Zwitterionic bis(phenolate)amine lanthanide complexes for the ring-opening polymerisation of cyclic esters.
نویسندگان
چکیده
The reaction of Sm{N(SiMe3)2}3 with the bis(phenol)amines H2O2N(R) (H2O2N(R) = RCH2CH2N(2-HO-3,5-C6H2(t)Bu2)2; R = OMe, NMe2 or Me) gave exclusively zwitterions Sm(O2N(R))(HO2N(R)). For R = OMe or NMe2 these were efficient catalysts for the ring-opening polymerisation of epsilon-caprolactone and D,L-lactide with a tendency to form cyclic esters; in contrast, no polymerisation was observed for R = Me.
منابع مشابه
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ورودعنوان ژورنال:
- Dalton transactions
دوره 1 شماره
صفحات -
تاریخ انتشار 2008