Synthesis, characterisation and optical properties of metal-containing polydiacetylenes
Abstract
Soluble polydiacetylenes (CR–CC–CR′
)n[R = R′=(CH2)9O2CCH2Ph (2a); R =(CH2)9CH3, R′=(CH2)8CO2CH2Ph (2b)] have been synthesized and reacted with Co2(CO)8 to introduce varying proportions of Co2(CO)6 groups, attached as Co2C2 tetrahedrane units, at the alkyne bonds of the conjugated ene–yne backbone. These metallated polymers have been characterised by analytical data and by IR, 13C[1H] NMR and UV–VIS spectroscopy. Reactions between polydiacetylenes 2a or 2b and [M2(CO)4(η5-C5H5)2](M = Mo, W) are also reported. The presence of fast optical non-linearities in these soluble polymeric materials was confirmed by fluorescence lifetime measurements and optical characterisation of the imaginary part of χ(3) These studies were conducted on a picosecond timescale to allow electronic contributions to be resolved, and the related lm χ(3) values tabulated against metal content and solution concentration.