2,2-Dichloro-1-(2-phenyl-1,3-oxazolidin-3-yl)ethanone

In the title molecule, C11H11Cl2NO2, the oxazolidine ring is in an envelope conformation with the O atom forming the flap; the other four essentially planar ring atoms (r.m.s. deviation = 0.012 Å) form a dihedral angle of 91.1 (3)° with the phenyl ring. In the crystal structure, molecules are linked by weak intermolecular C—H⋯O hydrogen bonds, forming one-dimensional chains.

In the title molecule, C 11 H 11 Cl 2 NO 2 , the oxazolidine ring is in an envelope conformation with the O atom forming the flap; the other four essentially planar ring atoms (r.m.s. deviation = 0.012 Å ) form a dihedral angle of 91.1 (3) with the phenyl ring. In the crystal structure, molecules are linked by weak intermolecular C-HÁ Á ÁO hydrogen bonds, forming onedimensional chains.

Comment
Substituted oxazolidines are important synthetic targets due to their biological activity (Agami et al., 2004), pharmacological activity and their extensive use as chiral auxiliaries for the synthesis of many chiral compounds (Guirado et al., 2003;Tararov et al. 2003). Dichloroacetemide compounds have been shown to act as herbicide safeners (Hatzios, 2004;Daniele et al., 2007). As part of our ongoing investigations of oxazolidine derivatives we prepared the title compound and its crystal structure is reported herein.
The molecular structure of the title compound is shown in Fig.1. In the crystal structure, molecules are linked by weak intermolecular C-H···O hydrogen bonds to form one-dimensional chains (Fig. 2).

Experimental
The title compound was prepared by a slightly modified literature procedure (Fu et al., 2009). Ethanolamine (4.1 g, 0.067 mol) and 7.1g (0.067mol) of benzaldehyde were mixed with 25mL of benzene. The reaction mixture was stirred for 1h at 306-308K. Then, the mixture was heated to reflux and water was evaporated, followed by cooling to 273K and 7.5 mL of 33% sodium hydroxide solution was added. 11.8 g (0.08mol) of dichloroacetyl chloride was added dropwise with stirring, keeping the temperature at 273-277K. Stirring was continued for 1.5h. The mixture was rinsed with water until the pH=7. The organic phase was dried over anhydrous magnesium sulfate and the benzene was removed under vacuum. The crude product was recrystallized with ethyl acetate and light petroleum, white crystals wre obtained.
The single-crystal suitable for X-ray structural analysis was obtained by slow evaporation of a solution of the title compound in petroleum ether and ethyl acetate at room temperature.