2,5-dimethyloxolane

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: Prior to optimization of the initial H2/H2S atmosphere and the mol % catalyst of presulfided Pt (Pt—S/C) employed, a range of solvents is examined (Table 5). No formation of caprolactam is observed using acetonitrile (entry 1, Table 5) as solvent. The highest yield of caprolactam is achieved using THF (entry 2, Table 5). Use of 2,5-dimethyltetrahydrofuran (entry 3, Table 5) results in a tenfold reduction in the yield of caprolactam relative to use of THF as solvent (entry 3 vs. entry 2, Table 5).

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: A mixture of 55.5 g (0.5 mole) 2-aminothiazole (90% pure) and 66 g (0.5 mole) 2,5-dimethyltetrahydrofuran is placed in a 1-liter 3-neck flask equipped with a stirrer, addition funnel, thermometer, and condenser, and 200 ml glacial acetic acid is added dropwise with stirring while maintaining the temperature below 20°C. After stirring for an additional 15 minutes, the reaction mixture is refluxed for 30 minutes and then cooled, made basic (pH 9-10) with 375 ml 30% sodium hydroxide, and steam-distilled to yield 1500 ml distillate. is placed in a 1-liter 3-neck flask equipped with a stirrer, addition funnel while maintaining the temperature below 20°C After stirring for an additional 15 minutes the reaction mixture is refluxed for 30 minutes cooled steam-distilled to yield 1500 ml distillate