Stepwise Asymmetric Allylic Substitution‐Isomerization Enabled Mimetic Synthesis of Axially Chiral B,N‐Heterocycles

• Published in: Angewandte Chemie 2022-12, Vol.134 (51), p.n/a
• Main Authors: Zhang, Xiu‐Lian, Gu, Jun, Cui, Wen‐Hao, Ye, Zhiwen, Yi, Wenbin, Zhang, Qiang, He, Ying
• Format: Article
• Language: English
• Subjects: Asymmetric Allylic Substitution-Isomerization; Asymmetry; Atropisomerism; Axial Chirality; B,N-Heterocycles; Chemical synthesis; Chemistry; Chirality; Density functional theory; Isomerization; Mimetic Synthesis; Organic chemistry; Stereoisomerism; Stereoisomers; Substitutes
• ISSN: 0044-8249; 1521-3757
• DOI: 10.1002/ange.202210456

Axially chiral molecules bearing multiple stereogenic axes are of great importance in the field of organic chemistry. However, the efficient construction of atropisomers featuring two different types of stereogenic axes has rarely been explored. Herein, we report the novel atroposelective synthesis of configurationally stable axially chiral B,N‐heterocycles. By using stepwise asymmetric allylic substitution‐isomerization (AASI) strategy, diaxially chiral B,N‐heterocycles bearing B−C and C−N axes that are related to the moieties of axially chiral enamines and arylborons were also obtained. In this case, all four stereoisomers of diaxially chiral B,N‐heterocycles were stereodivergently afforded in high enantioselectivities. Density functional theory (DFT) studies demonstrated that the NH⋅⋅⋅π interactions played a unique role in the promotion of stereospecific isomerization, thereby leading to the highly efficient central‐to‐axial chirality transfer. By means of stepwise asymmetric allylic substitution‐isomerization (AASI) strategy, diaxially chiral B,N‐heterocycles bearing B−C and C−N axes that are related to the moieties of axially chiral enamines and arylborons were obtained. Density functional theory (DFT) studies demonstrated that the NH⋅⋅⋅π interactions played a unique effect on the promotion of stereospecific isomerization.