Yield:59801-62-6 100%

Reaction Conditions:

with hydrogenchloride in tetrahydrofuran;methanol;water at 20; for 5 h;

Steps:

54-3 Production example 54-3; Thiomorpholine 1,1-dioxide monohydrochloride

tert-Butyl 1,1-dioxothiomorpholine-4-carboxylate (2.03 g, 8.63 mmol) was dissolved in a mixture of hydrochloric acid-methanol 10 (20 ml, purchased from Tokyo Kasei Kogyo Co., Ltd) and tetrahydrofuran (20 ml); hydrochloric acid (4.0 ml) was added thereto during stirring at room temperature; and the reaction mixture was stirred at room temperature for 3 hours. The reaction mixture was concentrated; methanol (20 ml), tetrahydrofuran (20 ml) and hydrochloric acid (4.0 ml) were added to the obtained crystals. Furthermore, water (10 ml) was added to this solution to perfectly dissolve the crystals; and this solution was stirred at room temperature for 1 hour. The solvent was concentrated under reduced pressure; and the obtained crystals were suspended in methanol, filtered off, washed with methanol, and dried under aeration to yield the title compound as colorless crystals (1.49 g, 8.65 mmol, quantitative). ¹H-NMR Spectrum (DMSO-d₆) δ (ppm): 3.54 (8H, m), 9.83 (2H, brs).

References:

EP1522540,2005,A1 Location in patent:Page/Page column 70