Dual role of Reformatsky reagent was disclosed to synthesis 1,2-dihydroisoquinolines
Our research group have been focused on development of novel synthetic transformation to achieve the biologically important heterocyclic molecules. In ongoing research, we disclosed the dual role of Reformatsky reagent to the synthesis of 1,2-dihydroisoquinolines via 6-endo-digcyclisation, without aid of any external Lewis acid catalyst. Similarly, cobalt catalysed nitro-Mannich reaction was reported using an o-alkynylarylaldimines to afford 1,2-dihydroisoquinolines.
Base catalysed 5-enolexo-dig cyclisation to achieve the substituted indenes
Thesynthetic pathway for functionalizedindenes was investigated. The reaction was proceeds with catalytic base via a Michael-addition-cyclization sequence. The synthetic pathway involves a 5-enolexo-ding cyclization and stereoselectivity form a cis isomer and trans-isomer for cyclopenta[b]quinolines, albeit the presence of steric hindrance at quaternary carbon.
Protecting-group -directed domino Michael-addition-Mannich cyclization to synthesize diastereoselective tetrahydropyrrloquinolines
Protecting-group-directed synthesis of tetrahydro-3H-pyrrolo-[2,3-c]-quinolines that bear four contiguous chiral centers was described with highdiastereoselectivity (≥30:1). The reaction underwent the domino Michael-addition-Mannich cyclisation pathway to afford the products in good to excellent yield. Protecting groups in the substates play the role to achieve the diastereoselectivity in products formation.
