Reactivity induced by the phosphonio group

Initial electrode electron transfer Competitive radical cleavage Dimerization 

H-atom transfer disproportionation Second wave electrode electron transfer Second wave solution electron transfer Hofmann degradation Ylide formation Phosphine oxide formation 

SCHEME 10. Reduction mechanism of 1,2-vinylene and buta-l,4-dienylene bisphosphonium salts (counterion omitted)182. 

Alkoxy(trisdimethylamino)phosphonium salts (PF6, C104 or BF4 as anions)765 are also used for the same purpose with good yields of course, alkoxy groups can be chosen as optically active451,766,767. Moreover, when the alkoxy chain is functionalized in the appropriate position by oxyanions, intramolecular etherification is made possible 3,6-anhydrohexosides were prepared in this way537 (reaction 232). 

Nu = alkyl—OH, alkyl—COOH, alkyl—COO-, aryl-COOH, aryl—SH, alkyl-NH2, dialkyl—NH, halides R = primary or secondary alkyl 

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