Novel Chiral Compound: (R) and (S) 1-(2-Benzyloxy-3-Methoxyphenyl)-2,2,2Trichloroethyl Benzensulfonate, Synthesys and characterization

Abstract

The reaction between benzimidazole 1 and benzenesulfonyl chloride 2 in dichloromethane (DCM) at 45 oC for 10 hr in the presence of dimethyl aminopyridine (DMAP) as a catalyst was expected to obtain 2(2-benzyloxy-3-methoxyphenyl)-1-(phenylsulfonyl)-1H-benzimidazole, 3. Unfortunately, a novel chiral compound (R) and (S) 1-(2-benzyloxy-3-methoxyphenyl)-2,2,2-trichloroethyl benzenesulfonate 4 was obtained as a single crystal (59% yield) with melting point of 58.4 °C. However, the mechanism of this reaction still is under investigation. The molecular structure of this compound was confirmed by FTIR, HRMS, X–Ray crystallography, 1D and 2D NMR spectroscopy. The crystal of 4 is in the monoclinic space group P21/c with a = 8.1638 (1) Å, b = 8.8536 (1) Å, c = 30.7221 (5) Å, β = 90.670 (1)o, Dcalc = 1.501 μg m-3, V = 2220.41 (5) Å and Rint = 0.059. The complete assignments of 4 were made using 1D and 2D NMR including APT, DEPT–135, COSY, HMQC and HMBC in CDCl3. 3 and R = 0.059. The complete assignments of 4 were made using 1D and 2D NMR

Keywords

• 1 H NMR, 13C NMR, 2D NMR, X–Ray Crystallography, 2,2,2-Trichloroethyl Benzenesulfonate

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