138385-69-0Relevant academic research and scientific papers
The nonplanar amide group in N-acylaziridines: Conformational behavior and chiroptical properties
Shustov,Kadorkina,Varlamov,Kachanov,Kostyanovsky,Rauk
, p. 1616 - 1623 (2007/10/02)
Chiroptical properties in the intrinsically dissymmetric amide chromophore of N-acylaziridines are investigated experimentally and by ab initio molecular orbital calculations. Computations on N-formylaziridine (1a) and measurements of the CD spectra of (1R,2R)-1-acetyl-2-methylaziridine (1b), (1A,2R)-1-(α-hydrohexafluoroisobutyryl)-2-methylaziridine (1c), (2′S)-1-(2′-methylbutyryl)aziridme (1d), and (2′S)-1-(2′-methylbutyryl)-2,2-dimethylaziridine (1e) suggest that the Cotton effect (CE) for the long wavelength absorption (band I) obeys a spiral rule: a right-handed twist of the O=C-N-C(ring) bonds corresponds to a negative CE for band I. Band I is assigned to the valence no-π* co transition. The next four higher energy absorptions are due to transitions to Rydberg states, nN-3s and nN-3p. Experimental CD spectra are also reported for the related compounds, (2′S)-1,2-bis(2′-methylbutyryl)-3,3-dimethyldiaziridine (2a), (αS)-1,2-diacetyl-3-sec-butyldiaziridine (2b), (2′S)-2-(2′-methylbutyryl)-3,3-dimethyloxaziridine (3a), (5S)-2-acetyl-5-methyl-1-oxa-2-azaspiro[2.5]octane (3b), (5)-N,N-dimethyl-2-methylbutyramide (4), and (2S)-1-(α-hydrohexafluoroisobutyryl)-2-methylazetidine (5).
