Received 22 December 2004
The title compound, C12H12N3·BH3 or C12H15BN3, contains a BH3 group and two picolyl groups attached to a central N atom. Both edge-to-face and face-to-face -stacking interactions are found.
The asymmetric unit of the title compound, (I), contains one molecule. The two planar pyridyl rings are twisted (Fig. 1) about the central N atom, with an interplanar angle of 110.9°. The amine N atom is not involved in any hydrogen bonding but pyridyl atom N1 interacts with atom C3 in an adjacent ring (Table 1).
An edge-to-face interaction is found between the H atom on C2 and the plane of the pyridine ring containing atom N3 (Fig. 2). This H atom is 2.806 Å from the mean plane of the pyridine ring at (½ + x, ½ - y, ½ + z). The pyridine ring containing atom N3 is -stacked with its symmetry equivalent by inversion (symmetry code: 2 - x, -y, 1 - z). The interplanar and the centroid-to-centroid distances are 3.496 (2) and 3.971 Å respectively (Fig. 2).
| || Figure 1 |
Perspective view of (I), showing 50% probability displacement ellipsoids.
| || Figure 2 |
View showing the C-HN bond (C3 and N1), the interaction between the H atom bonded to C2 and the pyridyl ring, and the -stacking of the N3-containing pyridine rings [symmetry codes: (i) ½ + x, ½ - y, z - ½; (ii) 2 - x, -y, 1 - z; (iii) ½ + x, ½ - y, ½ + z.]
2-(Aminomethyl)pyridine (4.95 g, 44.77 mmol) and pyridine-2-carboxaldehyde (4.96 g, 46.31 mmol) were dissolved in methanol (150 ml) (Lambert et al., 1997). The solution was stirred for 2 h at room temperature (yellow-orange solution). After slow addition of an excess of sodium borohydride, stirring was continued for 1 h (pale-yellow solution). The solvent was removed by rotary evaporation to give bis(pyridin-2-ylmethyl)amine (6.43 g, 73%) as an orange oil. Colourless crystals of the borane adduct appeared as a minor product after the oil was stored in a freezer overnight.
H atoms bonded to C and B atoms were placed at calculated positions; the constrained C-H distances were 0.95, 0.98 and 0.99 Å for H atoms bonded to Csp2, Bsp3 and methylene C atoms, respectively. They were refined using a riding model, with Uiso(H) = 1.2Ueq(B,C). The H atom bonded to the amine N atom was located in a difference map and the coordinates freely refined with a fixed Uiso value of 0.03 Å.
Data collection: SMART (Bruker, 1998); cell refinement: SAINT (Bruker, 1998); data reduction: SAINT; program(s) used to solve structure: SHELXS97 (Sheldrick, 1997); program(s) used to refine structure: SHELXL97 (Sheldrick, 1997); molecular graphics: SHELXTL (Bruker, 2001); software used to prepare material for publication: SHELXTL.
We are grateful to the Socrates Exchange Programme for support. JW thanks the Erskine fund at the University of Canterbury for support.
Bruker (1998). SMART, SAINT and SADABS. Bruker AXS Inc., Madison, Wisconsin, USA.
Bruker (2001). SHELXTL. Version 6.12. Bruker AXS Inc., Madison, Wisconsin, USA.
Lambert, E., Chabut, B., Chardon-Noblat, S., Deronzier, A., Chottard, G., Bousseksou, A., Tuchages, J.-P., Laugier, J., Bardet, M. & Latour, J.-M. (1997). J. Am. Chem. Soc. 119, 9424-9437.
Sheldrick, G. M. (1997). SHELXS97 and SHELXL97. University of Göttingen, Germany.