Praveen Prakash

Palladium/Lewis Acid Mediated Domino Reaction of Pentafulvene Derived Diazabicyclic Olefins: Efficient Access to Spiropentacyclic Motif with an Indoline and Pyrazolidine Fused to Cyclopentene

A palladium/Lewis acid mediated stepwise and one-pot transformation of pentafulvene derived diazabicyclic olefins is described. The reaction offers a facile strategy for the synthesis of novel spiropentacyclic motifs with indoline and pyrazolidine fused to the cyclopentene core.

Palladium catalyzed reaction of ortho-functionalized aryl iodides with bicyclic hydrazines: facile route toward heteroannulated cyclopentenes and azabicycles

Abstract A palladium catalyzed tandem protocol for the synthesis of cyclopentene fused heterocycles from diazabicyclic alkenes and ortho -functionalized aryl iodides has been elaborated. This tandem protocol was utilized for the synthesis of a number of cyclopentene fused dihydrobenzofurans and indolines. The reaction can be tuned toward the formation of either 3,4-disubstituted cyclopentenes or cyclopentene fused heterocycles by careful manipulation of the reaction parameters. The reaction was also extended to bicyclic alkenes derived from fulvene, which resulted in the heteroannulation of the azabicyclic system.

Mild rhodium(I) catalyzed ring opening of cyclopropane appended spirotricyclic olefins through C–H activation of arylboronic acids

Herein we describe a ligand free rhodium(I) catalyzed stereoselective ring-opening of cyclopropane appended spirotricyclic olefins through C–H bond cleavage of boronic acid. The developed methodology leads to the formation of aromatic molecules functionalized with trans-disubstituted spiro[2.4]hept-4-ene and cyclopropane appended spirotricyclic framework via 1,4-alkyl to aryl rhodium migration.

Lewis acid catalyzed C-3 alkylidenecyclopentenylation of indoles: an easy access to functionalized indoles and bisindoles

A Lewis acid catalyzed C-3 alkylidenecylopentenylation of indoles through the ring opening of pentafulvene derived diazabicyclic olefins has been developed. The present protocol offers an efficient route toward the synthesis of indole and bisindole derivatives. The role of the hydrazine group, as a reaction carrier in the strategy has also been demonstrated by the stepwise synthesis of functionalized bisindole.

CCDC 876343: Experimental Crystal Structure Determination

Related Article: Jubi John, Rani Rajan, S. Sarath Chand, Praveen Prakash, Nayana Joseph, Eringathodi Suresh, K.V. Radhakrishnan|2013|Tetrahedron|69|152|doi:10.1016/j.tet.2012.10.053