8π-Six-atom rings: 1,3,4,5-oxa- and -thia-triazines and 1,2,3,5-tetrazines from an extended tandem reaction: reactions of 1,2,3-triazolium-1-imides with (E)-cinnamaldehyde, methyl cyanodithioformate, and aryl-N-sulphinylamines: new tetrahydro-oxazolo[4,5-d]-1,2,3-triazoliumides and triazaspiro-[4.4]nonanes. Azolium 1,3-dipoles. Part 4

1990; Issue: 9 Linguagem: Inglês

10.1039/p19900002527

ISSN

2050-8255

Autores

Richard N. Butler, Ann M. Evans, Eithne M. McNeela, Gerard A. O'Halloran, Paul O’Shea, Desmond Cunningham, Patrick McArdle,

Tópico(s)

Synthesis and Reactions of Organic Compounds

Resumo

The reactions of substituted 1,2,3-triazolium-1-imides with (E)-cinnamaldehyde, methyl Cyanodithioformate, and aryl-N-sulphinylamines gave rise to substituted 1,3,4,5-oxatrizines, 1,3,4,5-thiatriazines, and 1,2,3,5-tetrazines, respectively. Each of these is an 87π-six-atom ring. The routes were similar in each case and involved an extended tandem sequence of cycloaddition, rearrangement, fragmentation, and ring expansion. New oxazolo[4,5-d]-1,2,3-triazoles which were formed along the route to the 1,3,4,5-oxatriazines were isolated as stable compounds. The structures and reactivity of the 8π-six-atom rings are discussed. X-Ray crystal structures are reported for 4-(p-bromophenyl)-2,6-diphenyl-4H-1,3,4,5-oxatriazine (6b); 2,4,6-triphenyl-4H-1,3,4,5-thiatriazine (11a); 5-(p-bromophenyl)-2,5-dihydro-2,4,6-triphenyl-1,2,3,5-tetrazine (17b); 2,6-bis(p-bromophenyl)-3a,5,6,6a-tetrahydro-3a,6a-diphenyl-5exo-styryloxazolo[4,5-d]-1,2,3-tri-azol-2-ium-1-ide (4b); and 4-[(5′-methylisoxazol-3′-yl)imino]-2-(p-nitrophenyl)-1,2,3-triazaspiro[4.4]non-1-en-2-ium-3-ide (19b).

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