Gold as Catalyst for the Hydroarylation and Domino Hydroarylation/N1–C4 Cleavage of β-Lactam-Tethered Allenyl Indoles
摘要:
Gold-catalyzed hydroarylation reaction of beta-lactam-tethered allenyl indoles gives azeto-oxepino[4,5-b]-indol-2-ones, tetrahydroazeto-azocino[3,4-b]indol-2-ones, and hexahydroazeto-azepino[3,4-b]indol-2-ones with very high levels of stereo, and regioselectivity, the 7-exo and 8-endo carbocyclization modes by attack of the indole group toward either the internal or the terminal allene carbon, respectively, being favored. Hydroarylation across the central carbon of the allene moiety has not been detected. The controlled gold-catalyzed annulations allowed the formation of fused beta-lactams without harming the sensitive four-membered heterocycle. Besides, a novel gold-catalyzed domino process, namely, the allenic hydroarylation/N1-C4 beta-lactam bond breakage to afford dihydro-oxepino[4,5-b]indole-4-carboxamides, has been discovered.
Application of Sequential Cu(I)/Pd(0)-Catalysis to Solution-Phase Parallel Synthesis of Combinatorial Libraries of Dihydroindeno[1,2-<i>c</i>]isoquinolines
作者:Sarvesh Kumar、Thomas O. Painter、Benoy K. Pal、Benjamin Neuenswander、Helena C. Malinakova
DOI:10.1021/co200027c
日期:2011.9.12
methodology is compatible with a wide-range of aliphatic linear, branched, and ester functionalized N-substituents. Unexpectedly, the formation of regioisomers featuring a 1,2,3-contiguous substitution pattern in the aromatic ring of the indene core was observed. Three distinct combinatorial libraries with a total of 111 of members were synthesized, and 80 highly substituted dihydroindenoisoquinolines structurally