| 摘要 |
1316951 Alpha-isocyanatoalkyl arenes IMPERIAL CHEMICAL INDUSTRIES Ltd 9 June 1970 [24 June 1969 24 April 1970] 31891/69 and 19851/70 Heading C2C Alpha-isocyanatoalkyl arenes containing one or moreα-isocyanatoalkyl groups of the formula -CR 2 NCO (where each R is H or C 1-4 alkyl) are prepared by reacting an alpha-haloalkyl arene containing one or moreα-haloalkyl groups of the formula -CR 2 Hal (where Hal is halogen) with an alkali metal, alkaline earth metal, ammonium or methyl- or ethyl-substituted ammonium cyanate at elevated temperature in a solvent mixture comprising a solvent of high polarity (dielectric constant greater than 15), e.g. amides, ketones, sulphoxides, nitriles and carbonates and a halogenated aromatic hydrocarbon solvent of low polarity (dielectric constant less than 15). The temperature may be from 50‹ to 160‹ C. and a catalyst such as iodine or iodine monochloride may be present. An acid may be added to the reagents before isolation of the product. Alpha-isocyanatoalkyl mesitylenes containing up to three alpha-isocyanatoalkyl groups may be made by this process and are stated to be novel. Xylylene diisocyanates optionally alkyl, alkoxy or halogen substituted, benzyl isocyanate optionally alkyl, alkoxy or halogen substituted, and isocyanatoalkyl-naphthalenes, anthracenes, tetralins, diphenyls, diphenyl methanes and diphenyl ethers may be prepared by this process. |
