Synthesis and properties of 2-trifluoromethyl-substituted 4-pentenoic and 3,4-pentadienoic acids and their esters
摘要:
The hydrolysis of the acid fluorides of 2-fluorocarbonyl(methoxycarbonyl)-2-trifluoromethyl-4-pentenoic acids (I) and (II), and of 2-fluorocarbonyl-(methoxycarbonyl)-2-trifluoromethyl-3,4-pentadienoic acids (III) and (IV) gave, under mild conditions, 2-trifluoromethyl-4-pentenoic acid (V) and 2-trifluoromethyl-3,4-pentadienoic acid (VII) or their methyl esters (VI) and (VIII). The reactivity of these compounds was studied.
Deprotonation of unsaturated fluoroethers, CH2=CHCH2OCF2CHXCF3 and CH?CCH2OCF2CHXCF3 (X=COF and SO2F)
摘要:
2-Fluorocarbonyl- and 2-fluorosulfonylpentafluoropropenes upon cooling add allyl and propargyl alcohols at the C = C bond to form strong CH-Acids (I) - (IV). These CH-acids react with BF3.NEt3 under mild conditions and are converted to 2-fluorocarbonyl- and 2-fluorosulfonyl-2-trifluoromethyl-substituted unsaturated acid fluorides (V) - (VIII). The conditions, rate, and high selectivity of these reactions support the hypothesis that the formation of acid fluorides (V) - (VIII) involves a [3,3]-sigmatropic rearrangement of intermediate carbanions (Ia) - (IVa).