One-Pot Synthesis of <i>B</i>-Aryl Carboranes with Sensitive Functional Groups Using Sequential Cobalt- and Palladium-Catalyzed Reactions

• Main Authors: Sergey A. Anufriev, Akim V. Shmal’ko, Kyrill Yu. Suponitsky, Igor B. Sivaev
• Format: Article
• Language: English
• Published: MDPI AG 2020-11-01
• Series: Catalysts
• Subjects: <i>ortho</i>-carborane; <i>B-</i>aryl derivatives; synthesis; Co/Pd catalysis; X-ray diffraction
• Online Access: https://www.mdpi.com/2073-4344/10/11/1348
• ISSN: 2073-4344

The simple and efficient method was developed for the one-pot synthesis of <i>B</i>-substituted aryl derivatives of <i>ortho</i>-carborane with functional groups sensitive to organolithium and organomagnesium reagents using 9-iodo-<i>ortho</i>-carborane and generated in situ organozinc compounds. The method proposed was used to prepare a series of 9-aryl-<i>ortho</i>-carboranes, including those containing nitrile and ester groups, 9-RC₆H₄-1,2-C₂B₁₀H₁₁ (R = <i>p</i>-Me, <i>p</i>-NMe₂, <i>p</i>-OCH₂OMe, <i>o</i>-OMe, <i>p</i>-OMe, <i>o</i>-CN, <i>p</i>-CN, <i>o</i>-COOEt, <i>m</i>-COOEt, and <i>p</i>-COOEt). It was demonstrated that the same approach can be used for synthesis of diaryl derivatives of <i>ortho</i>-carborane 9,12-(RC₆H₄)₂-1,2-C₂B₁₀H₁₀ (R = H, <i>p</i>-Me). The solid-state structures of 9-RC₆H₄-1,2-C₂B₁₀H₁₁ (R = <i>p</i>-NMe₂, <i>p</i>-OCH₂OMe, <i>o</i>-OMe, <i>o</i>-CN, <i>p</i>-CN, <i>m</i>-COOEt, and <i>p</i>-COOEt) and 9,12-(<i>p</i>-MeC₆H₄)₂-1,2-C₂B₁₀H₁₀ were determined by single crystal X-ray diffraction.