| 摘要 |
1,225,450. Aliphatic diisocyanates. FARBENFABRIKEN BAYER A.G. 18 Dec., 1969 [7 Jan., 1969], No. 61662/69. Heading C2C. Aliphatic diisocyanates are prepared by reacting phosgene with salts of aliphatic aminohydroxamic acids with volatile acids, e.g. hydrochloric, hydrobromic, carbonic and sulphurous acids. Preferred aminohydroxamic acids are those of the formula where n is an integer from 4 to 17, e.g. 6-aminocaproichydroxamic acid as its hydrochloride. The aminohydroxamic acids may be prepared in situ by the ring opening of a cyclic lactam by the salt of hydroxylamine and a volatile acid. |
