Secondary Distillation or Vacuum Distillation

Methylmorpholine-4-oxide monohydrate [7529-22-8] M 135.2, m 71-73 . When dried for 2-3h at high vacuum it dehydrates. Add MeOH to the oxide and distil off the solvent under vacuum until the temp is ca 95°. Then add Me2CO at reflux then cool to 20°. The crystals are filtered off washed with Me2CO and dry. The degree of hydration may vary and may be important for the desired reactions, [van Rheenan et al. Tetrahedron Lett 1973 1076 Schneider and Hanze US Pat 2 769 823 see also Sharpless et al. Tetrahedron Lett 2503 / 976.1  [c.295]

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Crude oil Petroleum products Process flowsheets  -> Secondary Distillation or Vacuum Distillation