Structures of polyfluoroaromatic compounds. IV. Crystal structure of 2-nitrononafluorobiphenyl

Abstract

Crystals of C12FgNO2 are monoclinic, space group P21/c, with a = 11.30 (1), b = 7.79 (1), c = 15.22 (1) A, fl --114.75 (5) °, Z = 4. The structure was refined to R = 4.7% for 1407 observed counter amplitudes. The angle between the phenyl-ring planes is 85.5 ° and the nitro group is inclined at 56 ° to its phenyl ring. The inter-ring bond length is 1.492 A (uncorrected for thermal libration). Estimated standard deviations are 0.004-0.005 A for bond lengths and 0.3-0.4 ° for bond angles.

Reverse Sandwich Structures from Interplay between Lone Pair−π-Hole Atom-Directed C···dz2[M] and Halogen Bond Interactions

“…It is noteworthy that relevant C–I···NC linkages were previously identified − upon studies of linear supramolecular chains and some other more complex structures held by XB. Similar C···O lp­(O)···πh short contacts were observed in the structures of picryl iodide and 2-nitroperfluorobiphenyl . The related πh ability of sym -trichlorotrinitrobenzene toward self-association and toward diacetone diperoxide was also documented.…”

“…Similar C•••O lp(O)•••πh short contacts were observed in the structures of picryl iodide 65 and 2-nitroperfluorobiphenyl. 66 The related πh ability of sym-trichlorotrinitrobenzene toward self-association 67 and toward diacetone diperoxide 68 was also documented. In turn, lp(N)•••πh interactions involving cyano groups were identified in a substantial number of phthalonitriles, including hexa- 69 and tetracyanobenzenes, 70 and also tetrafluorophthalonitriles.…”

Structure of 2H,2'H-octafluorobiphenyl

“…Replacement of F by H in the 2-position in perfluorobiphenyl has virtually no effect on the dihedral angle, whereas replacement in the 2-and 2'-positions reduces the angle by about 5 °. 2-substitution with NO 2 and 2,2'-disubstitution with Br produce a marked increase in the dihedral angle (Hamor & Hamor, 1978b. In contrast, the inter-ring bond length is little affected by the nature of the ortho substituent and lies within the narrow range 1.486 (5) to 1.492 (4) A.…”

Structure of 1-bromo-3,4,5-trifluoro-2,6-bis(pentafluorophenyl)benzene

“…The inter-ring bond length and dihedral angle are both less (by 0.02 A and 7 ° respectively) than in 2-nitrononafluorobiphenyl (Hamor & Hamor, 1978).…”