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
Shah et al., Journal of Scientific & Industrial Research, 1956, vol. 15 B, p. 580
作者:Shah et al.
DOI:——
日期:——
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).