Iodomethylzinc phosphates: powerful reagents for the cyclopropanation of alkenes.
A new family of zinc carbenoids derived from phosphoric acids was developed and used in the cyclopropanation of allylic alcohols and ethers and also of unfunctionalized olefins. The use of the chiral phosphoric acid of a 3,3'-disubstituted BINOL leads to efficient stereocontrol, affording the cyclopropanes of allylic and homoallylic ethers with complete conversions and up to 93% ee. A catalytic version of this reaction using 10 mol % of the chiral phosphate reagent is also disclosed.
Lacasse
Marie-Christine
MC
Département de Chimie, Université de Montréal, P.O. Box 6128, Station Downtown, Montréal, Québec, Canada H3C 3J7.
Poulard
Cyril
C
Charette
André B
AB
D000475:Alkenes / Q000138:chemical synthesis*; D018360:Crystallography, X-Ray; D003500:Cyclization; D006847:Hydrocarbons, Iodinated / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D010710:Phosphates / Q000737:chemistry*; D015032:Zinc / Q000737:chemistry*
D000475:Alkenes; D006847:Hydrocarbons, Iodinated; D009942:Organometallic Compounds; D010710:Phosphates; C027946:methylene iodide; D015032:Zinc