Mechanistic investigations aided by isotopic labeling. 10. Investigations of novel furan-2,3-dione rearrangements by oxygen-17 labeling
- Karl Franzens Univ., Graz (Austria)
The oxa 1,3-diene moiety in 4-benzoyl-5-phenylfuran-2,3-dione (1) adds aryl isocyanides or heterocumulenes via formal (4 + 1) or (4 + 2) cycloaddition processes. The unstable primary adducts undergo novel furandione rearrangements to intermediates in which the two oxygen atoms of the lactone moiety in (1) are equivalent. This equivalence was confirmed by {sup 17}O-labeling experiments using {sup 17}O NMR spectroscopic and mass spectroscopic measurements. Comparison of the {sup 17}O chemical shifts in (1), labeled either at the benzoyl and ring oxygens (1a-{sup 17}O) or at both exocyclic ring-carbonyl oxygens (1b-{sup 17}O), with those in the products (2-4) confirmed the proposed pathways of these rearrangements. Reactions involving carbodiimides, isocyanates, and ketene imines were investigated.
- OSTI ID:
- 7237525
- Journal Information:
- Journal of Organic Chemistry; (United States), Journal Name: Journal of Organic Chemistry; (United States) Vol. 56:1; ISSN JOCEA; ISSN 0022-3263
- Country of Publication:
- United States
- Language:
- English
Similar Records
Biosynthesis of the modified peptide antibiotic nosiheptide in Streptomyces actuosus
Labeled phosphonic acid compositions for investigations of in vivo deposits of calcium
Related Subjects
400201* -- Chemical & Physicochemical Properties
400202 -- Isotope Effects
Isotope Exchange
& Isotope Separation
CHEMICAL REACTION KINETICS
DATA
EVEN-ODD NUCLEI
EXPERIMENTAL DATA
INFORMATION
ISOTOPES
KINETICS
LABELLED COMPOUNDS
LABELLING
LIGHT NUCLEI
MAGNETIC RESONANCE
NUCLEAR MAGNETIC RESONANCE
NUCLEI
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC OXYGEN COMPOUNDS
OXYGEN 17
OXYGEN ISOTOPES
REACTION KINETICS
RESONANCE
STABLE ISOTOPES