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Compounds with bridgehead nitrogen: 45—the 1H NMR spectra and stereochemistry of some dimethylperhydro-oxazolo[3,4-a]pyridines

✍ Scribed by Trevor A. Crabb; Geoffrey C. Heywood

Publisher
John Wiley and Sons
Year
1982
Tongue
English
Weight
664 KB
Volume
20
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

The positions of conformational equilibria in 1,5‐, 1‐6‐ and 1,8‐dimethylperhydro‐oxazolo[3,4‐a]pyridines were determined by ^1^H NMR spectroscopy. The cis‐(H‐5, H‐8a)‐1,6‐dimethyl‐perhydro‐oxazolo[3,4‐a]pyridine. In contrast, r‐1,t‐6,t‐8a‐1,6‐dimethylperhydro‐oxazolo[3,4‐ a]pyridine preferred the cis‐fused conformation. Three of the 1,8‐dimethylperhydro‐oxazolo[3,4‐a]pyridines adopted the trans‐fused conformations (with distortion of the system in the case of the r‐1,c‐8,c‐8a derivative) and the r‐1,c‐8,t‐8a‐1,8‐dimethyl derivative adopted the cis‐fused conformation.

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