Ligand-controlled regiodivergent aminocarbonylation of cyclobutanols toward 1,1- and 1,2-substituted cyclobutanecarboxamides.

Four-membered carbocycles are among the most sought-after backbones which are commonly found in biologically active molecules. However, difficulties on their producing are existing due to its highly strained ring system. On the other hand, cyclobutanols can be straightforwardly prepared and can serves as precursors for synthesizing cyclobutane derivatives. Here we report an example of regioselective aminocarbonylation of cyclobutanols in which the cyclobutane core remained intact. The method exhibits good functional group compatibility, as well as high regio- and stereoselectivity, offering new pathways for synthesizing several pharmaceuticals. Furthermore, this strategy enables the rapid installation of cyclobutane as a conformational restricted skeleton, greatly facilitating direct access to valuable drug molecules that require conformational restriction.