Fig. 3. Molecular structure of compound 11b (thermal ellipsoids are shown with 50% probability). Selected bond lengths (Å) and angles (°): B1–O1 1.524(3), B2–O2 1.524(3), O1–C41 1.301(2), O2–C48 1.303(2), C41–C42 1.432(3), C42–C47 1.421(3), C47–C48 1.441(3), C48–C49 1.425(3), C49–C54 1.423(3), C54–C41 1.445(3), B1–O1–C41 134.5(2), B2–O2–C48 136.0(2), C54–C41–O1–B1 –135.8(2), and C47–C48–O2–B2 –145.2(2).
