| 摘要 |
A method for the production of hexamethylenediamine from butadiene involves catalytic mono-epoxidation, base-catalysed addition of hydrogen cyanide, acid-catalysed dehydration of the mixed cyanhydrins to cis/trans-pentadieno-nitrile, base-catalysed addition of HCN to give cis/trans-1,4-dicyano-butene isomers, and catalytic hydrogenation of these dinitriles. A method for the production of hexamethylenediamine (I) from butadiene involves: (i) catalytic epoxidation to 1,2-epoxy-3-butene (II); (ii) base-catalysed addition of hydrogen cyanide to (II) to give a mixture (III) of 3-hydroxy-4-penteno-nitrile and 2-hydroxymethyl-3-butenonitrile; (iii) acid-catalysed dehydration of these cyanhydrins (III) to cis/trans-pentadienonitrile (IV); (iv) base-catalysed addition of HCN to (IV) to give cis/trans-1,4-dicyanobutene-1 and -2 (V); and (v) catalytic hydrogenation of (V) to give (I). Independent claims are also included for (1) a method for the production of cis-trans-1,4-dicyanobutenes, especially 1,4-dicyanobutene-2, by the addition of HCN to cis/trans-pentadieno-nitrile in presence of an alkali pyrophosphate or dialkali hydrogen phosphate catalyst (2) a method for the production of (I) from 1,2-epoxy-3-butene (II) by addition of HCN in presence of a catalyst selected from alkali hydroxides, alkaline earth hydroxides (other than aqueous calcium hydroxide), alkali or alkaline earth cyanides, basic ion exchange resins (OH form) and aliphatic or carbocyclic sec. or tert. amines, to give a mixture containing cyanhydrins (III), followed by stages (iii), (iv) and (v) as above.
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