Synthesis of pterocarpan-type heterocycles via oxidative cycloadditions of phenols and electron-rich arenes
Oxidation of 4-alkoxyphenols or 4-methoxynaphthol with phenyl iodonium(bis)trifluoroacetate (PIFA) in the presence of electron rich 2H-chromenes or dihydronaphthalenes affords pterocarpans or 5-carbapterocarpans via a formal [3+2] cycloaddition process. A
Mohr, Amber L.,Lombardo, Vincent M.,Arisco, Teresa M.,Morrow, Gary W.
experimental part
p. 3845 - 3855
(2009/12/06)
Silver-catalyzed asymmetric synthesis of 2,3-dihydrobenzofurans: A new chiral synthesis of pterocarpans
2,3-Dihydrobenzofurans can be diastereoselectively prepared by condensation of aromatic aldehydes with 2,3-dihydrobenzoxasilepines under the catalysis of Ag1 complexes, and in the presence of a source of fluoride ion. The application of this st
Formal 2 + 2 and 3 + 2 cycloaddition reactions of 2H-chromenes with 2-alkoxy-1,4-benzoquinones: Regioselective synthesis of substituted pterocarpans
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Engler,Reddy,Combrink,Vander Velde
p. 1248 - 1254
(2007/10/02)
Syntheses of Pterocarpans, I. - Synthesis of Both the Enantiomers of Pterocarpin
The first synthesis of (-)-pterocarpin (6) was achieved by resolving (+/-)-2, which in turn was prepared from a known isoflavone (1).Unnatural (+)-pterocarpin was also synthesized.