Distance-Triggered Distinct Aryl Migrations on Azidodiboranes

Tong-Tong Liu; Jiaxin Chen; Bing-Tao Guan; Zhenyang Lin; Zhang-Jie Shi

doi:10.1002/chem.202203676

Distance-Triggered Distinct Aryl Migrations on Azidodiboranes

Chemistry. 2023 Mar 1;29(13):e202203676. doi: 10.1002/chem.202203676. Epub 2023 Jan 19.

Authors

Tong-Tong Liu¹, Jiaxin Chen², Bing-Tao Guan¹, Zhenyang Lin², Zhang-Jie Shi^{1

3}

Affiliations

¹ Department of Chemistry, Fudan University, Shanghai, 200438, P. R. China.
² Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, P. R. China.
³ State Key Laboratory of Organometallic Chemistry, Shanghai Institute of Organic Chemistry, CAS, Shanghai, 200032, P. R. China.

PMID: 36446733
DOI: 10.1002/chem.202203676

Abstract

Derived from structurally similar precursors, two different azidodiboranes went through distinct aryl migration reactions triggered by different boron-boron separation distances. Biphenylene based diborane with a shorter boron-boron distance underwent heterolateral aryl migration to form a seven-membered azadiborepin, while xanthrene based diborane with a longer boron-boron distance afforded a stable bis-azidoborane scaffold. The pyrolysis of such a bis-azidoborane led to eight-membered oxazadiborocine through homolateral aryl migration and subsequent [3+2] cycloaddition. Density functional theory (DFT) calculations unveiled that the boron-boron separation distances were the intrinsic factors for the distinct migrations.

Keywords: azidoborane; bisborane; iminoborane; migration; synergistic effect.

Abstract

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