New aniline containing aminoalcohols from trans (R,R) 2-(2-nitrophenyl)-3-phenyloxirane as useful intermediates for the synthesis of chiral ligands, bases and benzoxazines

New enantiopure aniline-containing amino alcohols are directly derived from trans-(R,R)-2-(2-nitrophenyl)-3-phenyloxirane,by alternative regioselective double reductions. Subsequent selective alkylation procedures and derivatizations provide a rapid and high-yielding access to different chiral ligands, bases, and benzoxazines, without loss of optical purity

A mild Stereo- and Enantiospecific Conversion of 2,3-Diaryl-Substituted Oxiranes into 2,2-Dimethyl-1,3-Dioxolanes by an Acetone/Amberlyst 15 System

Amberlyst 15 is an efficient catalyst for the reaction of aryl-substituted oxiranes with acetone to prepare 2,2-dimethyl- 1,3-dioxolanes in high yields. trans-2,3-Diaryloxiranes afford trans-acetonides enantiospecifically at room temperature, and the use of enantiopure 2,3-diaryloxiranes results in no loss of stereochemical integrity in the resulting trans-acetonides

Non-Destructive Extraction of Semiconducting Single Walled Carbon Nanotubes by Wrapping with Flexible Porphyrin Polypeptides and the Supramolecular Photodynamics

International audienc

(R)-(+)- and (S)-(–)-1-(9-Phenenantryl)ethylamine: Assignment of Absolute Configuration by CD Tweezer and VCD Methods, and Difficulties Encountered with the CD Exciton Chirality Method

In agreement with predictions from the stereochemical outcome of pyruvate hydrogenation with chiral 1-(9-phenanthryl)ethylamine (1), the (+) isomer (as measured in CHCl3) was assigned the (R) configuration by use of the Zn-porphyrin host-guest CD exciton chirality method after derivatization with 4-[(Boc-amino)methyl]pyridine-2-carboxylic acid, and also directly on the amine by use of the VCD method. Attempts to use the bis(chromophoric) CD exciton chirality method after derivatization with a naphthimido group happened to be more difficult because of the complex electronic structure of the phenanthryl group, although the naphthimido moiety was the most suitable chromophore in this case. The results are discussed

(R)-(+)- and (S)-(-)-1-(9-Phenanthryl)ethylamine: Assignment of Absolute Configuration by CD Tweezer and VCD Methods, and Difficulties Encountered with the CD Exciton Chirality Method

In agreement with predictions from the stereochemical outcome of pyruvate hydrogenation with chiral 1-(9-phenanthryl)ethylamine (1), the (+) isomer (as measured in CHCl3) was assigned the (R) configuration by use of the Zn-porphyrin host-guest CD exciton chirality method after derivatization with 4-[(Boc-amino)methyl]pyridine-2-carboxylic acid, and also directly on the amine by use of the VCD method. Attempts to use the bis(chromophoric) CD exciton chirality method after derivatization with a naphthimido group happened to be more difficult because of the complex electronic structure of the phenanthryl group, although the naphthimido moiety was the most suitable chromophore in this case. The results are discussed