Preparation of trans cyclohexane 1,4-diisocyanate

US4439370A · kind A · utility

Assignee

• Akzona Incorporated · US

Inventors

• Hans Zengel · Kleinwallstadt, DE
• Manfred Bergfeld · Zell am Harmersbach, DE

Key dates

• Filing date: Sep 20, 1982
• Grant date: Mar 27, 1984
• Expiry date: Sep 20, 2002

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C07C311/56
• WIPO field: Organic fine chemistry
• WIPO sector: Chemistry

Abstract

A process is disclosed for selectively making trans-cyclohexane-1,4-diisocyanate, trans-cyclohexane-1,4-diamine, a trans-cyclohexane-1,4-diurethane, a trans-cyclohexane-1,4-diurea and trans-cyclohexane-1,4-disulphonyl urea by reacting ammonia with a mixture of cis and trans cyclohexane-1,4-dicarboxylic acid, a lower alkyl ester, a glycol ester, an oligomeric ester or a polyester to make a solid trans-dicarboxylic acid diamide in a first step. The diamide is chlorinated to form trans-cyclohexane-1,4-dicarboxylic acid-bis-N-chloramide. The latter compound is then converted into a (a) trans-cyclohexane-1,4-diamine with an alkali metal hydroxide or alkaline earth metal hydroxide; or into a (b) a trans-cyclohexane-1,4-diurethane by reaction with an alcohol or glycol in a reaction mixture containing an alkali metal hydroxide or alkaline earth metal hydroxide; or into (c) a trans-cyclohexane-1,4-diurea by reaction with a primary or secondary amine in a reaction mixture containing an alkali metal hydroxide or alkaline earth metal hydroxide; or into a (d) trans-cyclohexane-1,4-sulphonyl urea by reaction with a primary sulphonamide in a reaction mixture containing an alkali metal hydroxide a…