Practical Synthesis of 3-Oxa-6-azabicyclo[3.1.1]heptane Hydrotosylate; A Novel Morpholine-Based Building Block

Abstract

Bridged bicyclic morpholines are important building blocks in medicinal chemistry research. The bicyclic morpholine 3-oxa-6-azabicylo[3.1.1]heptane (3a) is of particular interest as a morpholine isostere because it is achiral and shows similar lipophilicity to that of morpholine, based on the cLogP of a derived analogue. The first synthesis of morpholine 3a (tosylate salt) is described; the seven-step sequence begins with inexpensive starting materials and uses straightforward chemistry.

Key words

isosteres - bicyclic compounds - heterocycles - cyclization - medicinal chemistry

• References

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