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Ringerweiterungsreaktionen von N ‐(2‐Aminoäthyl)‐, N ‐(4‐Aminobutyl)‐, N ‐(6‐Amino‐4‐aza‐hexyl)‐ und N ‐(8‐Amino‐4‐aza‐octyl)‐lactamen. 7. Mitteilung über Umamidierungsreaktionen
Author(s) -
Stephanou Euripides,
Guggisberg Armin,
Hesse Manfred
Publication year - 1979
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/hlca.19790620622
Subject(s) - chemistry , ring (chemistry) , lactam , stereochemistry , medicinal chemistry , organic chemistry
Ring Enlargement Reactions of N ‐(2‐Aminoethyl)‐ , N ‐(4‐Aminobutyl)‐ , N ‐(6‐Amino‐4‐aza‐hexyl)‐ and N ‐(8‐Amino‐4‐aza‐octyl)‐lactames The N ‐aminoalkyl‐lactams 1 , 3 , 4 , 10 (Scheme 2) and 13 (Scheme 3) have been synthesized. In the presence of KAPA (potassium 3‐aminopropylamide in 1,3‐propanediamine) 1 is stable, whereas 3 , 4 and 10 rearrange under ring enlargement to 5 , 8 and 11 , respectively. The 4‐aminobutyl derivate 13 rearranges in a fast reaction to 14 ; after a longer reaction time the 22membered ring 16 and the ring opened product 18 are formed. Hence it may be concluded that the 7membered lactam ring is more stable than the 10membered one, and the 11membered lactam ring is more stable than the 8 membered one. Moreover, the 5‐ and 6 membered ring intermediates of these transamidation reactions are prefered to the 7membered ring intermediates ( cf. [10]).