A systematic study directed towards the preparation of metal acetylide oligomers of the formula [-CºC-Ar-CºC-M(L)m-]n via a palladium-catalysed Extended One Pot (EOP) synthetic protocol has shown that, for M = Pt, Pd, palladium catalysis leads to the selective formation of bistinacetylydes Bu3Sn-CºC-Ar-CºC-SnBu3 (Ar = C6H4, C6H2(3,6-bis-OC8H17)). The coupling of the latter compounds with Cl2M(L)2 (M = Pt, Pd) to form metal acetylide oligomers is a thermally activated process that efficiently takes place, yielding short oligomers, only in the absence of any palladium catalyst. The GPC technique has proved to be a reliable method to estimate the chain lengths of polymers bearing branched aromatic spacers, despite the rigid-rod shape of their backbone. Single crystal X-ray determinations of model compounds have demonstrated the fundamental role of the side substituents in the aryl spacers to control the supramolecular order of the oligomeric materials.
Metal Acetylide Oligomers as Building Blocks for the Engineering of Molecular Devices
Masi D;Bianchini C;
2003
Abstract
A systematic study directed towards the preparation of metal acetylide oligomers of the formula [-CºC-Ar-CºC-M(L)m-]n via a palladium-catalysed Extended One Pot (EOP) synthetic protocol has shown that, for M = Pt, Pd, palladium catalysis leads to the selective formation of bistinacetylydes Bu3Sn-CºC-Ar-CºC-SnBu3 (Ar = C6H4, C6H2(3,6-bis-OC8H17)). The coupling of the latter compounds with Cl2M(L)2 (M = Pt, Pd) to form metal acetylide oligomers is a thermally activated process that efficiently takes place, yielding short oligomers, only in the absence of any palladium catalyst. The GPC technique has proved to be a reliable method to estimate the chain lengths of polymers bearing branched aromatic spacers, despite the rigid-rod shape of their backbone. Single crystal X-ray determinations of model compounds have demonstrated the fundamental role of the side substituents in the aryl spacers to control the supramolecular order of the oligomeric materials.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
