Synthesis of Allenyl Esters by Horner–Wadsworth–Emmons Reactions of Ketenes Mediated by Isopropylmagnesium Bromide

Abstract

The synthesis of conjugated allenyl esters (tri-substituted allenes) was achieved by magnesium(II)-mediated Horner–Wadsworth–Emmons reaction of methyl bis(2,2,2-trifluoroethyl)phosphonoacetate with disubstituted ketenes. In addition, a novel access to α-fluorinated allenyl carboxamides (tetrasubstituted allenes) is presented.

Key words

Horner–Wadsworth–Emmons reaction - allenes - ketenes - Grignard reagents - fluorine

• References

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