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Synthesis and Post-Polymerization Functionalization of Halogen-Substituted Polyphosphinoboranes to Access
Marius I Arz1, Alastair W Knights1, Ian Manners1,2
1School of Chemistry, University of Bristol, Cantock's Close, Bristol, BS8 1TS, UK.
Abstract:
Catalytic dehydropolymerization of halogen-functionalized phosphine-boranes (4-X-C6 H4 )PH2 ⋅BH3 (1a: X = Br, 1b: X = I) with [CpFe(CO)2 (OTf)] at 100 °C provides convenient access to halogen-functionalized polyphosphinoboranes [(4-X-C6 H4 )PH-BH2 ]n (2a: X = Br, 2b: X = I). These polymers are useful precursors for post-polymerization functionalization, which is demonstrated by Sonogashira coupling under mild conditions to yield the alkynyl-functionalized polyphosphinoborane [(4-PhCC-C6 H4 )PH-BH2 ]n (3).
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