Studies Toward the Living Polymerization of Phenylethynyl-Calix[4]arene Compounds with Rh-based Ternary Catalytic Systems

José V. Prata (1)

1 Chemical Engineering Department and Centro de Investigação de Engenharia Química e Biotecnologia

The living polymerization of mono and difunctional-phenylethynylcalix[4]arene compounds 1 and 2 by Rh(I) ternary catalytic systems (TCS) was examined. Two TCS were tentatively prepared in situ, adapting known methodologies: (a) Rh(C≡CPh)(norbornadiene)(PPh3) and (b) Rh(C(Ph)C=CPh2)(norbornadiene)(PPh3). Using the first TCS, the conjugated polymers poly 1 and poly 2 could be obtained in very good yields (77-86%), in short reaction times and freed from low molecular-weight products, only when NEt3 was used as a co-catalyst. With the second TCS, excellent results were obtained. Indeed, this catalytic system proved to be quite efficient in the polymerization of calix[4]arenes 1 and 2, affording the correspondent poly 1 and poly 2 essentially in almost quantitative yields (by GPC analysis), under appropriate conditions. The living nature of the polymerization has been proved. For instance, in the case of calix[4]arene 1, the Mn of the polymer obtained at high monomer conversion, increased proportionally with the [1]:[Rh] molar ratio in the feed, keeping [1]o constant, thus showing that irreversible chain transfer or termination reactions did not occur to a major extent. Under the most favorable conditions ([1]:[Rh]=50 and [2]:[Rh]=50), the polydispersities of poly 1 and poly 2 were kept in a narrow range (1.16-1.30).

Mots clés: Physical Sciences

José V. Prata. Studies Toward the Living Polymerization of Phenylethynyl-Calix[4]arene Compounds with Rh-based Ternary Catalytic Systems. Supramolecular Chemistry, 2008, 20 (01-02), pp.95-108. ⟨10.1080/10610270701762684⟩. ⟨hal-00513521⟩