Reaktion #1120440

Reaktionsgleichung

α,α-dimethyl-m-isopropenylbenzyl isocyanate

t-butyl alcohol

→

{1-methyl-1-[3-(1-methylethenyl)phenyl]ethyl}carbamic acid 1,1-dimethylethyl ester

Ausbeute 81.0%

Lösungsmittel

hexane

Reaktionsbedingungen

Aufarbeitung

1. 1
   SonstigeInto a 3-neck, 10 L round bottom flask equipped with a mechanical stirrer, condenser, and a nitrogen inlet
2. 2
   workup.ADDITIONThroughout the addition the reaction temperature
3. 3
   Temperaturincreased to 50° C
4. 4
   workup.WAITThe reaction was complete within an hour
5. 5
   WaschenThe reaction mixture was washed with water (5 L)
6. 6
   Sonstigethe organics were separated from the aqueous layer
7. 7
   TrocknenThe organics were dried over magnesium sulfate
8. 8
   Filtrationfiltered
9. 9
   Sonstigeevaporated
10. 10
    Sonstigeto yield a yellow-brown semi-solid
11. 11
    SonstigeRecrystallization from hexane

Vorschrift

Into a 3-neck, 10 L round bottom flask equipped with a mechanical stirrer, condenser, and a nitrogen inlet was placed α,α-dimethyl-m-isopropenylbenzyl isocyanate (1083 g, 5.38 mol), hexane (6 L), and t-butyl alcohol (398.8 g, 5.38 mol). While the mixture was stirred at room temperature, potassium t-butoxide (18.0 g, 160 mmol) was added in portions. Throughout the addition the reaction temperature increased to 50° C. The reaction was complete within an hour. The reaction mixture was washed with water (5 L), and thereafter, the organics were separated from the aqueous layer. The organics were dried over magnesium sulfate, filtered, and evaporated to yield a yellow-brown semi-solid. Recrystallization from hexane afforded essentially pure {1-methyl-1-[3-(1-methylethenyl)phenyl]ethyl}carbamic acid 1,1-dimethylethyl ester (1193 g, 81% isolated yield), as shown by proton and carbon-13 NMR spectroscopy.

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