Asymmetric Syntheses by Optically Active Aminothiol Compounds. II

A simple asymmetric organocatalytic approach to optically active cyclohexenones.

Optically active 2,5-disubstituted-cyclohexen-2-one derivatives have been prepared in a one-pot process consisting of five reaction steps: an organocatalytic asymmetric conjugated addition of beta-ketoesters to alpha,beta-unsaturated aldehydes that proceeds in aqueous solutions or under solvent-free conditions has been implemented in a multi-step process.

Ultrahigh responsivity of optically active, semicondUcting asymmetric nanochannel diodes

LLE Review, Volume 143 167 Introduction Room-temperature nanodevices based on quantum confinement and/or ballistic nonlinearities are intrinsic nanostructures, not simply scaled-down conventional circuitry, and are gaining wide-spread research attention. Among the nanodevices, one of the most popular is the asymmetric nanochannel diode (ANCD), also referred to as a self-switching diode (SSD), f...

Optically Active Coordination Compounds. Part 50.' 4-Fold Symmetry Axes in Optically Active Complex Ions from Natural Nicotine

Optically active calixarenes conduced by methylene substitution.

The first method for the synthesis of optically active calix[4]arenes that are chiral as a result of substitution on the methylene bridges is described. The key step in the synthesis involves the reaction of a biscarbene complex with a diyne, which generates two of the benzene rings and the macrocyclic ring of the calix in a single transformation. The utility of this triple annulation process i...

Circula:r Dichroism of Optically Active 1,2-Disubstituted 1,2-Diphenyl Ethanes Part II: Compounds without COOR-group at Benzylic CY

(R,R)-Hydrobenzoin and homochirally analogous thTeo-compounds of formula Ph-CHX-CHY-Ph (X = Y; X rO Y; Y = H) show anegative O-O CD-line below 37200 crn? and/er a positive one just above it, which can be explained by conformational equilibria around the Ph-C bonds. The Cotton effect at 220-210 nm is negative for this same configuration, if X rO Y (also Y = H), in these other cases there no such...