(1R,2R)-rel-2-Methoxycyclopentanecarboxaldehyde is used in the synthesis of dl-9-Deoxyprostaglandin E1; Also, it is the trans isomer of (1R,2S)-rel-2-Methoxycyclopentanecarboxaldehyde (M312170), which is derived from Methyl 2-Cyclopentanonecarboxylate (M294705), which is used in the synthesis of functionalized ketones.