93455-38-0Relevant academic research and scientific papers
Synthetic and Stereochemical Aspects of Intramolecular Cycloadditions of N-Acyl Iminium Compounds with Alkene and Alkyne Dienophiles
Scola, Paul M.,Weinreb, Steven M.
, p. 3248 - 3250 (2007/10/02)
Boron trifluoride catalyzed intramolecular Diels-Alder cyclizations of N-acyl imines derived from simple aldehydes are stereospecific, affording trans-fused bicyclic 5,6-dihydro-1,3-oxazines.
Stereochemical Studies of Thermal Intermolecular and Intramolecular N-Sulfonylimine Ene Reactions
Tschaen, David M.,Turos, Edward,Weinreb, Steven M.
, p. 5058 - 5064 (2007/10/02)
N-Sulfonylimine 2 has been found to undergo highly stereoselective thermal ene reactions with cyclohexene and trans-2-butene.In the cyclohexene example, the exclusive product was unsaturated amino acid derivative 6, the product of an endo transition state.With trans-2-butene, a 9:1 mixture of 18:22 was obtained, with the endo product again predominating.Intramolecular ene processes have been effected with the N-sulfonylimines derived from glyoxylates 25c and 26c.In the former case, the sole ene product was γ-lactone 30 derived from exo addition.In the latter process, a 9:1 mixture of cis-(E)-lactone 32 and cis-(Z)-lactone 33 was produced.Lactone 32 results from endo ene transition state 35 and 33 results from endo transition state 36.All attempts to effect intermolecular ene reactions of N-benzoylimine 39 failed.In trying to perform an intramolecular N-acylimine ene reaction, only Diels-Alder adduct 45 was produced from precursor 42.
