✍ Scribed by Ritter, Joachim ;Gleiter, Rolf
No coin nor oath required. For personal study only.
The reactions of 1,6‐dialkyl‐1,6‐diazacyclodeca‐3,8‐diynes (9, a = CH~3~, b = C~2~H~5~, c = i‐C~3~H~7~) with HCl, H~2~O and CH~3~OH have been investigated. The reaction of 9c with HCl selectively gives N,N′‐diisopropyl‐4‐chloro‐1,2,3,5,6,7‐hexahydro‐2,6‐naphthyridine (13c) in quantitative yield. Investigation of this reaction at different temperatures allows the activation parameters for the process to be derived (Δ__H__^≠^ = 24 ± 1 kcal · mol^−1^, Δ__S__^≠^ = – 9 ± 2 cal · mol^−1^ · K^−1^). The regioselective reaction of 9c with methanol affords a quantitative yield of N,N′‐diisopropyl‐4‐methoxy‐1,2,3,4,5,6,7‐hexahydro‐2,6‐naphthyridine (29c). Addition of water to 9a in the presence of H~2~SO~4~ gives N,N‐dimethyl‐7‐oxo‐1,2,3,4,5,6,7,8‐octahydro‐2,6‐naphthyridine (28a) in low yields (15%). If the addition of water is carried out in the presence of Hg^2+^, the yield of 28a is increased considerably. The mechanisms of all three reactions are discussed and those involving electrophilic addition (Ad~E~2) are favored.
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## Abstract For Abstract see ChemInform Abstract in Full Text.
Chiral Allyl Cations in Cycloadditions to Furan: Synthesis of 2-(1'-Phenylethoxy)-8-oxabicyclo[3.2.1]oct-6-en-3-one in High Enantiomeric Purity. -The new diastereo-and enantioselective route to the title compound (III) uses chiral 1-phenylethanol as both a convenient chiral auxiliary and a protecti