Di(1H,1H,2H,2H-perfluorooctyl)-dibenzo-18-crown-6: A 'light fluorous' recyclable phase transfer catalyst

摘要

A series of dibenzo-18-crown-6 lariat ethers containing two C7H_(15) (11), (CH2)2C6F_(13) (14), (CH2)2C8F_(17) (15), NHC7H_(15) (18) and NHCH2C6F_(13)(19) sidearms were prepared and the single crystal X-ray structure of cis-4,4'-di(1H,1H,2H,2H-perfluorodecyl)-dibenzo-18-crown-6 (15a) is reported. The "light fluorous" dibenzo-18-crown-6 ether (14) has emerged as a stable and robust PTC catalyst, which can be recycled efficiently by fluorous solid-phase extraction, and gives better PTC catalytic activity compared to the parent, non-fluorinated PTC catalyst, dibenzo-18-crown-6, and the alkylated derivative (11) in aliphatic and aromatic nucleophilic substitutions.