A radical annulation, i.e. an intermolecular radical Michael addition followed by an intramolecular Michael addition of the resultant radical (radical cyclisation) has been employed for the construction of chiral functionalised bicyclo[3.3,1]-nonanes. Thus reaction of carvone hydrohalides 7 with (n)Bu(3)SnH and AIBN in the presence of excess of radicophiles 4 furnished, regiospecifically bicyclo[3.3.1]nonanes 8-14, introducing three new chiral centres in a stereoselective manner. Analogously the bromide 18 generated the bridgehead substituted bicyclo[3.3.1]-nonanes 19-21.
FeCl<sub>3</sub> Catalyzed Prins-Type Cyclization for the Synthesis of Highly Substituted Indenes: Application to the Total Synthesis of (±)-Jungianol and <i>epi</i>-Jungianol
作者:Dattatraya H. Dethe、Ganesh Murhade
DOI:10.1021/ol3032347
日期:2013.2.1
A novel approach was developed for the synthesis of highly substituted indene derivatives, using an FeCl3 catalyzed Prins-type cyclization reaction which was further applied in the total synthesis of jungianol and epi-jungianol.
SRIKRISHNA, ADUSUMILLI;SHARMA, G. VEERA RAGHAVA;HEMAMALINI, PARTHASARATHY, J. CHEM. SOC. CHEM. COMMUN.,(1990) N3, C. 1681-1683
作者:SRIKRISHNA, ADUSUMILLI、SHARMA, G. VEERA RAGHAVA、HEMAMALINI, PARTHASARATHY
DOI:——
日期:——
Silver(I)-Catalyzed Ring-Contractive Rearrangement: A New Entry to 5-Alkylidene-2-cyclopentenones
A novel silver(I)-catalyzed ring-contractive rearrangement of 5-substituted 6-diazo-2-cyclohexenones has been developed, providing a new and efficient access to 5-alkylidene-2-cyclopentenones. The AgOTf-catalyzed reaction proceeds through metal–carbenoid formation followed by endocyclic allyl [1,2] migration with excellent stereoselectivity and broad substrate scope.