We have established the Rh-catalyzed high-yielding and highly 1,3,5-selective [2+2+2] cycloaddition of push-pull internal alkynes. This reaction allows for the shape- and size-tunable synthesis of covalent organic cages (aryl ether cages) using push-pull internal diynes. Some aryl ether cages encapsulated isolated water molecules in their hydrophobic cavity by hydrogen bonding with the multiple ester
An efficient method for the synthesis of (E)-1,2-dichloro- 1-phenoxyethenes 2 has been developed. The reaction of phenol derivatives 1 with trichloroethylene at ambient temperature by means of Cs2CO3-DMSO system furnished the corresponding aryl vinyl ethers 2 in excellent yields. On the other hand, the same reaction of phenol derivatives li, 1k and 1p possessing an electron-withdrawing group at the o- or p-position of the hydroxy group required a harsh reaction conditions to heat at 70 degrees C for the synthesis of the desired products 2i, 2k and 2p.
Highly asymmetric synthesis of (+)-corsifuran A. Elucidation of the electronic requirements in the Ruthenium–NHC catalyzed hydrogenation of benzofurans
synthesis of ent-corsifuran A by a highlyasymmetrichydrogenation of a benzofuran precursor is reported. In addition, the electronic influence of the substituents on the asymmetrichydrogenation of benzofurans is provided. Whereas the hydrogenation of electron-deficient benzofurans was achieved under very mild conditions, the presence of electron-donating groups in the benzofuran required harsher reaction