Efficient, stereodivergent access to 3-piperidinols by traceless P(OEt)3 cyclodehydration
Peter H Huy1, Ari M P Koskinen
1Aalto University , School of Chemical Technology, Laboratory of Organic Chemistry, Kemistintie 1, 00076 Espoo, Finland.
Abstract:
A stereodivergent and highly diastereoselective (dr up to >19:1 for both isomers), step economic (5-6 steps), and scalable synthesis (up to 14 g) of cis- and trans-2-substituted 3-piperidinols, the core motif of numerous bioactive compounds, providing efficient access to the NK-1 inhibitor L-733,060 is presented. Additionally, a "traceless" (referring to the simplified byproduct separation) cyclodehydration realizing simple P(OEt)3 as a substitute for PPh3 is developed.
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