METHOD FOR THE PREPARATION OF ALPHA,ALPHA,ALPHA',ALPHA'-TETRAFLUORO-P-XYLENE
申请人:Jong Jeng Shean
公开号:US20050283031A1
公开(公告)日:2005-12-22
A method for the preparation of α,α,α′,α′-tetrafluoro-p-xylene is disclosed. α,α,α′,α′-tetrachloro-p-xylene and KF and a small amount of phase transfer catalyst are dissolved in solvent, xylene, and undergo a recycle reaction for 48 hours, after which 60% of the product is obtained.
A method for the synthesis of TFPX (α,α,α′,α′-tetrafluoro-p-xylene) is disclosed, which comprises the following steps: (a) providing a sulpholane solution comprising TCPX (α,α,α′,α′-tetrachloro-p-xylene); (b) mixing the sulpholane solution with alkali metal fluoride, and phase transfer catalyst to form a mixture, wherein the phase transfer catalyst is quaternary phosphonium salt; and (c) heating the mixture.
A method for transferring TCPX (α, α, α′, α′-tetrachloro-p-xylene) into TFPX (α, α, α′, α′-tetrafluoro-p-xylene) is disclosed, which comprises the following steps: (a) providing a first reactant comprising TFPX; (b) mixing the first reactant with alkali metal fluorides, TCPX and phase transfer catalyst(s) to form a mixture, wherein the alkali metal fluorides is KF, CsF, NaF, LiF or the combination thereof, the phase transfer catalyst(s) is quaternary ammonium salt, quaternary phosphonium salt or the combination thereof; and (c) heating the mixture.