Methyl 2-(N-ethylmethanesulfonamido)benzoate

In the molecule of the title compound, C11H15NO4S, the S atom environment is distorted tetrahedral. The methoxycarbonyl group is oriented at a dihedral angle of 11.8 (2)° with respect to the benzene ring. In the crystal structure, intermolecular C—H⋯O hydrogen bonds link the molecules into centrosymmetric dimers.

In the molecule of the title compound, C 11 H 15 NO 4 S, the S atom environment is distorted tetrahedral. The methoxycarbonyl group is oriented at a dihedral angle of 11.8 (2) with respect to the benzene ring. In the crystal structure, intermolecular C-HÁ Á ÁO hydrogen bonds link the molecules into centrosymmetric dimers.

Comment
Alkyl anthranilates are valuable starting materials for the preparation of pesticides, dyes and drugs (Reissenweber & Mangold, 1982). They find organoleptic uses in augmenting the aroma or taste of perfume compositions, colognes, perfumed articles, foodstuffs, medicinal products and in enhancing the effects of deodorancy (Mookherjee et al., 1989). Particularly, the N-substituted thioesters of anthranilic acid have been found potent inhibitors of the serine proteases human leukocyte (HL) elastase, porcine pancreatic elastase, cathepsin G, and bovine chymotrypsin A α (Tadashi et al., 1982). In continuation of our research program to synthesize new biologically important 1,2-benzothiazine 1,1-dioxide molecules (Siddiqui et al., 2006;Siddiqui et al., 2007a,b), we embarked on the syntheses of 2,1-benzothiazine 2,2-dioxide, as well. Contrary to the N-methyl substituent (Lombardino, 1972), the N-ethyl derivative is being reported for the first time.
The title compound, (I), is an important precursor for the synthesis of 2,1-benzothiazine 2,2-dioxide molecule. The structure determination of (I) is undertaken in order to understand the conformational geometry around the sulfur and nitrogen atoms, due to the addition of ethyl group.
In the molecule of (I), (Fig. 1) S1 atom adopts a distorted tetrahedral coordination geometry with two O, one N and one C atoms of methylsulfonyl amino group (Table 1) In the crystal structure, intermolecular C-H···O hydrogen bonds (Table 2) link the molecules into centrosymmetric dimers (Fig. 2), in which they may be effective in the stabilization of the structure.

Experimental
For the preparation of the title compound, the suspension of hexane-washed sodium hydride (50% in mineral oil) was prepared in dry dimethylformamide (3 ml). A solution of methyl N-methylsulfonylanthranilate (70 mg, 0.306 mmol) in dry dimethylformamide (5 ml) was added to the suspension (76 mg, 0.368 mmol), and stirred for 45 min at room temperature.
Then, a solution of ethyl iodide (144 mg, 0.92 mmol) in ether (5 ml) was added to it. The resulting white suspension was stirred for 1.5 h and poured into hydrochloric acid (3 N, 50 ml) to produce a yellow suspension which was extracted with chloroform (4 × 25 ml). The combined extract was dried over calcium sulfate and evaporated under reduced pressure (11 torr) to get the title compound (yield; 58 mg, 73%, m.p. 330-331 K). Crystals suitable for X-ray analysis were obtained by slow evaporation of CHCl 3 . supplementary materials sup-2 Refinement H atoms were positioned geometrically, with C-H = 0.93, 0.97 and 0.96 Å for aromatic, methylene and methyl H, and constrained to ride on their parent atoms, with U iso (H) = xU eq (C), where x = 1.5 for methyl H, and x = 1.2 for all other H atoms. Fig. 1. The molecular structure of the title molecule, with the atom-numbering scheme. Displacement ellipsoids are drawn at the 30% probability level.  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 > 2sigma(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.