Hydrogen and halogen bonding in the haloetherification products in chalcone

Cooperative action of hydrogen and halogen bonding in the reaction of 3-(3,5-di-tert-butyl-4-hydroxyphenyl)-1-phenylprop-2-en-1-one with HCl or HBr in alcohol medium under microwave irradiation (20 W, 80 °C, 10 min) allows the isolation of the haloetherification products (2S,3S)-3-(3-tert-butyl-5-chloro-4-hydroxyphenyl)-2-chloro-3-ethoxy-1-phenylpropan-1-one, C 21 H 24 Cl 2 O 3 , (2S,3S)-2-bromo-3-(3-tert-butyl-5-bromo-4-hydroxyphenyl)-3-methoxy-1-phenylpropan-1-one, C 20 H 22 Br 2 O 3 , and (2S,3S)-2-bromo-3-(3-tert-butyl-5-bromo-4-hydroxyphenyl)-3-ethoxy-1-phenylpropan-1-one, C 21 H 24 Br 2 O 3 , in good yields. Both types of noncovalent interactions, e.g. hydrogen and halogen bonds, are formed to stabilize the obtained products in the solid state. © 2019 International Union of Crystallography.