Alternative approaches to (Z)-1,2-bis(2-bromopyridin-3-yl)ethenes, key intermediates in the synthesis of the 1,10-phenanthroline core

A study on the synthesis of (Z)-1,2-bis(2-bromopyridin-3-yl)ethenes, key intermediates in the preparation of 1,10-phenanthrolines, based on selective Sonogashira and Suzuki-Miyaura cross-coupling reactions has been carried out.