迈向多股分子导线：[上键 1 开始]Pt-C(x)-Pt-(P(CH2)3P)2-Pt-C(x)-Pt-(P(CH2)3P[上键 1 结束])2 核（x = 4, 6, 8）的四铂双（多炔二基）配合物的合成、结构和反应性。

Towards multistranded molecular wires: syntheses, structures, and reactivities of tetraplatinum bis(polyynediyl) complexes with [upper bond 1 start]Pt-C(x)-Pt-(P(CH2)3P)2-Pt-C(x)-Pt-(P(CH2)3P[upper bond 1 end])2 cores (x = 4, 6, 8).

机构信息

Institut für Organische Chemie and Interdisciplinary Center for Molecular Materials, Friedrich-Alexander-Universität Erlangen-Nürnberg, Henkestrasse 42, 91054, Erlangen, Germany.

出版信息

Dalton Trans. 2010 Jun 14;39(22):5260-71. doi: 10.1039/c002041a. Epub 2010 May 7.

DOI:10.1039/c002041a

PMID:20454708

Abstract

Reactions of trans,trans-(C(6)F(5))(p-tol(3)P)(2)Pt(C[triple bond]C)(n)Pt(Pp-tol(3))(2)(C(6)F(5)) (PtC(x)Pt; x = 2n) and the 1,3-diphosphine Ph(2)P(CH(2))(3)PPh(2) (2.5 equiv) give the tetraplatinum complexes trans, trans,trans,trans-(C(6)F(5))[upper bond 1 start]Pt(C[triple bond]C)(n)Pt(C(6)F(5))(PPh(2)(CH(2))(3)Ph(2)P)(2)(C(6)F(5))Pt(C[triple bond]C)(n)Pt(C(6)F(5))(PPh(2)(CH(2))(3)Ph(2)P[upper bond 1 end])(2) (Pt'C(x)Pt'; x = 4/6/8, 39%/95%/81%). Crystal structures of Pt'C(8)Pt' and two solvates of Pt'C(6)Pt' are determined. These confirm that each diphosphine spans two platinum atoms from different Pt(C[triple bond]C)(n)Pt linkages, as opposed to (1) the 1,2-diphosphine Ph(2)P(CH(2))(2)PPh(2), which under similar conditions with PtC(8)Pt affords the diplatinum bis(chelate) cis,cis-([upper bond 1 start]PPh(2)(CH(2))(2)Ph(2)P)(C(6)F(5))Pt[upper bond 1 end](C[triple bond]C)(4)[upper bond 1 start]Pt(C(6)F(5))(PPh(2)(CH(2))(2)Ph(2)P[upper bond 1 end]) (73%) or (2) alpha,omega-diphosphines with longer methylene chains, which span the platinum termini. The formulation Pt'C(4)Pt' is supported by a reaction with PEt(3) (10 equiv) to give trans,trans-(C(6)F(5))(Et(3)P)(2)Pt(C[triple bond]C)(2)Pt(PEt(3))(2)(C(6)F(5)). In Pt'C(8)Pt' and one solvate of Pt'C(6)Pt', the chains cross at 77.2 degrees-87.7 degrees angles, with the closest interchain carbon-carbon distances (3.27-3.61 A) less than the sum of the van-der-Waals radii. In the other solvate of Pt'C(6)Pt', the chains are essentially parallel, and the separation is much greater (4.96 A). UV-visible spectra show no special electronic interactions. However, cyclic voltammograms indicate irreversible oxidations, in contrast to the partially reversible oxidations of PtC(6)Pt and PtC(8)Pt. The initially formed radical cations are proposed to undergo rapid chain-chain coupling. The new complexes decompose without melting above 185 degrees C. With Pt'C(8)Pt', IR spectra indicate the formation of a new C[triple bond]C-rich substance.

摘要

反式, 反式-(C(6)F(5))(p-甲苯膦)(2)Pt(C[三键]C)(n)Pt(Pp-甲苯膦)(2)(C(6)F(5)) (PtC(x)Pt; x = 2n) 和 1,3-二膦基 Ph(2)P(CH(2))(3)PPh(2) (2.5 当量) 生成四铂配合物反式, 反式, 反式, 反式-(C(6)F(5))[上键 1 开始]Pt(C[三键]C)(n)Pt(C(6)F(5))(PPh(2)(CH(2))(3)Ph(2)P)(2)(C(6)F(5))Pt(C[三键]C)(n)Pt(C(6)F(5))(PPh(2)(CH(2))(3)Ph(2)P[上键 1 结束])(2) (Pt'C(x)Pt'; x = 4/6/8, 39%/95%/81%). Pt'C(8)Pt' 和 Pt'C(6)Pt' 的两个溶剂化物的晶体结构被确定。这些结构证实，每个二膦基跨越两个来自不同 Pt(C[三键]C)(n)Pt 键的铂原子，而不是 (1) 1,2-二膦基 Ph(2)P(CH(2))(2)PPh(2)，在类似条件下与 PtC(8)Pt 生成二铂双螯合顺式, 顺式-([上键 1 开始]PPh(2)(CH(2))(2)Ph(2)P)(C(6)F(5))Pt上键 1 结束(4)[上键 1 开始]Pt(C(6)F(5))(PPh(2)(CH(2))(2)Ph(2)P[上键 1 结束]) (73%) 或 (2) 具有更长甲基链的 α,ω-二膦基，它们跨越铂端。Pt'C(4)Pt'的表述得到与 PEt(3) (10 当量) 反应的支持，得到反式, 反式-(C(6)F(5))(Et(3)P)(2)Pt(C[三键]C)(2)Pt(PEt(3))(2)(C(6)F(5))。在 Pt'C(8)Pt' 和 Pt'C(6)Pt' 的一个溶剂化物中，链在 77.2 度-87.7 度角交叉，最近的链间碳-碳距离 (3.27-3.61 A) 小于范德华半径之和。在 Pt'C(6)Pt' 的另一个溶剂化物中，链基本平行，分离距离更大 (4.96 A)。紫外可见光谱显示没有特殊的电子相互作用。然而，循环伏安法表明不可逆氧化，与 PtC(6)Pt 和 PtC(8)Pt 的部分可逆氧化形成对比。最初形成的自由基阳离子被提议进行快速链链偶联。新配合物在 185 度以上分解而不熔化。对于 Pt'C(8)Pt'，红外光谱表明形成了一种新的 C[三键]C 丰富的物质。