Total Synthesis of Granditropone, Grandirubrine, Imerubrine, and Isoimerubrine
摘要:
Concise total syntheses of the naturally occurring tropoloisoquinolines grandirubrine (1), imerubrine (2), and isoimerubrine (3) are detailed. The regioselective total synthesis of grandirubrine (1) is based on the [4 + 2] cycloaddition reaction of the alpha-pyrone 44 with the cyclopropenone ketal 18. Subsequent retro-Diels-Alder loss of CO2, norcaradiene rearrangement to the cycloheptatrienone ketal, and ketal hydrolysis provided the tropone 7 (granditropone). Regioselective hydroxylation of granditropone (NH2NH2; KOH) provided grandirubrine (1) and O-methylation of 1 provided both imerubrine (2) and isoimerubrine (3).
Total Synthesis of Granditropone, Grandirubrine, Imerubrine, and Isoimerubrine
摘要:
Concise total syntheses of the naturally occurring tropoloisoquinolines grandirubrine (1), imerubrine (2), and isoimerubrine (3) are detailed. The regioselective total synthesis of grandirubrine (1) is based on the [4 + 2] cycloaddition reaction of the alpha-pyrone 44 with the cyclopropenone ketal 18. Subsequent retro-Diels-Alder loss of CO2, norcaradiene rearrangement to the cycloheptatrienone ketal, and ketal hydrolysis provided the tropone 7 (granditropone). Regioselective hydroxylation of granditropone (NH2NH2; KOH) provided grandirubrine (1) and O-methylation of 1 provided both imerubrine (2) and isoimerubrine (3).
HIGHLY POLARIZED TROPONES. 9<i>H</i>-AZULENO[1,2,3-<i>ij</i>]NAPHTHALEN-9-ONE AND 8<i>H</i>-AZULENO[1,2,3-<i>ij</i>]NAPHTHALEN-8-ONE
作者:Kagetoshi Yamamoto、Yuji Matsue、Ichiro Murata
DOI:10.1246/cl.1981.1071
日期:1981.8.5
9H-Azuleno[l,2,3-ij]naphthalen-9-one (3a) and 8H-Azuleno [1,2 , 3-ij]naphthalen-8-one (3b), consisting of tropone and acenaphthylene have been synthesized. These ketones were found to be highly polarized and highly basic compounds.