6881-76-1Relevant academic research and scientific papers
The 1-Aza-Cope Rearrangement
Wu, Pei-Lin,Chu, Min,Fowler, Frank W.
, p. 963 - 972 (2007/10/02)
The 1-aza-Cope rearrangement of azavinylcyclohexene derivatives were investigated.It was observed that an N-acyl substituent on the 1-aza 1,5-diene provides a sufficient driving force for this normally contrathermodynamic process.Although simple derivatives have high activation energies proceeding in relative low overall yield, a methoxy substituent at C-4 of the aza diene as well as its incorporation into strained bicyclic ring systems facilitates the 1-aza-Cope rearrangement.Because the aza diene precursors are readily available by using the Diels-Alder reaction with acrolein derivatives, this process has synthetic potential for the preparation of nitrogen heterocycles.This scheme is illustrated with the preparation of a hydrolulolidine providing a formal total synthesis of (+/-)-aspidospermine.
THE 1-AZA-COPE REARRANGEMENT
Chu, Min,Wu, Pei-Lin,Givre, Syndee,Fowler, Frank W.
, p. 461 - 464 (2007/10/02)
N-Acyl-1-aza-1,5-dienes participate in the Cope rearrangement.
Synthesis of Some Novel Functionalized Monoazatricyclic Ring Systems via Intramolecular Cycloaddition of N-(Bicycloalkenyl)nitrones
Eguchi, Shoji,Furukawa, Yoshio,Suzuki, Takanori,Kondo, Kazumoto,Sasaki, Tadashi,et al.
, p. 1895 - 1899 (2007/10/02)
The intramolecular cycloaddition of C-phenyl-N-(endo-bicyclooct-6-en-3-ylmethyl)nitrone (3) geneerated in situ from the corresponding hydroxylamine and benzaldehyde gave the adduct 4 in a high yield.Reductive cleavage of 4 afforded 2-endo-hydroxy-4-endo-phenyl-5-azatricyclo3,9>undecane (6).The intramolecular cycloadditions of unsymmetrical N-(endo-bicyclohept-5-en-2-ylmethyl)nitrones (11a,b) and N-(endo-bicyclooct-5-en-2-ylmethyl)nitrones (23a,b) occurred regiospecifically to afford the adducts 12a, b and 24a,b, respectively.Reductive cleavage of these adducts provided a convenient route to functionalized 5-azatricyclo3,8>decanes (15a,b, 16, 17) and 5-azatricyclo3,8>undecanes (27a,b, 28, 29), respectively.The regiochemical and stereochemical assignments of 12a and 24a were proven by X-ray analysis of the methiodides 14a and 26a.
