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2,3-Dihydro-1H-inden-1-one derivatives were synthesized by a [5+2−2] decarbonylative cycloaddition of 1H-indene-1,2,3-trione and norbornene via rhodium(I) catalyzed direct carbon–carbon bond cleavage. A catalytic system combining [Rh(COD)Cl]2 (5.0 mol%) and rac-BINAP(10 mol%) ligand was optimal for these transformations. Various functional groups were tolerated under standard reaction conditions. Although the reactions in most of the cases showed no regioselectivity, some substrates with a –OMe, –CN, or strong electron-withdrawing –CF3 group at the 4-position displayed high regioselectivity. [ABSTRACT FROM AUTHOR]