Selecting reactions and reactants using a switchable rotaxane organocatalyst with two different active sites.
نویسندگان
چکیده
The activation mode of a rotaxane-based organocatalyst with both secondary amine and squaramide catalytic units can be switched with acid or base. The macrocycle blocks whichever of the catalytic sites it is positioned over. The switchable rotaxane catalyst generates different products from a mixture of three building blocks according to the location of the macrocyclic ring in the rotaxane.
منابع مشابه
Selecting reactions and reactants using a switchable rotaxane organocatalyst with two different active sites† †Electronic supplementary information (ESI) available: Synthetic procedures and characterisation data. See DOI: 10.1039/c4sc03279a Click here for additional data file.
Synthetic catalysts have previously been developed where a stimulus can be used to turn the catalytic activity ‘on’ or ‘off’ or to change the stereochemical outcome of a reaction. Here we report on an articial system that can switch between two different modes of organocatalysis, each promoting a different chemical transformation. The result is a molecular catalyst that can be used to produce ...
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ورودعنوان ژورنال:
- Chemical science
دوره 6 1 شماره
صفحات -
تاریخ انتشار 2015