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Reactions of a Lewis acidic methylene phosphonium cationic adduct with olefins
Linkun Miao1, Amir Yeganeh-Salman1, Jason Yeung1
1Department of Chemistry, University of Toronto, 80 St George St, Toronto, Ontario, Canada M5S3H6. douglas.stephan@utoronto.ca.
Abstract:
Efforts to deprotonate the halophosphonium cations [Ph2P(X)Me]+ (X = F, Cl) generated species of the form [Ph2(X)PC(H)PPh2Me][X']. The derivative where X = O3SCF3 provides access to a methylene phosphonium cation. The coordinated triflate anion can be replaced by Et3PO and dimethylaminopyridine (DMAP). In addition, the cation reacts with the olefins R2CCH2 (R = Ph, Me) and PhMeCCH2. While Ph2CCH2 was shown to give the species [Ph2(Ph2CCH)PCH2PPh2Me][O3SCF3]2 with a pendant vinyl group, reactions with methyl substituted olefins undergo additional isomerization to form [Ph2(RCH2CCH2)PCH2PPh2Me][O3SCF3]2 (R = Ph, Me) featuring pendant allyl moieties.
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