N-p-Tolyladamantane-1-carboxamide

In the crystal of the title compound, C18H23NO, the molecules are linked into chains along the c axis by intermolecular N—H⋯O hydrogen bonds.

In the crystal of the title compound, C 18 H 23 NO, the molecules are linked into chains along the c axis by intermolecular N-HÁ Á ÁO hydrogen bonds.

N-p-Tolyladamantane-1-carboxamide
Weiwei SiMa S1. Comment The unique structure of adamantane and the pharmaccutical effects of adamantane-containing agents on virus (Davis et al., 1964) have attracted many chemists and pharmacologists to do considerable work on the syntheses of adamantane derivatives (Fort et al., 1964). The crystal structure of the title compound (I) is reported herein.
The molecular structure of compound (I), C 18 H 23 ON, is shown in Figure 1. All bond lengths and bond correspond to the geometry parameters expected for atom types and the type of hybridization (Allen et al., 1987). The bonds to nitrogen of the title amide, Fig. 1, the torsion angles of O1-C8-N1-C1 and C9-C8-N1-C1 are 1.70 (3)° and 178.59 (18)°, respectively. The C8-N1 bond has considerable double-bond characer, at 1.349 (2) Å, is substantially shorter than the normal C-N single-bond distance observed in amines. In the crystal of (I), the intermolecular N 1 -H···O 1 H-bonds linked molecules to chains along the c axis (Fig.2). And the N 1 -H···O 1 bond length is 2.962 (2) Å.

S2. Experimental
A solution of freshly prepared 1-adamantane carbonyl chloride (1 mmol, prepared by refluxing 1-adamantane carboxylic acid with 3M excess of SOCl 2 ) in dry CH 2 Cl 2 was added dropwise to a well stirred and ice-cooled solution of p-toluidine (1 mmol) and triethylamine (2 mmol) in the same solvent. After 24 h of stirring at room temperature, the solvents were removed in vacuo and the residue was recrystallized from methanol. Colorless single crystals of the title compound suitable for X-ray diffraction analysis were obtained then and the yield was 80% (Isabella et al. 1997;Tadashi et al., 1969).

S3. Refinement
Positional parameters of all the H atoms were calculated geometrically and were allowed to ride on the C atoms to which they are bonded, with U iso (H) = 1.2U eq (C).  The molecular structure of the title compound, with the atomic numbering scheme. Displacement ellipsoids are drawn at the 30% probability level, and all H atoms have been omitted for clarity.    Refinement. Refinement of F 2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F 2 , conventional R-factors R are based on F, with F set to zero for negative F 2 . The threshold expression of F 2 > σ(F 2 ) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F 2 are statistically about twice as large as those based on F, and R-factors based on ALL data will be even larger.