Fused Five and Six Ring Nitrogen Systems

Heimbach, B. Hugelin, H. Peter, A. Roloff, and E. Troxler, Angew. Chem. Internat. Edn., 

Rodebaugh, M. Grippi, G. DeVicaris, C. Hyndman, and J. Marakowski, 

The hasubanan skeleton (243) has been prepared in 90% yield by the alkylation of the amine (242) with formaldehyde and formic acid the synthesis resembles the Sommelet reaction and the authors offer the plausible mechanism shown. 

Two papers by Chow s group have provided routes to useful structural types. Model and -alkenyl nitrosamines were synthesized and photolysed 

Intramolecular regioselective cycloadditions with unactivated olefins have been described by Sammes and Watt. Thermolysis of the pyridine betaine (254) at 

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Fused Five and Six Ring Nitrogen Systems.—The acid catalysed reactions of alkyli-dene bisurethanes with conjugated dienes gave various azacyclic and azabicyclic molecules formed by 1,4 (or 1,6)-addition to the conjugated system by the acylimine (241). > In new work the first example of a formal 1,3-cycIoaddition during the reaction of (241) with dienes has been observed (Scheme 107). 

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