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US 4,379,767 AGranted
Manufacture of isocyanates
AssigneeAmerican Cyanamid Company
InventorsVazken A. Alexanian, Peter S. Forgione, Laurence W. Chang
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Abstract
A process for the production of tertiary benzyl isocyanates by reaction of the corresponding olefin with a carbamoyl halide to form the benzyl halide followed by the reaction of the benzyl halide with an excess of isocyanic acid to form the isocyanate and carbamoyl halide which can be recovered and recycled.
Claims11
A process for the production of tertiary benzyl isocyanates which comprises reacting a vinyl aromatic compound of the formula:
- ##STR3## in which:
- R.sub.1 is an alkylidene group having from 1 to 3 carbon atoms,
- R.sub.2 is an alkyl group having from 1 to 3 carbon atoms, and
- R.sub.3 is a phenyl, biphenyl or naphthyl group or a substituted phenyl, biphenyl or naphthyl group having substituents selected from halogen atoms, methyl and methoxy groups and substituents of the formula:
- ##STR4## with a carbamoyl halide in a solvent for said aromatic compound, carbamoyl halide, isocyanic acid and reaction products thereof to produce the corresponding aromatic halide and reacting said aromatic halide in said solution with isocyanic acid in sufficient excess to form the corresponding aromatic isocyanate and carbamoyl halide.
2 more elements
Dependencies are inferred from the claim text.