Synthesis, characterization, and crystal structure of 2′,2″-dihydroxy-3,3‴-bichalcone and its related chalcone–flavanone and biflavanone analogs

The synthesis of 3,3′-diformyl-1,1′-biphenyl 1 and its reaction in basic media with 2′-hydroxyacetophenone and paeonol, respectively, are described. The products, a bichalcone 2, it’s partially cyclized analog, a flavanone–chalcone 3 and the fully cyclized biflavanone 4, are reported as products for the first reaction, while only the chalcone 5 for the second. The crystalline and molecular structure, solved by X-ray diffraction analysis, for compounds 2 and 5 are also presented in this work.