Active-metal template clipping synthesis of novel [2]rotaxanes.

Mechanically interlocked molecules (MIMs) have been important synthetic targets in supramolecular chemistry due to their beautiful structures and intriguing properties. We present herein a new synthetic strategy to access [2]rotaxanes, namely active-metal template clipping. We discuss the design of the target [2]rotaxanes, synthesis and characterization of the axle, macrocycle precursors and macrocycles as well as preparation of the final [2]rotaxanes by active template copper(I)-catalyzed alkyne-azide cycloaddition (CuAAC) as key step of the synthesis.

Bulky Polyfluorinated Terphenyldiphenylboranes: Water Tolerant Lewis Acids.

Protocols for the synthesis of the bulky polyfluorinated triarylboranes 2,6-(C F ) C F B(C F ) (1), 2,6-(C F ) C F B[3,5-(CF ) C H ] (2), 2,4,6-(C F ) C H B(C F ) (3), 2,4,6-(C F ) C H B[3,5-(CF ) C H ] (4) were developed. All boranes are water tolerant and according to the Gutmann-Beckett method, 1-3 display Lewis acidities larger than that of the prominent B(C F ) .