An Unusual Reaction of Methyl 3,5-Dimethoxybenzoate with Thallium(III)Trinitrate - Trifluoro Acetic Acid

Thallium(III)trinitrate trihydrate (TTN) is known to be a useful and extremely versatile reagent in organic synthesis.^1-5 Its use has been exploited mainly in oxidation and oxidative rearrangements of chalcones, aromatic ketones and phenols. In this communication, we report an unusual reaction of polyoxygenated methylbenzoates with TTN.     

Y-branch - the key component for crosstalk reduced optical switches: modelling analysis

A novel design method for switching devices is demonstrated based on waveguide structures with Y-branches and abrupt waveguide changes as key elements. A combination of BPM calculation and eigenmode analysis is shown to be a promising tool to obtain deep insight into the physical mode behaviour. Based on the analysis, a mode converter to match the eigenmodes in amplitudes and phase can be developed and introduced as a correcting device. This method is demonstrated for the crosstalk compensation of a digital switch (DOS) and a Δβ-reversal switch. A crosstalk of about −20 dB can be reduced to −40 dB by this method. This revised version was published online in November 2006 with corrections to the Cover Date.     

Regiospecific oxidation by DDQ of unhindered alkyl groups in sterically hindered aromatic amines

DDQ oxidises an unhindered activated alkyl group to a carbonyl or a hydroxymethyl group depending on the nature of the substitution, in a sterically hindered aromatic amine.