Synthesis and crystal structure of 2-(anthracen-9-yl)-1-(tert-butyl-dimethyl-sil-yl)-3,6-di-hydro-1λ4,2λ4-aza-borinine

Philipp J Gliese; Yannik Appiarius; Tarek Scheele; Enno Lork; Tim Neudecker; Anne Staubitz

doi:10.1107/S2056989023008381

Synthesis and crystal structure of 2-(anthracen-9-yl)-1-(tert-butyl-dimethyl-sil-yl)-3,6-di-hydro-1λ⁴,2λ⁴-aza-borinine

Acta Crystallogr E Crystallogr Commun. 2023 Oct 10;79(Pt 11):1012-1016. doi: 10.1107/S2056989023008381. eCollection 2023 Nov 1.

Authors

Philipp J Gliese^{1

2}, Yannik Appiarius^{1

2}, Tarek Scheele³, Enno Lork⁴, Tim Neudecker^{2

3

5}, Anne Staubitz^{1

2}

Affiliations

¹ University of Bremen, Institute for Organic and Analytical Chemistry, 28359 Bremen, Germany.
² University of Bremen, MAPEX Center for Materials and Processes, 28359 Bremen, Germany.
³ University of Bremen, Institute for Physical and Theoretical Chemistry, 28359 Bremen, Germany.
⁴ University of Bremen, Institute for Inorganic Chemistry and Crystallography, 28359 Bremen, Germany.
⁵ Bremen Center for Computational Materials Science, 28359 Bremen, Germany.

Abstract

The title compound, C₂₄H₃₀BNSi (I), is an asymmetric 1,2,3,6-tetra-hydro-1,2-aza-borinine consisting of a BN-substituted cyclo-hexa-diene analog with a B-anthracenyl substituent. A ring-closing metathesis with subsequent substitution of the obtained BCl 1,2-aza-borinine using anthracenyl lithium yielded the title compound I. The asymmetric unit (Z = 8) belongs to the ortho-rhom-bic space group Pbca and shows an elongated N-C bond compared to previously reported BN-1,4-cyclo-hexa-diene [Abbey et al. (2008 ▸) J. Am. Chem. Soc. 130, 7250-7252]. The primarily contributing surface inter-actions are H⋯H and C⋯H/H⋯C (as elucidated by Hirshfeld surface analysis) which are dominated by van der Waals forces. Moreover, the non-aromatic BN heterocycle and the protecting group exhibit intra- and inter-molecular C-H⋯π inter-actions, respectively, with the anthracenyl substituent.

Keywords: 1,2-azaborinine; BN cyclohexene; boron–nitrogen bond; boron–nitrogen heterocycle; crystal structure; ring-closing metathesis.

Grants and funding

Funding for this research was provided by: Deutsche Forschungsgemeinschaft (grant No. STA1195/2-1 to A. Staubitz); Deutsche Forschungsgemeinschaft (grant No. STA1526/3-1 to T. Neudecker).