Efficient Synthesis of Fluorescent Squaraine Rotaxane Dendrimers
摘要:
A squaraine rotaxane scaffold with four alkyne groups is readily converted into a range of dendritic architectures using high-yielding copper-catalyzed alkyne azide cycloaddition (CuAAC) chemistry. A convergent synthesis approach is more efficient than a divergent pathway. Dendritic squaraine rotaxanes with peripheral amine groups can be further functionalized to produce multivalent deep-red fluorescent derivatives that exhibit high brightness and outstanding chemical stability in biological solution. The surface groups on these functionalized fluorescent dendrimers include guanidinium, mannose, and phosphatidylcholine.
Closer to the “Ideal Recoverable Catalyst” for Atom Transfer Radical Polymerization Using a Molecular Non-Fluorous Thermomorphic System
作者:Guillaume Barré、Daniel Taton、Dominique Lastécouères、Jean-Marc Vincent
DOI:10.1021/ja048096a
日期:2004.6.1
complex CuBr/1 was shown to catalyze the atomtransferradicalpolymerization of methyl methacrylate with good control of the molar masses and polydispersities. Due to the thermoresponsive character of CuBr/1 polymerizations were carried out in homogeneous conditions while lowering the temperature to 10 degrees C led to the precipitation of the catalyst. Catalyst recovery was achieved with high yield