Methane → HCID 22447446, compound

38.8 mL diphosgene is added dropwise over 1 hour to a mixture of 35 g glycine methyl ester hydrochloride and 0.4 g activated charcoal in 400 mL dioxane under N2. The reaction mixture warms to 80° C. during this time. The reaction mixture is then heated and stirred at reflux for 21/2 hours. The reaction mixture is then cooled, filtered, and concentrated to dryness by rotary evaporator, keeping exposure to moistureto a minimum. The crude product is re-dissolved in 100 mL THF, and the pH of the solution is adjusted to 5.5-6.0 by addition of pyridine. The product mixture is again filtered, and the product is purified by fractional distillation to give pure glycine methyl ester isocyanate in ~70% yield (bp 60° C., 13 mm Hg).

1. customwarms to 80° C. during this time
2. temperatureThe reaction mixture is then heated
3. temperatureat reflux for 21/2 hours
4. temperatureThe reaction mixture is then cooled
5. filtrationfiltered
6. concentrationconcentrated to dryness by rotary evaporator
7. dissolutionThe crude product is re-dissolved in 100 mL THF
8. additionthe pH of the solution is adjusted to 5.5-6.0 by addition of pyridine
9. filtrationThe product mixture is again filtered
10. distillationthe product is purified by fractional distillation

ORD record

ord-74f32f2a22c442439dbb71c8340313cf

Source dataset

uspto-grants-1989_09

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04868061