Efficient construction of diverse spiro[indoline-3,4′-pyrrolo[3,4-<i>b</i>]pyridines] <i>via</i> [3 + 3] cycloaddition of MBH carbonates of isatins with β-enamino maleimides

Abstract

]pyridine-8,3'-indolines] in good yields and with lower diastereoselectivity. The relative configuration of the two diasteromers of the spiro compounds was clearly elucidated by the determination of eight single crystal structures.