Department of Chemistry and Vanderbilt Institute of Chemical Biology, Vanderbilt University, Nashville, TN 37235-1822, USA.
Angew Chem Int Ed Engl. 2010 Mar 22;49(13):2290-8. doi: 10.1002/anie.200904828.
A new means to activate diazoalkanes has been discovered and applied broadly over the past few years. Brønsted acids, both achiral and chiral, have been used to promote the formation of carbon-carbon and carbon-heteroatom bonds with a growing number of diazoalkane derivatives. Aside from their straightforward ability to build structural and stereochemical complexity in innovative new ways, these transformations are remarkable owing to their ability to skirt competitive diazo protonation--a reaction that has long been used to prepare esters efficiently and cleanly from carboxylic acids. In cases where achiral Brønsted acids are used, high diastereoselection can be achieved. Meanwhile, chiral Brønsted acids can deliver products with both high diastereo- and enantioselectivity. More recently, systems have emerged that combine Brønsted acids and either Lewis acids or transition metals to promote carbon-carbon bond formation from diazoalkanes.
在过去的几年中，人们发现并广泛应用了一种将重氮烷烃激活的新方法。布朗斯特酸（无论是手性的还是非手性的）已被用于促进越来越多的重氮烷烃衍生物与碳-碳和碳-杂原子键的形成。除了它们以创新的新方式构建结构和立体化学复杂性的直接能力外，这些转化引人注目，因为它们能够规避竞争性的重氮质子化反应——长期以来，该反应一直被用于从羧酸高效且清洁地制备酯。在使用非手性布朗斯特酸的情况下，可以实现高非对映选择性。同时，手性布朗斯特酸可以提供具有高对映选择性和非对映选择性的产物。最近，出现了一些将布朗斯特酸与路易斯酸或过渡金属结合使用的系统，以促进重氮烷烃的碳-碳键形成。
