Mono(boratabenzene) rare-earth metal dialkyl complexes: synthesis, structure and catalytic behaviors for styrene polymerization. Issue 12 (25th February 2015)

• Record Type: Journal Article
• Authors: Wang, Xiufang; Leng, Xuebing; Chen, Yaofeng
• Is Part Of: Dalton transactions. Volume 44:Issue 12(2015)
• Page Start: 5771
• Page End: 5776
• Publication Date: 2015-02-25
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c4dt04043k
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : Synthesis and structural characterization of mono(boratabenzene) rare-earth metal dialkyl complexes were achieved by using multi-substituted boratabenzene ligands, and the synthesized scandium complexes show high catalytic activities for syndiotactic styrene polymerization upon activation with cocatalysts. Abstract : Four mono(boratabenzene) rare-earth metal dialkyl complexes, [(3, 5-Me2 -C5 H3 BR)Ln(CH2 SiMe3 )2 (THF)] (1 : R = NEt2, Ln = Sc;2 : R = NEt2, Ln = Lu;3 : R = Ph, Ln = Sc;4 : R = Ph, Ln = Lu), were synthesized efficiently via a one-pot strategy with Li[ 3, 5-Me2 -C5 H3 BR] (R = NEt2, Ph), LnCl3 (THF) x (Ln = Sc, x = 3; Ln = Lu, x = 0), and LiCH2 SiMe3 . The solid-state structures of1 and2 were determined by single-crystal X-ray diffraction. Variable-temperature NMR studies indicated that the energy barrier for the rotation of aminoboratabenzene in1 (Δ G ‡ ≈ 71 kJ mol −1 ) is higher than that of phenylboratabenzene in3 (Δ G ‡ ≈ 59 kJ mol −1 ). These mono(boratabenzene) rare-earth metal dialkyl complexes' catalytic behaviors for styrene polymerization were investigated, and found that mono(boratabenzene) scandium dialkyl complexes show high catalytic activities for syndiotactic polymerization upon activation with cocatalysts.