Crystal structure of N-(propan-2-ylcarbamothioyl)benzamide

In the crystal structure of the title compound, C11H14N2OS, the six atoms of the central C2N2OS residue are coplanar (r.m.s. deviation = 0.002 Å), which facilitates the formation of an intramolecular N—H⋯O hydrogen bond, which closes an S(6) loop. The terminal phenyl ring is inclined with respect to the central plane [dihedral angle = 42.10 (6)°]. The most prominent feature of the crystal packing is the formation of {⋯HNCS}2 synthons resulting in centrosymmetric dimers.

Symmetrical and unsymmetrical thioureas have shown anti-fungal activity against the plant pathogens like Penicillium expansum and Fusarium oxysporum (Rodriguez-Fernandez et al., 2005). Also, 1,3-dialkyl or diaryl thioureas exhibited significant anti-fungal activity against Pyricularia oryzae and Drechslera oryzae (Rauf et al., 2012). In light of this, and following to our on-going study in synthesis of bio-active molecules, we report here the synthesis and crystal structure of the title compound.
In the structure of the title compound, Fig. 1, intramolecular N-H···O and intermolecular N-H···S interactions are noted (Table 1).

S2. Synthesis and crystallization
Freshly prepared benzoyl chloride 5 ml (0.043 mol) was added drop wise to a solution of 3.2 g (0.042 mol) of ammonium thiocyanate in 20 ml dry acetone with stirring. The reaction mixture was refluxed for 3 h. The obtained solid precipitate ammonium chloride was filtered off. The formed benzoyl isothiocyanate in the filtrate was added to a solution of 3.1 ml (0.0425 mol) of 2-amino-isopropane in 20 ml dry acetone. The reaction mixture was heated under reflux for 5 h, then poured into a beaker containing some ice cubes. The resulting precipitate was collected by filtration, washed several times with cold ethanol/water and purified by recrystallization from ethanol/dichloromethane mixture (1:1). Yield (63%); colourless solid, m.p 418 K.

S3. Refinement
Carbon-bound H-atoms were placed in calculated positions (C-H = 0.93 to 0.98 Å) and were included in the refinement in the riding model approximation, with U iso (H) = 1.2-1.5U eq (C). The hydrogen atoms attached to N1 and N2 were found from difference Fourier maps and were refined with the distance contratin N-H = 0.86±0.02 Å with unrestrained U iso .

Figure 1
Perspective view of the title molecule with atom labeling scheme and 50% probability ellipsoids.

Figure 2
Packing viewed down the b axis showing stacks of pairs of molecules connected by N-H···S interactions. where P = (F o 2 + 2F c 2 )/3 (Δ/σ) max < 0.001 Δρ max = 0.37 e Å −3 Δρ min = −0.34 e Å −3 Special details Geometry. Bond distances, angles etc. have been calculated using the rounded fractional coordinates. All su's are estimated from the variances of the (full) variance-covariance matrix. The cell e.s.d.'s are taken into account in the estimation of distances, angles and torsion angles Refinement. Refinement on F 2 for ALL reflections except those flagged by the user for potential systematic errors. Weighted R-factors wR and all goodnesses 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 observed criterion of F 2 > σ(F 2 ) is used only for calculating -R-factor-obs 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.