works.

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