Efficient, highly regioselective fries rearrangements of methyl 3-(2-acyloxy-4-methoxyphenyl)propanoates: The first total syntheses of the linear acylated coumarins geijerin and dehydrogeijerin.
作者:Nicholas Cairns、Laurence M. Harwood、David P.pp]Astles
DOI:10.1016/s0040-4039(00)80285-3
日期:1988.1
Aluminiumchloridecatalysed para-Fries rearrangement of methyl 3-(2-acyloxy-4-methoxyphenyl)propanoates (5)in nitromethane furnishes the corresponding 5-acylated products (6) cleanly and in high yield. The rearrangement products may be converted into 6-acyl-7-methoxycoumarins (2) including the naturally occurring geijerin (2a) and dehydrogeijerin (2b).
Paradkar, Madhusudan V.; Kulkarni, Madhuri S.; Kulkarni, Sanjeev A., Journal of Chemical Research - Part S, 1995, # 6, p. 262 - 263
作者:Paradkar, Madhusudan V.、Kulkarni, Madhuri S.、Kulkarni, Sanjeev A.、Godbole, Himanshu M.
DOI:——
日期:——
Syntheses of 6-acylcoumarins via highly regioselective fries rearrangements. Total syntheses of the linear acylated coumarins geijerin and dehydrogeijerin.
作者:Nicholas Cairns、Laurence M. Harwood、David P. Astles
DOI:10.1016/s0040-4020(01)90370-9
日期:1992.9
in general and efficient syntheses of 6-acylcoumarins. Under standard Fries rearrangement conditions (7) undergo highly regioselective para-migration with aluminiumchloride in nitromethane. The resulting C-acylated products (8) are converted into 6-acyl-7-methoxycoumarins (4). The scope and limitations of the rearrangement and the application to the total syntheses of the natural linear acylcoumarins