A Chemical/Computational Approach to the Determination of Absolute Configuration of Flexible and Transparent Molecules: Aliphatic Diols As a Case Study
electronic circular dichroism (ECD) spectra, which show several (up to five) Cotton effects in the 350−200 nm range due to valence shell π→π* transitions. These features allow simulation of the chiropticalproperties of these compounds at the TDDFT/B3LYP/6-31G* level of theory to obtain, using the known ACs of these compounds, a satisfactory reproduction of the OR values (sign and order of magnitude; quantitatively
A Ru Catalyzed Divergence: Oxidative Cyclization vs Cycloisomerization of Bis-homopropargylic Alcohols
作者:Barry M. Trost、Young Ho Rhee
DOI:10.1021/ja011840w
日期:2002.3.1
electrophilically initiated direct attack of the hydroxyl group on a pi-complex of the alkyne and ruthenium. A catalytic system composed of CpRu[(p-CH(3)O(6)H(4))(3)P](2)Cl and excess (p-CH(3)O-C(6)H(4))(3)P directs the reaction toward the oxidative cyclization to form delta-lactones in good yields. Significantly, a simple switch of catalyst to CpRu[(p-FC(6)H(4))(3)P](2)Cl redirects the reaction to a cycloisomerization