6533b855fe1ef96bd12afecb
RESEARCH PRODUCT
Photoinduced functionalization of diterpenes: photochemical behaviour of grandifloric acid in methanol and acetonitrile
Sergio RosselliFranco PiozziMaurizio BrunoNicolò VivonaLeonardo ScaglioniSilvestre Buscemisubject
PhotochemistryGeneral Chemical EngineeringCarboxylic groupGeneral Physics and AstronomyGeneral ChemistrySettore CHIM/06 - Chimica OrganicaNatural compoundPhotochemistrychemistry.chemical_compoundGrandiflorolic acidchemistrySurface modificationEpimerMethanolIrradiationGrandiflorolic acidAcetonitrileDiterpenedescription
Abstract Irradiation of grandiflorolic acid (11) at λ=254 nm in acetonitrile gave the two epimers 13 and 14 through a photodecarboxylation reaction of the carboxylic group on C-4. Irradiation of compound 11 in methanol at λ=254 nm provided the transformation of the C-20 angular methyl into a carbomethoxymethyl group. In this case, unlike compounds 13 and 14, only one of the two possible isomers (15) was obtained (equatorial methyl at C-4). A mechanistic approach of this reaction in discussed, and the role of mutual stereochemistry between C-20 methyl and C-19 carboxylic group in determining the course of the reaction is pointed out.
| year | journal | country | edition | language |
|---|---|---|---|---|
| 2004-03-01 |