Fluorine-Containing Organozinc Reagents. Part III. A new formylation reaction of fluroalkylzinc halides

✍ Scribed by Robert Werner Lang

• Publisher: John Wiley and Sons
• Year: 1988
• Tongue: German
• Weight: 221 KB
• Volume: 71
• Category: Article
• ISSN: 0018-019X
• DOI: 10.1002/hlca.19880710210

✦ Synopsis

A new Si-induced Vilsmeier-type formylation of F-containing organozinc reagents is described. This two-step process via the isolable intermediate 10 Seems to be quite general for the synthesis of anhydrous polyhalogenated aldehydes.

Various polyfluorinated hydrocarbons are excellent starting materials for the preparation of versatile F-containing synthetic building blocks [2]. In particular, a simple synthesis of CF,CCl,-substituted alcohols [3] [4] prompted us to further elucidate the Zn-induced addition of 1,1,l-trichloro-2,2,2-trifluoroethane (CF,CCl,, 1) to electrophilic C-centers. After isolation and characterization of the key intermediate 2 [l] and its successful addition to both aldehydes [5] and CO, [6], we were finally looking for an appropriate formylation reaction to generate directly the still missing oxidation state of the aldehyde 4 (Scheme 1). Scheme 1 CF3CCI, 1 I CF,CCI,ZnCI(DMF), 2 CF,CCI,CH,OH CF,C CI,COOH ') Part 11: 111. ' )