thunberginol G dimethyl ether;monomethylphylodulcin;3-(3,4-dimethoxy-phenyl)-8-hydroxy-isochroman-1-one;3-(3,4-Dimethoxy-phenyl)-8-hydroxy-isochroman-1-on;Thunberginol H;3-(3,4-dimethoxyphenyl)-8-hydroxy-3,4-dihydroisochromen-1-one
Titanocene(III) chloride mediated radical-induced synthesis of 3,4-dihydroisocoumarins: synthesis of (±)-hydrangenol, (±)-phyllodulcin, (±)-macrophyllol and (±)-thunberginol G
摘要:
A radical-promoted synthesis of 3,4-dihydroisocoumarins has been achieved in moderate to good yields using titanocene(III) chloride (Cp2TiCl) as the radical initiator. The total synthesis of four naturally occurring dihydrocoumarins hydrangenol, phyllodulcin, macrophyllol and thunberginol G has been accomplished using the radical technology. Cp2TiCl was prepared in situ from commercially available titanocene dichloride (Cp2TiCl2) and Zn-dust in THF under argon. (C) 2008 Elsevier Ltd. All rights reserved.