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Proton magnetic resonance studies of compounds with bridgehead nitrogen: XXVIII—Stereochemical studies with perhydropyrido[1,2-c] [1,6,3]dioxazocines and 2-alkylperhydropyrido[1,2-c] [1,3,6]oxdiazocines

✍ Scribed by Trevor A. Crabb; Graham C. Jackson

Publisher
John Wiley and Sons
Year
1975
Tongue
English
Weight
745 KB
Volume
7
Category
Article
ISSN
0749-1581

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✦ Synopsis

Abstract

A series of perhydropyrido[1,2‐c][1,6,3]dioxazocines and 2‐alkylperhydropyrido[1,2‐c][1,3,6]oxdiazocines have been prepared. 6‐p‐Nitrophenyl‐3,4‐dimethylperhydropyrido[1,2‐c][1,6,3]‐dioxazodioxazocine is shown to adopt the cis fused ring conformation in solution with the nitrogen lone pair axial with respect to the piperidine ring. The 2‐alkylperhydropyrido[1,2‐c][1,3,6]oxdiazocines adopt a similar cis fused ring conformation and with increasing steric requirement of the 2‐alkyl substituent the 8‐membered ring increasingly favours the chair‐chair conformation, rather than the chair–boat conformation favoured by the 2‐methyl substituted compound.

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