Antiaromatic Compounds, 23. - Cycloadditions of N-Acylimines to Cyclobutadienes
The cyclobutadienes 4a, b add the benzaldehyde imines 5a-c to yield the oxaazabicyclooctadienes 6a-e.Under thermal conditions (150-170 deg C) these isomerize in each case to 2-azabicyclohexenes (7a,c,d) and/or 8a,b,d,e) which differ only in
CYCLOADDITION OF N-ACYLIMINES WITH CYCLOBUTADIENES
N-Acylimines (2) possess the characteristics of both hetero-1,3-dienes and dienophyles.They react with the kinetically stabilised cyclobutadienes 1 to form 4-aza-2-oxabicycloocta-3,7-dienes (3) and/or 2-azabicyclohex-5-enes (4).Compounds of