Benzenesulfonyl chloride

The precursor’s benzenesulfonyl chloride and morpholine were purchased commercially from Sigma–Aldrich (St. Louis, USA). The precursors were used without further purification. The title compound 4-(Phenylsulfonyl) morpholine was prepared by reaction of 1 equivalent of benzenesulfonyl chloride (1 mmol) and morpholine (2 mmol) in methanolic mixture of pyridine (5 mL) at low temperature (∼0 °C) under stirring by 2 h as a previously described procedure (Buchmann and Schalinatus, 1962 ). The material thus formed was filtered and washed with methanol solution then dried. The resulting material was recrystallized by using heating methanol solution. The crystals were formed by slow solvent evaporation at room temperature. The complete structure elucidation was confirmed by NMR ¹H and ¹³C spectroscopy analysis by comparison with literature data (Modarresi-Alam et al., 2009 (link)). The NMR spectra in CDCl₃, were recorded in Varian-Mercury 300 (300 MHz for ¹H and 75 MHz for ¹³C) spectrometer, using tetramethylsilane (TMS) as internal standard. Analytical Data: ¹H RMN (CDCl₃, 300 MHz): t (4H; 3.01 ppm); t (4H; 3.74 ppm); t (2H, J = 7.56 Hz); t (1H; 7.64 ppm); d (2H; 7.77 ppm) ¹³C RMN (CDCl₃, 75 MHz): δ = 46; 66.10; 127.85; 129.15; 133.09; 135.13. The synthesis is described by the scheme present in Fig. 1.

All chemicals are used without prior purification (Merck, USA). Benzenesulfonyl chloride and 4-nitrophenol (Sigma-Aldrich, USA) were used as starter material. Reduction and diazotization reaction methods were used to synthesize the compound in the title. Na₂SO₃ (Sigma-Aldrich, USA) was used as a reductor in HCl concentrate solvent, and NaNO₂ in HCl was used in diazotization reaction.