Synthesis of Cyclic 1,2‐Bisphosphines by Tandem Michael Addition of 2,3‐Bis(diarylphosphinyl)‐1,3‐butadiene.

A base‐promoted tandem Michael addition of malonates to 2,3‐ bis(diarylphosphinyl)‐1,3‐butadienes was developed for the synthesis of cyclopentyl 1,2‐bisphosphine compounds. This method enables rapid construction of various 1,2‐bis(diarylphosphinyl)cyclopentanes, and features readily accessible reactants, mild conditions and good functional group tolerance. The product could be easily transformed to the corresponding transition metal complexes, which may find broad applications in asymmetric catalysis. [ABSTRACT FROM AUTHOR]