Insulated Molecular Wires: Dendritic Encapsulation of Poly(triacetylene) Oligomers, Attempted Dendritic Stabilization of Novel Poly(pentaacetylene) Oligomers, and an Organometallic Approach to Dendritic Rods
作者:Albertus P. H. J. Schenning、Jan-Dirk Arndt、Masato Ito、Alison Stoddart、Martin Schreiber、Peter Siemsen、Rainer E. Martin、Corinne Boudon、Jean-Paul Gisselbrecht、Maurice Gross、Volker Gramlich、François Diederich
DOI:10.1002/1522-2675(20010228)84:2<296::aid-hlca296>3.0.co;2-x
日期:2001.2.28
conditions (Scheme 6). The synthesis of dendritic PPA oligomers by oxidative coupling of (E)-enetetrayne 60 under end-capping conditions provided oligomers 61a – d, which were formed as mixtures of stereoisomers due to unexpected thermal (E)(Z) isomerization (Scheme 8). In another novel approach towards dendritic encapsulation of molecular wires with a Pt-bridged tetraethynylethene (TEE) oligomeric
具有树枝状侧链的多纳米长的封端聚 (三乙炔) (PTA) 和聚 (五乙炔) (PPA) 低聚物被合成为绝缘分子线。通过 Mitsunobu 反应和随后的 Glaser-Hay 低聚反应将树突(分别为 8、13 和 17,方案 1)连接到(E)-烯二炔 18 上,制备了具有横向附加 Frechet 型树突的第一代至第三代 PTA 低聚物在封端条件下(方案 2)。虽然分离了直到五聚体的第一代低聚物(1a - e),但由于空间拥挤,在第二代水平上只形成了直到三聚体(2a - c)的低聚物,并且只有封端的单体和二聚体(3a,b)在第三代水平上分离。通过重复的氢化硅烷化序列(使用 Karstedt 催化剂),随后进行烯丙基化或乙烯基化,还制备了一系列碳硅烷树突(方案 3 和 4)。第二代楔形物 40 与 (E)-烯二炔 18 的连接,然后是脱保护和随后的封端 Hay 齐聚,为 PTA 齐聚物 4a-d