Synthesis of chiral 3-substituted 3-amino-2-oxindoles through enantioselective catalytic nucleophilic additions to isatin imines

• Hélène Pellissier

Beilstein J. Org. Chem. 2018, 14, 1349–1369, doi:10.3762/bjoc.14.114

• imines published since the beginning of 2015. Keywords: asymmetric synthesis; chiral 3-amino-2-oxindoles; chirality; isatin imines; nucleophilic addition; Introduction Chiral oxindoles represent an important class of products widely present in nature and exhibiting many biological activities. Among

• 2015 by Enders et al. at a remarkably low catalyst loading (0.0225 mol %) to promote the enantioselective Mannich reaction of ethyl nitroacetate (2) with N-Boc-isatin imines 3 [35]. The process afforded, after a subsequent denitration, the corresponding chiral 3-amino-2-oxindoles 4 in moderate to high

• products were converted into useful intermediates for the synthesis of pyrroloindoline alkaloids and related drugs, such as psychotrimine and (+)-folicanthine. Later in 2016, Trivedi et al. reported the synthesis of chiral 3-amino-2-oxindoles through the Mannich reaction of N-Boc-isatin imines 3 with 1,3

Organocatalytic asymmetric allylic amination of Morita–Baylis–Hillman carbonates of isatins

• Hang Zhang,
• Shan-Jun Zhang,
• Qing-Qing Zhou,
• Lin Dong and
• Ying-Chun Chen

Beilstein J. Org. Chem. 2012, 8, 1241–1245, doi:10.3762/bjoc.8.139

• yields (up to 97%). Keywords: allylic amination; asymmetric organocatalysis; Morita–Baylis–Hillman carbonates; 2-oxindoles; quaternary chiral center; Introduction Chiral 3-amino-2-oxindoles are versatile and useful units for the preparation of natural products and drug candidates, such as the

• ][28], as outlined in Scheme 1. Thus, multifunctional chiral 3-amino-2-oxindoles could be obtained in a straightforward manner. Results and Discussion Based on the above considerations, we initially investigated the reaction of MBH carbonate 2a and a diversity of nucleophilic nitrogen sources by the