A Concise, Novel Route to 1,3-Benzoxathian Derivatives

Abstract

Novel 1,3-benzoxathian derivatives were successfully prepared in a one-pot process via a tandem ring-closure/β-elimination pathway from easily accessible o-thio-substituted phenols.

Key words

1,3-Benzoxathian - annulation - phenols - ring-closure - elimination

References

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10

PP powder (1.3 kg) was blended with Irganox 1010 (0.05%), calcium stearate (0.05%), Irgafos 168 (0.02%) and the 1,3-benzoxathian derivative (0.02%). The blend was extruded in an extruder having a cylinder diameter of 20 mm and a length of 400 mm at 100 rpm. The three heating zones being adjusted to the following temperatures: 260, 270 and 280 ˚C. The extrudate was cooled down, granulated and extruded again. After three extrusions, the MFI was measured at 230 ˚C/2.16 kg.