Reacción #357423

Ecuación de reacción

trimethyl-1,6-diisocyanatohexane

tetrahydrofuran

methanol

1,4-Butanediol vinyl ether

isocyanate

→

pale yellow oil

Rendimiento 89.0%

Bis[4-(vinyloxy)butyl] trimethyl-1,6-hexanediylbiscarbamate

Rendimiento 89.0%

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturareflux condenser
2. 2
   Temperaturato reflux
3. 3
   Otroabout 5 hours
4. 4
   Otroto quench any residual isocyanate
5. 5
   workup.STIRRINGthe solution was stirred for 0.5 hour
6. 6
   Otrothe residual oil was triturated with hexane (3×500 milliliters)
7. 7
   workup.DISSOLUTIONdissolved in methylene chloride (1 liter)
8. 8
   Lavadowashed with water (1×750 milliliters)
9. 9
   Secadodried over anhydrous magnesium sulfate
10. 10
    Filtraciónfiltered
11. 11
    Concentraciónconcentrated in vacuo

Procedimiento

To a 2 liter three neck flask equipped with a stopper, dropping funnel, stir bar, and reflux condenser was added trimethyl-1,6-diisocyanatohexane (mixture of 2,2,4- and 2,4,4-isomers, 118.7 grams, 0.57 mol, obtained from Sigma-Aldrich, Milwaukee, Wis.), dibutyltin dilaurate (3.56 grams, 5.6 mmol, obtained from Sigma-Aldrich) and anhydrous tetrahydrofuran (1 liter). 1,4-Butanediol vinyl ether (133.2 grams, 1.2 mol, obtained from Sigma-Aldrich) was added slowly dropwise to the stirring solution via the addition funnel. The reaction mixture was brought to reflux and was kept at this temperature until deemed complete by infrared spectroscopy (about 5 hours, confirmed by the disappearance of the isocyanate peak at 2200 cm−1). When the reaction was complete, methanol (500 milliliters) was added to quench any residual isocyanate and the solution was stirred for 0.5 hour. The solvent was stripped in vacuo and the residual oil was triturated with hexane (3×500 milliliters), dissolved in methylene chloride (1 liter), washed with water (1×750 milliliters), dried over anhydrous magnesium sulfate, filtered, and concentrated in vacuo to afford 221 grams of a pale yellow oil (89 percent yield). The product was believed to be a mixture of compounds of the formulae

Fuente