摘要:

AbstractThe complete analysis of the1H NMR spectra of the six acetylated glycals as well as that of tetra‐O‐acetyl‐2‐hydroxy‐D‐glucal has been carried out. The conformation of these compounds, as determined from the proton couplings (±0.05Hz) obtained, has been interpreted in terms of a rapid interconversion equilibrium between the two possible dihydropyran half‐chair conformations. A computer treatment of all observed couplings has been carried out to obtain optimized values for the populations and couplings characteristic of the two alternative half‐chair conformations. The rotamer populations of the acetoxy–methyl group are discussed on the basis of the measured5J

ISSN:0030-4921    

DOI:10.1002/mrc.1270080112

出版商:John Wiley&Sons Limited    

年代:1976

数据来源: WILEY

摘要:

AbstractIt has been shown by NMR spectroscopy that both 4‐nitrobenzofurazan and 4‐nitrobenzofuroxan give isomeric σ‐adducts, which result from methoxide addition at the non‐substituted 5‐and

ISSN:0030-4921    

DOI:10.1002/mrc.1270080113

出版商:John Wiley&Sons Limited    

年代:1976

数据来源: WILEY

ISSN:0030-4921    

DOI:10.1002/mrc.1270080101

出版商:John Wiley&Sons Limited    

年代:1976

数据来源: WILEY