Erythro and Threo Diastereomers CH2CH3 CH2CH CH3 CH3 H Br Br H H CI H H Br H —Br H OH HO H CH3 CH3 CH3 CH3 erythro threo erythro threo 2,3-dibromopentane 3-chloro-2-butanol ■ Erythro diastereomers have similar groups on the same side of the Fischer projection. Threo diastereomers have similar groups on opposite sides of the Fischer projection. Chapter 23 10Chapter 23 10 Erythro and Threo Diastereomers ▪ Erythro diastereomers have similar groups on the same side of the Fischer projection. ▪ Threo diastereomers have similar groups on opposite sides of the Fischer projection