N→Sn-Coordinated Stannaoxidoborates Containing a SnB₄O₆ Unit

Abstract

We report here the synthesis of new N→Sn-coordinated stannaoxidoborates H[LSnB4O6R4] {L = [2,6-(Me2NCH2)C6H3](-) and R = Ph (6), 4-Br-Ph (7), 3,5-(CF3)2-Ph (8), and 4-CHO-Ph (9)} containing a nonsymmetric SnB4O6 unit. Compounds 6-9 represent new derivatives of the pentaborates [B5O6R4](-) in which the central boron is substituted by a tin atom. Compounds 6-9 were characterized by means of elemental analysis, electrospray ionization mass spectrometry, and NMR spectroscopy and in the case of 6-8 also by single-crystal X-ray diffraction analysis. The structures of N→Sn-coordinated stannaoxidoborates 6-8 consist of a spirobicyclic arrangement, with two six-membered SnB2O3 rings at the tin atom providing the new stannaoxidoborate [LSnB4O6R4](-) motif, which is compensated for by the proton atom coordinated to the Me2N group of the ligand L. The linear and thermal properties of 6-9 were studied with the help of electronic absorption spectra and differential scanning calorimetry. In addition, the presence of the nonsymmetric stannaoxidoborate SnB4O6 unit in 6, 7, and 9 prompted us to investigate their second-order nonlinear-optical properties.

Applications of boroxide ligands in supporting small molecule activation by U(iii) and U(iv) complexes

“…Boroxines are rigid bidentate ligands which have drawn attention recently, mostly by forming complexes of main group elements, e.g. for Al; [38][39][40] Sn, Sb and Bi; [41][42][43][44][45][46][47] but also for transition metals such as Mn, 48 Au 37,49 and Pt. 50 Single crystals of 5 m and 6 m were obtained by slow diffusion of hexanes into a benzene solution.…”

(N),C,N‐Coordinated Heavier Group 13–15 Compounds: Synthesis, Structure and Applications

“…The presence of the Ar NCN ligand containing two nitrogen atoms is crucial for the isolation of these compounds. While one nitrogen is involved in the N→Sn coordination, the second one serves as a base in deprotonation of boronic acids (Scheme ) . The stannaoxidoborates contain non‐symmetric SnB 4 O 6 unit with spiro‐bicyclic arrangement consisting of two six‐membered stannaboroxine SnB 2 O 3 rings (Scheme ).…”