Catalytic transformations of non-stabilized carbenes


Carbenes are versatile reactive intermediates that display orthogonal reactivity to common nucleophilic and electrophilic functional groups. Homogeneously catalyzed carbene transfer reactions were first discovered over a half century ago, and numerous examples of cycloaddition reactions have now been developed, often with control over diastereo- and enanatioselectivity. Nearly all of these reactions rely on the controlled decomposition of diazoalkane precursors as a central strategy for accessing reactive carbene equivalents.

Despite the utility of diazoalkanes in organic synthesis, they are inherently limited by the need for stabilizing substituents such as aryl or carbonyl groups. In order to develop transfer reactions of non-stabilized carbenes, such as methylene, isopropylidene, and vinylidene, it would be necessary to identify an alternative set of precursors. Here, we show that nickel and cobalt catalysts can promote reductive cycloaddition reactions using readily available and indefinitely stable 1,1-dichloroalkanes and 1,1-dichloroalkenes as carbene precursors. The development of new asymmetric methods and mechanistic insights into these reactions will be presented.

Presenter

Speaker Image for Christopher Uyeda
Purdue University

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