Water → tert-butyl N-ethenylcarbamate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A solution of N-formyl-N-vinyl-carbamic acid tert-butyl ester (103.6 g, crude 89% pure, 539 mmol) in THF (320 ml) was cooled to 0° C. and stirred rapidly. NaOH (2M, 323 ml, 6.46 mmol) was slowly added over ca 20 minutes. The internal temperature rose to 19° C., and began then to cool. After cooling to 5° C. the mixture was warmed to RT. After 1 hour the reaction was finished according to tlc and GC. The reaction mixture was shaken between tBuOMe (250 ml) and water (250 ml), washed with water (250 ml) and brine (250 ml), dried over MgSO4 and evaporated. The product was a yellow oil containing traces of THF (NMR). The crude product was dissolved in pentane (25 ml), seeded, and left overnight at −20° C. The colourless crystals were swirled in pentane, filtered off and washed 3× with pentane, then spread in the air to dry to yield 48.9 g (63%). The mother liquors were evaporated down, dissolved in a little pentane and seeded. A further 8.1 g (11%) was isolated. (The product can also be sublimed/distilled.) m.p. 67-68° C.

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