TY - JOUR
T1 - Intramolecular anionic Diels-Alder reactions of 1-aryl-4-oxahepta-1,6-diyne systems in DMSO
AU - Kudoh, Takayuki
AU - Mori, Tomoko
AU - Shirahama, Mitsuhito
AU - Yamada, Masashi
AU - Ishikawa, Teruhiko
AU - Saito, Seiki
AU - Kobayashi, Hisayoshi
PY - 2007/4/25
Y1 - 2007/4/25
N2 - Base-promoted cycloaddition reactions of 1-aryl- or 1-aryl-7-substituted-4- oxahepta-1,6-diyne systems in DMSO have proven to involve an anionic intramolecular Diels-Alder process taking place even at room temperature in spite of the reaction suffering from temporary disruption of aromaticity. Although initially formed α-arylallenide anion can be protonated by DMSO, it can be back to the allenide anion probably because of a small acidity difference between α-arylallene and DMSO. The α-arylallenide anion in combination with the α-aryl substituent can constitute an anionic diene structure that undergoes the intramolecular Diels-Alder reaction involving the C(6)-yne part, a very fast process probably because of the increased HOMO-1 level of the anionic diene, as shown by DFT calculations. Diversified substituted naphthalenes, benzofurans, phenanthrenes, and quinolines, including biaryl architectures, are available from 4-oxahepta-1,6-diynes in a highly expeditious way.
AB - Base-promoted cycloaddition reactions of 1-aryl- or 1-aryl-7-substituted-4- oxahepta-1,6-diyne systems in DMSO have proven to involve an anionic intramolecular Diels-Alder process taking place even at room temperature in spite of the reaction suffering from temporary disruption of aromaticity. Although initially formed α-arylallenide anion can be protonated by DMSO, it can be back to the allenide anion probably because of a small acidity difference between α-arylallene and DMSO. The α-arylallenide anion in combination with the α-aryl substituent can constitute an anionic diene structure that undergoes the intramolecular Diels-Alder reaction involving the C(6)-yne part, a very fast process probably because of the increased HOMO-1 level of the anionic diene, as shown by DFT calculations. Diversified substituted naphthalenes, benzofurans, phenanthrenes, and quinolines, including biaryl architectures, are available from 4-oxahepta-1,6-diynes in a highly expeditious way.
UR - http://www.scopus.com/inward/record.url?scp=34247471620&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=34247471620&partnerID=8YFLogxK
U2 - 10.1021/ja066485u
DO - 10.1021/ja066485u
M3 - Article
C2 - 17391030
AN - SCOPUS:34247471620
VL - 129
SP - 4939
EP - 4947
JO - Journal of the American Chemical Society
JF - Journal of the American Chemical Society
SN - 0002-7863
IS - 16
ER -