A stereoselective and scalable synthesis of a conformationally constrained S1P1 agonist

A scalable and enantioselective synthesis of a potent S1P1 agonist containing two stereogenic centers on a cyclopentane ring is described. Control of the absolute chirality of an amino alcohol precursor, generated via a robust phase-transfer catalyzed alkylation protocol, allows for substrate directed hydrogenation to install the second stereogenic center providing access to gram-quantities of compound 2.