Crystal structure of bis(4-dìmethylaminopyridinium)methane dichloride bis(acetonitrile) solvate, C19H28Cl2N6

G.-V. Röschenthaler, R.-M. Schoth, E. Lork
1997 Zeitschrift für Kristallographie - New Crystal Structures  
C19H28CI2N6, orthorhombic, Pl\2\2\ (No. 19), a =10.544<2) Â, b =11.620(2) Â, c =18.298(4) Â, V =2241.9 À , Ζ =4, Ri F) =0.056, ft^f 2 ) =0.114. kCld) Source of material: 4-Dimethylaminopyridine (3.00 g, 24 mmol) was heated in methylene chloride at 323 Κ for 2 hours. After cooling to ambient temperature a colorless precipitate was obtained and extracted twice with S ml water. Ethanol (20 ml) was added to the water layer followed by an azeotropic distillation. The residue was treated with 5 ml
more » ... . ethanol. AU volatiles were removed in vacuo ( 10 mm). The yield was 2.77 g (70%, mp 543 K). The compound crystallizes with two acetonitril molecules per formula unit (not shown in the figure). All nitrogen atoms have almost trigonal planar geometry. The planes through NI, CI2, C13 and N4, C14, C15 show a 8.3° and 12.7° deviation, respectively to the corresponding ring attached. Both pyridinium moieties exhibit a substantial quinoidal character (see réf. 1) as seen from the C2-C3 (133.6 pm) and C4-C5 (135.6 pm) distances being significantly shorter than C1-C2 (143.8 pm) and C1-C5 (141.4 pm). The bond length Cl-N(l) (132.9 pm) is found to be between a single and double bond (147 pm and 127 pm, respectively) (see ref. 2).
doi:10.1524/ncrs.1997.212.1.397 fatcat:rrz5dzowvbfe5avlcd43ktzaoi