Synthesis and crystal structure of 2-(anthracen-9-yl)-1-( tert -butyl-dimethyl-sil-yl)-3,6-di-hydro-1λ 4 ,2λ 4 -aza-borinine.

The title compound, C 24 H 30 BNSi ( 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.