77879-82-4Relevant academic research and scientific papers
Formal total synthesis of (±)-herbertenediol and (±)-mastigophorenes A and B
Srikrishna, A.,Rao
, p. 5781 - 5782 (2001)
A simple and straightforward formal total synthesis of the sesquiterpene herbertenediol and its dimers mastigophorenes A and B, starting from vanillin, is described.
Boosting effect of ortho-propenyl substituent on the antioxidant activity of natural phenols
Marteau, Clémentine,Guitard, Romain,Penverne, Christophe,Favier, Dominique,Nardello-Rataj, Véronique,Aubry, Jean-Marie
, p. 418 - 427 (2015/10/19)
Seven new antioxidants derived from natural or synthetic phenols have been designed as alternatives to BHT and BHA antioxidants. Influence of various substituents at the ortho, meta and para positions of the aromatic core of phenols on the bond dissociation enthalpy of the ArO-H bond was evaluated using a DFT method B3LYP/6-311++G(2d,2p)//B3LYP/6-311G(d,p). This prediction highlighted the ortho-propenyl group as the best substituent to decrease the bond dissociation enthalpy (BDE) value. The rate constants of hydrogen transfer from these phenols to DPPH radical in a non-polar and non-protic solvent have been measured and were found to be in agreement with the BDE calculations. For o-propenyl derivatives from 2-tert-butyl-4-methylphenol, BHA, creosol, isoeugenol and di-o-propenyl p-cresol, fewer radicals were trapped by a single phenol molecule, i.e. a lower stoichiometric number. Reaction mechanisms involving the evolution of the primary phenoxyl radical ArO are proposed to rationalise these effects.
Synthesis of the landomycinone skeleton
Bugaut, Xavier,Guinchard, Xavier,Roulland, Emmanuel
supporting information; experimental part, p. 8190 - 8198 (2011/02/23)
The synthesis of the highly functionalized tetracyclic skeleton of landomycinone (2), the aglycon of landomycins, was performed using two pivotal steps relying on metal-catalyzed reactions. They are (1) a [2 + 2 + 2] cycloaddition of alkynes promoted by W
Total synthesis of (±)-herbertenediol
Srikrishna,Satyanarayana
, p. 2892 - 2900 (2007/10/03)
A formal total synthesis of the sesquiterpene (±)-herbertenediol and its dimers mastigophorenes A-D has been accomplished, starting from vanillin via 2,3-dimethoxy-5-methylbenzaldehyde. A combination of Claisen rearrangement and ring-closing metathesis reactions were employed for the generation of the two vicinal quaternary carbons on a cyclopentane ring.
Synthesis of chiral chromans by the Pd-catalyzed asymmetric allylic alkylation (AAA): Scope, mechanism, and applications
Trost, Barry M.,Shen, Hong C.,Dong, Li,Surivet, Jean-Philippe,Sylvain, Catherine
, p. 11966 - 11983 (2007/10/03)
The Pd-catalyzed asymmetric allylic alkylation (AAA) of phenol allyl carbonates serves as an efficient strategy to construct the allylic C-O bond allowing access to chiral chromans in up to 98% ee. The effect of pH and the influence of olefin geometry, as well as substitution pattern on the ee and the absolute configuration of the chiral chromans were explored in detail. These observations suggest a mechanism involving the cyclization of the more reactive π-allyl palladium diastereomeric intermediate as the enantiodiscriminating step (Curtin-Hammett conditions). This methodology led to the enantioselective synthesis of the vitamin E core, the first enantioselective total synthesis of (+)-clusifoliol and (-)-siccanin, and the synthesis of an advanced intermediate toward (+)-rhododaurichromanic acid A.
