METHOD OF SYNTHESIS OF FLUOROALCOHOL (VARIANTS) Russian patent published in 2001 - IPC

FIELD: organic chemical, chemical technology. SUBSTANCE: invention relates to synthesis of fluoroalcohol of the formula (I): H(CFR¹CF₂)_nCH₂OH where R¹ means F or CF₃ when n = 1; R¹ means F when n = 2. Process can be carried out in two variants. The first variant involves reaction of methanol with tetrafluoroethylene or hexafluoropropylene in the presence of free radical producing agent. Process involves feeding the reaction mixture into distillation column, methanol driving off from upper part of distillation column and removal of lower fraction containing fluoroalcohols from distillation column bottom. Then method involves removal of by-side fraction containing water and HF from distillation column, methanol back feeding from upper part of distillation column for recycle and treatment of bottom fraction for extraction of fluoroalcohol presented as formula (I). The second variant is similar to the first one but process is carried out by reaction of methanol with tetrafluoroethylene and hexafluoropropylene and separation of reaction mixture is carried out in two distillation columns. The bottom fraction from the first fractionating column has water, HF and fluoroalcohol presented by formula (I). Upper fraction from the second distillation column has water and HF and bottom fraction has fluoroalcohol presented by formula (I). Methanol from upper part of the first distillation column is fed back to reactor for recycle. EFFECT: improved method of synthesis, enhanced extraction of methanol. 2 cl, 3 dwg, 2 ex