Z. Szakonyi et al., SYNTHESIS AND RING-CHAIN TAUTOMERISM OF ANGULARLY SUBSTITUTED CYCLOALKANE-FUSED TETRAHYDRO-1,3-OXAZINES, Tetrahedron, 54(5-6), 1998, pp. 1013-1020
Starting from 1-methyl-1-cyclopentene and -cyclohexene, regioisomeric
1,3-amino alcohols 6a,b and 7a,b were prepared by regio-and stereospec
ific reactions. When the amino alcohols were condensed with aromatic a
ldehydes, well-defined products 8-11 were obtained, which exist as thr
ee-component tautomeric mixtures in CDCl3 solution. When equation (1)
was applied in all four sets 8-11, good linear correlations were obtai
ned. For regioisomeric compounds, introduction of the methyl group in
the bridgehead position resulted in reverse effects on the stability.
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