Synthesis of [3]Rotaxanes that Utilize the Catalytic Activity of a Macrocyclic Phenanthroline-Cu Complex: Remarkable Effect of the Length of the Axle Precursor
[3]Rotaxanes, which consist of one macrocyclic phenanthroline compound and two axle components, were prepared by the oxidative dimerization of an alkyne compound with bulky tris[4′‐cyclohexyl‐(1,1′‐biphenyl)‐4‐yl]methyl blocking group. The catalyticactivity of a macrocyclicphenanthroline–Cucomplex was utilized to thread the two axle components inside the ring. The alkyne compound with chain of 15
Mechanically planar chiral [2]rotaxanes were synthesized by the introduction of bulky pyrrole moieties into the axle component of an achiral [2]rotaxane. The enantiomers were separated by chiral HPLC. The shuttling of the ring component between the two compartments at high temperature induced the stereoinversion of the mechanically planar chiral [2]rotaxane. The rate of the stereoinversion was studied
Synthesis of a Homochiral [2]Rotaxane from a BINOL-derived Macrocyclic Phenanthroline
作者:Shinichi Saito、Yoshihiro Hirano、Yuichiro Mutoh、Takeshi Kasama
DOI:10.1246/cl.150693
日期:2015.11.5
We synthesized a homochiral [2]rotaxane from a BINOL-derived macrocyclic phenanthroline. The catalytic activity of the BINOL-derived macrocyclic phenanthroline–Cu complex was utilized to promote the Glaser coupling reaction of a terminal alkyne, and a [2]rotaxane was isolated as a homochiral compound in 78% yield. The optical properties of the [2]rotaxane was examined by circular dichroism (CD) spectroscopy.
Rotacatenanes were synthesized by the catalytic reaction using a macrocyclic phenanthroline–CuI complex followed by the installation of another ring by the template method. In this approach, the size of the ring component of the rotaxane turns out to be a very important factor for the synthesis of rotacatenanes.
The catalytic activity of the macrocyclic phenanthroline-copper(1) complex is utilized for the Sonogashira-type reaction to synthesize [2]rotaxanes. Thus, [2]rotaxanes were prepared by reactions between terminal alkynes and aryl iodides in the presence of the macrocyclic copper complex. Bulky substituents were introduced to the substrates to stabilize the rotaxane. The bond-forming reaction proceeded selectively inside the macrocyclic complex so that the rotaxanes could be synthesized.