A preparation of trifluorolactic aldehyde

A five-step preparation of 2-benzoyloxy-3,3,3-trifluoropropanal from 1,2-ep oxy-3,3,3-trifluoropropane via Pummerer rearrangement is described. The tot al yield of the aldehyde from the epoxide was 90%. The aldehyde kept its op tical purity when it was in hydrate form, but it was found to readily racem ize in its formyl form. The utilization of selenium instead of sulfur in th ese procedures offered advantages in controlled oxidation of the heteroatom for Pummerer rearrangement and the subsequent hydrolysis of Pummerer produ ct, an aldehyde equivalent. (C) 1999 Elsevier Science Ltd. All rights reser ved.