Niobium hydrido-olefin complexes, NbH(C5H5)2(olefin), are found to react readily with conjugated dienes such as butadiene, isoprene, and pentadiene, to give Nb(C5H5)2(η3-allyl) derivatives of syn or syn,syn geometry, in >80% yields with high regioselectivity. All the complexes were isolated as crystals and their structures were determined by NMR and EIMS spectroscopy. The reaction pathway leading to
铌氢化-烯烃络合物,NBH(C 5 H ^ 5)2(烯烃),被发现与共轭二烯如
丁二烯,
异戊二烯,
戊二烯和容易反应,得到的Nb(C 5 H ^ 5)2(η 3 -烯丙基)syn或syn,syn几何的衍
生物,> 80%的产率具有高区域选择性。分离出所有复合物为晶体,并通过NMR和EIMS光谱法测定其结构。反应途径,导致顺式-或顺式,顺式-η 3在产品的区域
化学和
氘标记实验的结果的基础上,对β-烯丙基
铌化合物进行了讨论。这些配合物容易与醛反应,在产物
水解时得到均烯丙基醇。发现相应的
钽衍
生物对所有测试的二烯是惰性的。