Organo‐Iodine(III)‐Catalyzed Oxidative Phenol–Arene and Phenol–Phenol Cross‐Coupling Reaction

The direct oxidative coupling reaction has been an attractive tool for environmentally benign chemistry. Reported herein is that the hypervalent iodine catalyzed oxidative metal‐free cross‐coupling reaction of phenols can be achieved using Oxone as a terminal oxidant in 1,1,1,3,3,3‐hexafluoropropan‐2‐ol (HFIP). This method features a high efficiency and regioselectivity, as well as functional‐group tolerance under very mild reaction conditions without using metal catalysts.     

One‐Pot Sequence‐Controlled Synthesis of Oligosiloxanes

Silicones (organopolysiloxanes) have found applications in a wide range of research areas, and their unique and valuable properties have rendered these materials virtually irreplaceable. Despite the fact that silicones have been employed industrially for more than 70 years, synthetic routes to generate silicones remain limited, and the sequence‐controlled synthesis of oligo‐ and polysiloxanes still represents a major challenge in silicone chemistry. Described here is a highly selective sequence‐controlled synthesis of linear, branched, and cyclic oligosiloxanes by simple iteration of two reactions, specifically, a B(C₆F₅)₃‐catalyzed dehydrocarbonative cross‐coupling of alkoxysilanes with hydrosilanes and a B(C₆F₅)₃‐catalyzed hydrosilylation of carbonyl compounds, in a single flask. The sequence of the resulting oligosiloxanes can be controlled precisely by the order of addition of the hydrosilane monomers.     

Intramolecular Diels-Alder reaction of selenoaldehydes

Intramolecular Dieis-Alder reaction of selenoaldehydes which were generated from bis(trimethylsilyl) selenide and dienals gave the corresponding bicyclic adducts.     

Fully k-Primary Rings

Let k be a positive integer. The structure of rings all of whose ideals are n-primary for some positive integer n ≤ k is studied, and several examples of such rings are constructed. Rings all of whose nonzero ideals are n-primary for some positive integer n ≤ k is also considered.     

Young's double-slit interference observation of hot electrons in semiconductors

We have carried out Young's double-slit experiment for the hot-electron wave in man-made semiconductor structures with a 25-nm-space double slit in an InP layer buried within GaInAs, a 190-nm-thick GaInAsP hot-electron wave propagation layer, and a collector array of 80 nm pitch. At 4.2 K, dependences of the collector current on the magnetic field were measured and found to agree clearly with the double-slit interference theory. The present results show evidence for the wave front spread of hot electrons using the three-dimensional state in materials, for the first time, and the possibility of using top-down fabrication techniques to achieve quantum wave front control in materials.