title: The lithiation and acyl transfer reactions of phosphine oxides, sulfides and boranes in the synthesis of cyclopropanes.
abstract: Phosphine oxides are lithiated much faster than phosphine sulfides and phosphine boranes. Phosphine sulfides are in turn lithiated much more readily than phosphine boranes. It was possible to trap a phosphine sulfide THF in one case which upon treatment with t-BuOK gave cyclopropane, showing that phosphine sulfides readily undergo both phosphinoyl transfer and cyclopropane ring closure just like their phosphine oxide counterparts. The obtained data show that phosphine oxides are easily lithiated and undergo phosphoryl transfer much more readily and faster than phosphine sulfides and phosphine boranes. The observations suggest that it would be possible to perform reactions involving phosphine oxides in the presence of phosphine boranes or phosphine sulfides, potentially allowing regioselective alkylation of phosphine oxides in the presence of phosphine boranes or phosphine sulfides.
authors.affiliation: Cambridge University, University Chemical Laboratory, Lensfield Road, Cambridge, CB2 1EW, UK.
authors.forename: Celia
authors.initials: C
authors.lastname: Clarke
authors.forename: David J
authors.initials: DJ
authors.lastname: Fox
authors.forename: Daniel Sejer
authors.initials: DS
authors.lastname: Pedersen
authors.forename: Stuart
authors.initials: S
authors.lastname: Warren
mesh_terms: D001880:Boranes / Q000737:chemistry*; D003198:Computer Simulation; D018360:Crystallography, X-Ray; D003521:Cyclopropanes / Q000138:chemical synthesis* / Q000737:chemistry; D008094:Lithium / Q000737:chemistry*; D008956:Models, Chemical; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry; D010087:Oxides / Q000737:chemistry*; D010720:Phosphines / Q000737:chemistry*; D013237:Stereoisomerism; D013440:Sulfides / Q000737:chemistry*
chemical_list: D001880:Boranes; D003521:Cyclopropanes; D009942:Organometallic Compounds; D010087:Oxides; D010720:Phosphines; D013440:Sulfides; D008094:Lithium