Propylene diamine dimerisation, trimerisation - by heating with Gp. VIII metal catalyst, pref. with hydrogen

摘要

Prepn. of dipropylene triamine and tripropylene tetramine comprises condensing 1,2- or pref. 1,3-propylene diamine at 50-250 degrees C, pref. in presence of H2 and opt. with addn. of NH3. A Gp. VIII metal-contg. catalyst is used, including noble metals, and NH3 is produced during reaction. Higher polycondensates are decomposed to the dimers and trimers. At 25-200 bars H2 pressure and 160-200 degrees C conversions of ca 60% and sometimes ca 100% are obtd. for reaction times of 1-4 hrs. Good specificity for the dimer can be obtd. Prods. can be sepd. easily by distillation; very little prodn. of cyclic, branched or partially deaminated prods. occurs.