Phosgene → 2,4,6-Trichlorophenyl Isocyanate

1,1,3,3-tetramethylurea (1.52 ml, 12.75 mmoles) was added to a solution of phosgene (50.0 g, 505.43 mmoles) dissolved in toluene (150 ml). The resulting solution was stirred for 10 min. at which time 2,4,6-trichloroaniline (10.0 g, 50.90 mmoles) was added. The solution was heated to a temperature of 70°-80° C. for 1.5 hr. and then refluxed for 1.5 hr. while phosgene was bubbled in. After removing excess phosgene under reduced pressure, the clear upper layer solution was collected by decantation from the bottom oil layer, and the bottom oil layer was discarded. The solution was then evaporated to give a solid. The solid was dried under a vacuum to give a white solid (11.3 g, 99.3 pct). This product was recrystallized from dry carbon tetrachloride to give a colorless crystalline compound, m.p. 65°-66° C.; Infrared (IR): γ max 2,282 cm-1 (NCO); nuclear magnetic resonance (NMR) (chloroform-d): τ, 2.7 (2-proton singlet, H-3,5, aromatic protons).

1. additionwas added
2. temperatureThe solution was heated to a temperature of 70°-80° C. for 1.5 hr
3. temperatureand then refluxed for 1.5 hr
4. customwhile phosgene was bubbled in
5. customAfter removing excess phosgene under reduced pressure
6. customthe clear upper layer solution was collected by decantation from the bottom oil layer
7. customThe solution was then evaporated
8. customto give a solid
9. customThe solid was dried under a vacuum
10. customto give a white solid (11.3 g, 99.3 pct)
11. customThis product was recrystallized from dry carbon tetrachloride
12. customto give a colorless crystalline compound, m.p. 65°-66° C.

ORD record

ord-ce0c911f499c4ad3a9da127f8c7a7047

Source dataset

uspto-grants-1984_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04477389