反应详情

0.89 g (127 mmol) of granulated lithium were added within 15 minutes to 200 ml (8 mol) of liquid ammonia at −37° C. The mixture was stirred until no more lithium floated (after approximately 15 minutes). A dark blue solution of lithium in liquid ammonia was obtained. 12.6 g (91 mmol) of myrcene were added portion wise within 30 minutes. The end of the formation of lithium amide could be recognized by the discoloration of the reaction mixture. 10.0 g (71 mmol) of 3-(1-methoxy-1-methyl-ethoxy)-propyne (90.8% GC) were added with a dropping funnel to the reaction mixture at −37° C. within 30 minutes. The reaction mixture was held at −37° C. for about 1 hour. 14.0 g (126 mmol) of bromoethane were added with a dropping funnel to the reaction mixture within 30 minutes. The reaction mixture was subsequently stirred for 1 hour. 157 ml of n-hexane were added to the reaction mixture and the liquid ammonia was evaporated under normal pressure within 15 hours. 50 ml of water were added to the reaction mixture at 22° C., and the mixture was stirred until all salt was dissolved. The organic layer was separated and concentrated under reduced pressure (40° C., 40 mbar). The crude product was analyzed by GC. 25.8 g of crude 1-(1-methoxy-1-methyl-ethoxy)-pent-2-yne were obtained (yield 83.0% based on 3-(1-methoxy-1-methyl-ethoxy)-propyne).

1. customthe liquid ammonia was evaporated under normal pressure within 15 hours
2. addition50 ml of water were added to the reaction mixture at 22° C.
3. stirringthe mixture was stirred until all salt
4. dissolutionwas dissolved
5. customThe organic layer was separated
6. concentrationconcentrated under reduced pressure (40° C., 40 mbar)