Inverse Wittig-type reactions

Application of the microwave technique offered advantages in organo-phosphorus chemistry, such as in the Kabachnik-Fields reaction, in Diels-Alder cycloaddition and in an inverse Wittig-type reaction to synthesize phosphine oxide derivatives. ... 

The novel inverse Wittig type reaction of cyclic phosphine oxides and dialkyl acetylenedicarboxylates, yielding P-oxophosphoranes, was accomplished under microwave conditions (Scheme 42). Hence, the reaction time was only ca. 3 h (instead of 2 weeks) at 150 °C and the yields were higher. ... 

Diels-Alder Cycloadditions, Fragmentation-Related Phosphorylations, and Inverse Wittig-Type Reactions 563... 

DIELS-ALDER CYCLOADDITIONS, FE GMENTATION-RELATED PHOSPHORYLATIONS, AND INVERSE WITTIG-TYPE REACTIONS... 

SCHEME 10 Inverse Wittig-type reaction instead of Diels-Alder cydoaddition. 

Two different strategies for the incorporation of the thiazole moiety were used so far either Stille coupling reactions of 4-stannylthiazoles by one group [18, 19] or Wittig-type ole-fination reactions by all others. The latter approach requires either 2-methyl-thiazole-4-carbaldehyde (4, Scheme 1) available from the corresponding ester by reduction [13, 20, 29, 30] or suitable 4-phosphorusmethyl derivatives (3a-d. Schemes 1 and 4) for the more common inverse approach. 

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