Versatile Reactivities of <i>ansa</i>-Heteroborabenzene Divalent Ytterbium Amide toward Alkali-Metal Salts and the Generation of Heterometallic Ytterbium−Alkali-Metal Boratabenzene Complexes

Reactions of the ansa-heteroborabenzene divalent ytterbium amide [C5H5BCH2(CH3)2P→BC5H5]YbN(SiMe3)2 (1) with alkali-metal salts (KC5Me5, NaOiPr, NaOAr, LiNHAr, LiN(SiMe3)2, LiNEt2, and KCH2Ar) were studied. The reaction of 1 with KC5Me5 caused a ligand displacement of neutral borabenzene by KC5Me5 at the Yb ion to give a heterometallic Yb−K boratabenzene complex with a polymeric structure, while that with NaOiPr caused a ligand displacement of the anionic amido ligand at the Yb ion by an isopropoxyl ligand to give a heterometallic Yb−Na boratabenzene complex with a polymeric structure. When LiNEt2 or KCH2Ar was employed as the reagent, the [NEt2]− or [CH2Ar]− group underwent nucleophilic attack at the B atom on the neutral borabenzene to cause the disassociation of the P→B coordination bond and the generation of new boratabenzene ligands.本研究系统考察了桥连杂硼苯二价镱酰胺配合物[C5H5BCH2(CH3)2P→BC5H5]YbN(SiMe3)2 (1)与多种碱金属盐（五甲基环戊二烯基钾(KC5Me5)、异丙醇钠(NaOiPr)、芳氧基钠(NaOAr)、芳基氨基锂(LiNHAr)、六甲基二硅基氨基锂(LiN(SiMe3)2)、二乙氨基锂(LiNEt2)及芳基甲基钾(KCH2Ar)）的反应行为。当该配合物1与五甲基环戊二烯基钾反应时，镱金属中心的中性硼苯配体被KC5Me5取代，得到具有聚合结构的异金属Yb-K硼杂苯配合物；而其与异丙醇钠反应时，镱中心的阴离子酰胺配体被异丙氧基配体取代，生成具有聚合结构的异金属Yb-Na硼杂苯配合物。当以二乙氨基锂(LiNEt2)或芳基甲基钾(KCH2Ar)作为反应试剂时，[NEt2]−或[CH2Ar]−基团会对中性硼苯上的硼原子发生亲核进攻，致使P→B配位键发生解离，并生成新型硼杂苯配体。