Synthesis of a Six‐Membered‐Ring (2R)‐10a‐Homobornane‐10a,2‐sultam and Structural Comparison with Oppolzer's,Lang's,and King's Sultams |
| |
Authors: | Anna Pitek Christian Chapuis Janusz Jurczak |
| |
Abstract: | The new six‐membered‐ring (2R)‐10a‐homobornane‐10a,2‐sultam (?)‐ 3a was synthesized and its X‐ray structural analysis was compared with that of the novel structure of the five‐membered‐ring (2R)‐bornane‐10,2‐sultam analogues (?)‐ 1a , b as well as with that already published for the six‐membered‐ring trans‐decalin‐like sultam 4a . Based on DN** density‐function calculations and X‐ray crystallographic studies of the N‐methylated analogues (?)‐ 1e and 4b and by comparing with the conformation of the N‐fluoro derivatives (?)‐ 1c and (+)‐ 1d , the anomeric stabilization was estimated to be smaller than the 2.0–2.5 kcal/mol earlier suggested. The direction of pyramidalization is rationalized in terms of H‐bond and steric and electronic interactions and extended to the known toluenesultam derivatives 10a – c . |
| |
Keywords: | |
|
|