A review of the total syntheses of triptolide

• Xiang Zhang,
• Zaozao Xiao and
• Hongtao Xu

Beilstein J. Org. Chem. 2019, 15, 1984–1995, doi:10.3762/bjoc.15.194

• the formal synthesis of triptolide (Figure 2, route N) [43]. This synthesis highlighted the palladium-catalyzed asymmetric addition of arylboronic acid 37 to 3-methylcyclohex-2-en-1-one (38) to form the C-10 quaternary chiral center, and a subsequent Claisen rearrangement and an aldol reaction to

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

• isatins to obtain 2-oxindoles bearing a C3-quaternary chiral center, by the catalysis of chiral tertiary amines, β-isocupreidine (β-ICD) or its derivatives [23][24]. We envisaged that such a catalytic strategy should be applicable to the allylic amination of the corresponding MBH carbonates [25][26][27

• provides an electrophilic process to 3-amino-2-oxindoles with a C3-quaternary chiral center. A range of products with high molecular complexity were obtained with good to excellent enantioselectivity (up to 94% ee) and high yields (up to 97%). Currently, more studies on the catalytic asymmetric