A phosphine mediated sequential annulation process of 2-tosylaminochalcones with MBH carbonates to construct functionalized aza-benzobicyclo[4.3.0] derivatives.

A novel phosphine mediated sequential annulation process to construct functionalized aza-benzobicyclo[4.3.0] derivatives has been developed involving a one-pot sequential catalytic and stoichiometric process, which generates a series of benzobicyclo[4.3.0] compounds containing one quaternary center with up to 94% yield and 20 : 1 dr value. In this reaction, MBH carbonates act as 1,2,3-C3 synthons.